Code:
/ Net / Net / 3.5.50727.3053 / DEVDIV / depot / DevDiv / releases / whidbey / netfxsp / ndp / fx / src / Data / System / Data / DataColumnCollection.cs / 6 / DataColumnCollection.cs
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// [....]
// [....]
// [....]
//-----------------------------------------------------------------------------
namespace System.Data {
using System;
using System.Xml;
using System.Collections;
using System.ComponentModel;
using System.Data.Common;
using System.Diagnostics;
///
/// Represents a collection of
///
[
DefaultEvent("CollectionChanged"),
Editor("Microsoft.VSDesigner.Data.Design.ColumnsCollectionEditor, " + AssemblyRef.MicrosoftVSDesigner, "System.Drawing.Design.UITypeEditor, " + AssemblyRef.SystemDrawing),
]
#if WINFSInternalOnly
internal
#else
public
#endif
sealed class DataColumnCollection : InternalDataCollectionBase {
private readonly DataTable table;
private readonly ArrayList _list = new ArrayList();
private int defaultNameIndex = 1;
private DataColumn[] delayedAddRangeColumns;
private readonly Hashtable columnFromName; // this hashtable contains name of colunms in this collection and name of Nested Child DataTAble
private CollectionChangeEventHandler onCollectionChangedDelegate;
private CollectionChangeEventHandler onCollectionChangingDelegate;
private CollectionChangeEventHandler onColumnPropertyChangedDelegate;
private bool fInClear;
private DataColumn[] columnsImplementingIChangeTracking = DataTable.zeroColumns;
private int nColumnsImplementingIChangeTracking = 0;
private int nColumnsImplementingIRevertibleChangeTracking = 0;
///
/// DataColumnCollection constructor. Used only by DataTable.
///
internal DataColumnCollection(DataTable table) {
this.table = table;
columnFromName = new Hashtable();
}
///
/// Gets the list of the collection items.
///
protected override ArrayList List {
get {
return _list;
}
}
internal DataColumn[] ColumnsImplementingIChangeTracking {
get {
return columnsImplementingIChangeTracking;
}
}
internal int ColumnsImplementingIChangeTrackingCount{
get {
return nColumnsImplementingIChangeTracking;
}
}
internal int ColumnsImplementingIRevertibleChangeTrackingCount {
get {
return nColumnsImplementingIRevertibleChangeTracking;
}
}
///
///
/// Gets the
///
public DataColumn this[int index] {
get {
try { // Perf: use the readonly _list field directly and let ArrayList check the range
return (DataColumn)_list[index];
}
catch(ArgumentOutOfRangeException) {
throw ExceptionBuilder.ColumnOutOfRange(index);
}
}
}
///
/// Gets the
///
public DataColumn this[string name] {
get {
if (null == name) {
throw ExceptionBuilder.ArgumentNull("name");
}
DataColumn column = columnFromName[name] as DataColumn;
if (null == column) {
// Case-Insensitive compares
int index = IndexOfCaseInsensitive(name);
if (0 <= index) {
column = (DataColumn)_list[index];
}
else if (-2 == index) {
throw ExceptionBuilder.CaseInsensitiveNameConflict(name);
}
}
return column;
}
}
internal DataColumn this[string name, string ns]
{
get
{
DataColumn column = columnFromName[name] as DataColumn;
if (column != null && column.Namespace == ns)
return column;
return null;
}
}
///
/// Adds the specified
///
public void Add(DataColumn column) {
AddAt(-1, column);
}
internal void AddAt(int index, DataColumn column) {
if (column != null && column.ColumnMapping == MappingType.SimpleContent) {
if (table.XmlText != null && table.XmlText != column)
throw ExceptionBuilder.CannotAddColumn3();
if (table.ElementColumnCount > 0)
throw ExceptionBuilder.CannotAddColumn4(column.ColumnName);
OnCollectionChanging(new CollectionChangeEventArgs(CollectionChangeAction.Add, column));
BaseAdd(column);
if (index != -1)
ArrayAdd(index, column);
else
ArrayAdd(column);
table.XmlText = column;
}
else {
OnCollectionChanging(new CollectionChangeEventArgs(CollectionChangeAction.Add, column));
BaseAdd(column);
if (index != -1)
ArrayAdd(index, column);
else
ArrayAdd(column);
// if the column is an element increase the internal dataTable counter
if (column.ColumnMapping == MappingType.Element)
table.ElementColumnCount ++;
}
if (!table.fInitInProgress && column != null && column.Computed) {
column.Expression = column.Expression;
}
OnCollectionChanged(new CollectionChangeEventArgs(CollectionChangeAction.Add, column));
}
///
/// [To be supplied.]
///
public void AddRange(DataColumn[] columns) {
if (table.fInitInProgress) {
delayedAddRangeColumns = columns;
return;
}
if (columns != null) {
foreach(DataColumn column in columns) {
if (column != null) {
Add(column);
}
}
}
}
///
/// Creates and adds a
///
public DataColumn Add(string columnName, Type type, string expression) {
DataColumn column = new DataColumn(columnName, type, expression);
Add(column);
return column;
}
///
/// Creates and adds a
///
public DataColumn Add(string columnName, Type type) {
DataColumn column = new DataColumn(columnName, type);
Add(column);
return column;
}
///
/// Creates and adds a
///
public DataColumn Add(string columnName) {
DataColumn column = new DataColumn(columnName);
Add(column);
return column;
}
///
/// Creates and adds a
///
public DataColumn Add() {
DataColumn column = new DataColumn();
Add(column);
return column;
}
///
/// Occurs when the columns collection changes, either by adding or removing a column.
///
[ResDescriptionAttribute(Res.collectionChangedEventDescr)]
public event CollectionChangeEventHandler CollectionChanged {
add {
onCollectionChangedDelegate += value;
}
remove {
onCollectionChangedDelegate -= value;
}
}
internal event CollectionChangeEventHandler CollectionChanging {
add {
onCollectionChangingDelegate += value;
}
remove {
onCollectionChangingDelegate -= value;
}
}
internal event CollectionChangeEventHandler ColumnPropertyChanged {
add {
onColumnPropertyChangedDelegate += value;
}
remove {
onColumnPropertyChangedDelegate -= value;
}
}
///
/// Adds the column to the columns array.
///
private void ArrayAdd(DataColumn column) {
_list.Add(column);
column.SetOrdinalInternal(_list.Count - 1);
CheckIChangeTracking(column);
}
private void ArrayAdd(int index, DataColumn column) {
_list.Insert(index, column);
CheckIChangeTracking(column);
}
private void ArrayRemove(DataColumn column) {
column.SetOrdinalInternal(-1);
_list.Remove(column);
int count = _list.Count;
for (int i =0; i < count; i++) {
((DataColumn) _list[i]).SetOrdinalInternal(i);
}
if (column.ImplementsIChangeTracking) {
RemoveColumnsImplementingIChangeTrackingList(column);
}
}
///
/// Creates a new default name.
///
internal string AssignName() {
string newName = MakeName(defaultNameIndex++);
while (columnFromName[newName] != null)
newName = MakeName(defaultNameIndex++);
return newName;
}
///
/// Does verification on the column and it's name, and points the column at the dataSet that owns this collection.
/// An ArgumentNullException is thrown if this column is null. An ArgumentException is thrown if this column
/// already belongs to this collection, belongs to another collection.
/// A DuplicateNameException is thrown if this collection already has a column with the same
/// name (case insensitive).
///
private void BaseAdd(DataColumn column) {
if (column == null)
throw ExceptionBuilder.ArgumentNull("column");
if (column.table == table)
throw ExceptionBuilder.CannotAddColumn1(column.ColumnName);
if (column.table != null)
throw ExceptionBuilder.CannotAddColumn2(column.ColumnName);
if (column.ColumnName.Length == 0) {
column.ColumnName = AssignName();
}
RegisterColumnName(column.ColumnName, column, (DataTable)null);
try {
column.SetTable(table);
if (!table.fInitInProgress && column.Computed) {
if (column.DataExpression.DependsOn(column)) {
throw ExceptionBuilder.ExpressionCircular();
}
}
if (0 < table.RecordCapacity) {
// adding a column to table with existing rows
column.SetCapacity(table.RecordCapacity);
}
// fill column with default value.
for (int record = 0; record < table.RecordCapacity; record++) {
column.InitializeRecord(record);
}
if (table.DataSet != null) {
column.OnSetDataSet();
}
}
catch (Exception e) {
//
if (ADP.IsCatchableOrSecurityExceptionType(e)) {
UnregisterName(column.ColumnName);
}
throw;
}
}
///
/// BaseGroupSwitch will intelligently remove and add tables from the collection.
///
private void BaseGroupSwitch(DataColumn[] oldArray, int oldLength, DataColumn[] newArray, int newLength) {
// We're doing a smart diff of oldArray and newArray to find out what
// should be removed. We'll pass through oldArray and see if it exists
// in newArray, and if not, do remove work. newBase is an opt. in case
// the arrays have similar prefixes.
int newBase = 0;
for (int oldCur = 0; oldCur < oldLength; oldCur++) {
bool found = false;
for (int newCur = newBase; newCur < newLength; newCur++) {
if (oldArray[oldCur] == newArray[newCur]) {
if (newBase == newCur) {
newBase++;
}
found = true;
break;
}
}
if (!found) {
// This means it's in oldArray and not newArray. Remove it.
if (oldArray[oldCur].Table == table) {
BaseRemove(oldArray[oldCur]);
_list.Remove(oldArray[oldCur]);
oldArray[oldCur].SetOrdinalInternal(-1);
}
}
}
// Now, let's pass through news and those that don't belong, add them.
for (int newCur = 0; newCur < newLength; newCur++) {
if (newArray[newCur].Table != table) {
BaseAdd(newArray[newCur]);
_list.Add(newArray[newCur]);
}
newArray[newCur].SetOrdinalInternal(newCur);
}
}
///
/// Does verification on the column and it's name, and clears the column's dataSet pointer.
/// An ArgumentNullException is thrown if this column is null. An ArgumentException is thrown
/// if this column doesn't belong to this collection or if this column is part of a relationship.
/// An ArgumentException is thrown if another column's compute expression depends on this column.
///
private void BaseRemove(DataColumn column) {
if (CanRemove(column, true)) {
// remove
if (column.errors > 0) {
for (int i = 0; i < table.Rows.Count; i++) {
table.Rows[i].ClearError(column);
}
}
UnregisterName(column.ColumnName);
column.SetTable(null);
}
}
///
/// Checks
/// if
/// a given column can be removed from the collection.
///
public bool CanRemove(DataColumn column) {
return CanRemove(column, false);
}
internal bool CanRemove(DataColumn column, bool fThrowException) {
if (column == null) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.ArgumentNull("column");
}
if (column.table != table) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveColumn();
}
// allow subclasses to complain first.
table.OnRemoveColumnInternal(column);
// We need to make sure the column is not involved in any Relations or Constriants
if (table.primaryKey != null && table.primaryKey.Key.ContainsColumn(column)) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemovePrimaryKey();
}
for (int i = 0; i < table.ParentRelations.Count; i++) {
if (table.ParentRelations[i].ChildKey.ContainsColumn(column)) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveChildKey(table.ParentRelations[i].RelationName);
}
}
for (int i = 0; i < table.ChildRelations.Count; i++) {
if (table.ChildRelations[i].ParentKey.ContainsColumn(column)) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveChildKey(table.ChildRelations[i].RelationName);
}
}
for (int i = 0; i < table.Constraints.Count; i++) {
if (table.Constraints[i].ContainsColumn(column))
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveConstraint(table.Constraints[i].ConstraintName, table.Constraints[i].Table.TableName);
}
if (table.DataSet != null) {
for (ParentForeignKeyConstraintEnumerator en = new ParentForeignKeyConstraintEnumerator(table.DataSet, table); en.GetNext();) {
Constraint constraint = en.GetConstraint();
if (((ForeignKeyConstraint)constraint).ParentKey.ContainsColumn(column))
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveConstraint(constraint.ConstraintName, constraint.Table.TableName);
}
}
if (column.dependentColumns != null) {
for (int i = 0; i < column.dependentColumns.Count; i++) {
DataColumn col = column.dependentColumns[i];
if (fInClear && (col.Table == table || col.Table == null))
continue;
if (col.Table == null)
continue;
Debug.Assert(col.Computed, "invalid (non an expression) column in the expression dependent columns");
DataExpression expr = col.DataExpression;
if ((expr!= null) && (expr.DependsOn(column))) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveExpression(col.ColumnName, col.Expression);
}
}
}
// SQLBU 429176: you can't remove a column participating in an index,
// while index events are suspended else the indexes won't be properly maintained.
// However, all the above checks should catch those participating columns.
// except when a column is in a DataView RowFilter or Sort clause
foreach (Index index in table.LiveIndexes) {
#if false
if (!Object.ReferenceEquals(index, column.sortIndex)) {
foreach (IndexField field in index.IndexFields) {
if (Object.ReferenceEquals(field.Column, column)) {
if (fThrowException) {
throw ExceptionBuilder.CannotRemoveExpression("DataView", column.ColumnName);
}
return false;
}
}
}
#endif
}
return true;
}
private void CheckIChangeTracking(DataColumn column) {
if (column.ImplementsIRevertibleChangeTracking) {
nColumnsImplementingIRevertibleChangeTracking++;
nColumnsImplementingIChangeTracking++;
AddColumnsImplementingIChangeTrackingList(column);
}
else if (column.ImplementsIChangeTracking) {
nColumnsImplementingIChangeTracking++;
AddColumnsImplementingIChangeTrackingList(column);
}
}
///
///
/// Clears the collection of any columns.
///
///
public void Clear() {
int oldLength = _list.Count;
DataColumn[] columns = new DataColumn[_list.Count];
_list.CopyTo(columns, 0);
OnCollectionChanging(RefreshEventArgs);
if (table.fInitInProgress && delayedAddRangeColumns != null) {
delayedAddRangeColumns = null;
}
try {
// this will smartly add and remove the appropriate tables.
fInClear = true;
BaseGroupSwitch(columns, oldLength, null, 0);
fInClear = false;
}
catch (Exception e) {
//
if (ADP.IsCatchableOrSecurityExceptionType(e)) {
// something messed up: restore to old values and throw
fInClear = false;
BaseGroupSwitch(null, 0, columns, oldLength);
_list.Clear();
for (int i = 0; i < oldLength; i++)
_list.Add(columns[i]);
}
throw;
}
_list.Clear();
table.ElementColumnCount = 0;
OnCollectionChanged(RefreshEventArgs);
}
///
/// Checks whether the collection contains a column with the specified name.
///
public bool Contains(string name) {
DataColumn column = columnFromName[name] as DataColumn;
if (column != null) {
return true;
}
return (IndexOfCaseInsensitive(name) >= 0);
}
internal bool Contains(string name, bool caseSensitive) {
DataColumn column = columnFromName[name] as DataColumn;
if (column != null) {
return true;
}
if (caseSensitive) { // above check did case sensitive check
return false;
}
else {
return (IndexOfCaseInsensitive(name) >= 0);
}
}
public void CopyTo(DataColumn[] array, int index) {
if (array==null)
throw ExceptionBuilder.ArgumentNull("array");
if (index < 0)
throw ExceptionBuilder.ArgumentOutOfRange("index");
if (array.Length - index < _list.Count)
throw ExceptionBuilder.InvalidOffsetLength();
for(int i = 0; i < _list.Count; ++i) {
array[index + i] = (DataColumn)_list[i];
}
}
///
///
/// Returns the index of a specified
///
public int IndexOf(DataColumn column) {
int columnCount = _list.Count;
for (int i = 0; i < columnCount; ++i) {
if (column == (DataColumn) _list[i]) {
return i;
}
}
return -1;
}
///
/// Returns the index of
/// a column specified by name.
///
public int IndexOf(string columnName) {
if ((null != columnName) && (0 < columnName.Length)) {
int count = Count;
DataColumn column = columnFromName[columnName] as DataColumn;
if (column != null) {
for (int j = 0; j < count; j++)
if (column == _list[j]) {
return j;
}
}
else {
int res = IndexOfCaseInsensitive(columnName);
return (res < 0) ? -1 : res;
}
}
return -1;
}
internal int IndexOfCaseInsensitive (string name) {
int hashcode = table.GetSpecialHashCode(name);
int cachedI = -1;
DataColumn column = null;
for (int i = 0; i < Count; i++) {
column = (DataColumn) _list[i];
if ( (hashcode == 0 || column._hashCode == 0 || column._hashCode == hashcode) &&
NamesEqual(column.ColumnName, name, false, table.Locale) != 0 ) {
if (cachedI == -1)
cachedI = i;
else
return -2;
}
}
return cachedI;
}
internal void FinishInitCollection() {
if (delayedAddRangeColumns != null) {
foreach(DataColumn column in delayedAddRangeColumns) {
if (column != null) {
Add(column);
}
}
foreach(DataColumn column in delayedAddRangeColumns) {
if (column != null) {
column.FinishInitInProgress();
}
}
delayedAddRangeColumns = null;
}
}
///
/// Makes a default name with the given index. e.g. Column1, Column2, ... Columni
///
private string MakeName(int index) {
if (1 == index) {
return "Column1";
}
return "Column" + index.ToString(System.Globalization.CultureInfo.InvariantCulture);
}
internal void MoveTo(DataColumn column, int newPosition) {
if (0 > newPosition || newPosition > Count -1) {
throw ExceptionBuilder.InvalidOrdinal("ordinal", newPosition);
}
if (column.ImplementsIChangeTracking) {
RemoveColumnsImplementingIChangeTrackingList(column);
}
_list.Remove(column);
_list.Insert(newPosition, column);
int count = _list.Count;
for (int i =0; i < count; i++) {
((DataColumn) _list[i]).SetOrdinalInternal(i);
}
CheckIChangeTracking(column);
OnCollectionChanged(new CollectionChangeEventArgs(CollectionChangeAction.Refresh, column));
}
///
///
/// Raises the
///
private void OnCollectionChanged(CollectionChangeEventArgs ccevent) {
table.UpdatePropertyDescriptorCollectionCache();
if ((null != ccevent) && !table.SchemaLoading && !table.fInitInProgress) {
DataColumn column = (DataColumn)ccevent.Element;
}
if (onCollectionChangedDelegate != null) {
onCollectionChangedDelegate(this, ccevent);
}
}
///
/// [To be supplied.]
///
private void OnCollectionChanging(CollectionChangeEventArgs ccevent) {
if (onCollectionChangingDelegate != null) {
onCollectionChangingDelegate(this, ccevent);
}
}
internal void OnColumnPropertyChanged(CollectionChangeEventArgs ccevent) {
table.UpdatePropertyDescriptorCollectionCache();
if (onColumnPropertyChangedDelegate != null) {
onColumnPropertyChangedDelegate(this, ccevent);
}
}
///
/// Registers this name as being used in the collection. Will throw an ArgumentException
/// if the name is already being used. Called by Add, All property, and Column.ColumnName property.
/// if the name is equivalent to the next default name to hand out, we increment our defaultNameIndex.
///
internal void RegisterColumnName(string name, DataColumn column, DataTable table) {
Debug.Assert (name != null);
Debug.Assert ((null == column) != (null == table), "RegisterColumnName wrong usage");
Object _exObject = columnFromName[name];
if (_exObject != null) {
if (_exObject is DataColumn) {
if (null != column) {
throw ExceptionBuilder.CannotAddDuplicate(name);
}
else {
throw ExceptionBuilder.CannotAddDuplicate3(name);
}
}
throw ExceptionBuilder.CannotAddDuplicate2(name);
}
//we need to check wether the tableName is the same of the
//next generable columnName and update defaultNameIndex accordingly
if ((null != table) && NamesEqual(name, MakeName(defaultNameIndex), true, this.table.Locale) != 0) {
do {
defaultNameIndex++;
} while (Contains(MakeName(defaultNameIndex)));
}
if (null != column) {
column._hashCode = this.table.GetSpecialHashCode(name);
columnFromName.Add(name, column);
}
else {
columnFromName.Add(name, table);
}
}
internal bool CanRegisterName(string name) {
Debug.Assert (name != null);
return (null == columnFromName[name]);
}
///
/// Removes the specified
///
public void Remove(DataColumn column) {
OnCollectionChanging(new CollectionChangeEventArgs(CollectionChangeAction.Remove, column));
BaseRemove(column);
ArrayRemove(column);
OnCollectionChanged(new CollectionChangeEventArgs(CollectionChangeAction.Remove, column));
// if the column is an element decrease the internal dataTable counter
if (column.ColumnMapping == MappingType.Element)
table.ElementColumnCount --;
}
///
/// Removes the
/// column at the specified index from the collection.
///
public void RemoveAt(int index) {
DataColumn dc = this[index];
if (dc == null)
throw ExceptionBuilder.ColumnOutOfRange(index);
Remove(dc);
}
///
/// Removes the
/// column with the specified name from the collection.
///
public void Remove(string name) {
DataColumn dc = this[name];
if (dc == null)
throw ExceptionBuilder.ColumnNotInTheTable(name, table.TableName);
Remove(dc);
}
///
/// Unregisters this name as no longer being used in the collection. Called by Remove, All property, and
/// Column.ColumnName property. If the name is equivalent to the last proposed default namem, we walk backwards
/// to find the next proper default name to hang out.
///
internal void UnregisterName(string name) {
Object obj = columnFromName[name];
if (obj != null) // sinc the HashTable is case-sensitive
columnFromName.Remove(name); // this is totally equivalent
if (NamesEqual(name, MakeName(defaultNameIndex - 1), true, table.Locale) != 0) {
do {
defaultNameIndex--;
} while (defaultNameIndex > 1 &&
!Contains(MakeName(defaultNameIndex - 1)));
}
}
private void AddColumnsImplementingIChangeTrackingList(DataColumn dataColumn) {
DataColumn[] columns = columnsImplementingIChangeTracking;
DataColumn[] tempColumns = new DataColumn[columns.Length +1];
columns.CopyTo(tempColumns, 0);
tempColumns[columns.Length] = dataColumn;
columnsImplementingIChangeTracking = tempColumns;
}
private void RemoveColumnsImplementingIChangeTrackingList(DataColumn dataColumn) {
DataColumn[] columns = columnsImplementingIChangeTracking;
DataColumn[] tempColumns = new DataColumn[columns.Length - 1];
for(int i = 0, j = 0; i < columns.Length; i++) {
if (columns[i] != dataColumn) {
tempColumns[j++] = columns[i];
}
}
columnsImplementingIChangeTracking = tempColumns;
}
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// [....]
// [....]
// [....]
//-----------------------------------------------------------------------------
namespace System.Data {
using System;
using System.Xml;
using System.Collections;
using System.ComponentModel;
using System.Data.Common;
using System.Diagnostics;
///
/// Represents a collection of
///
[
DefaultEvent("CollectionChanged"),
Editor("Microsoft.VSDesigner.Data.Design.ColumnsCollectionEditor, " + AssemblyRef.MicrosoftVSDesigner, "System.Drawing.Design.UITypeEditor, " + AssemblyRef.SystemDrawing),
]
#if WINFSInternalOnly
internal
#else
public
#endif
sealed class DataColumnCollection : InternalDataCollectionBase {
private readonly DataTable table;
private readonly ArrayList _list = new ArrayList();
private int defaultNameIndex = 1;
private DataColumn[] delayedAddRangeColumns;
private readonly Hashtable columnFromName; // this hashtable contains name of colunms in this collection and name of Nested Child DataTAble
private CollectionChangeEventHandler onCollectionChangedDelegate;
private CollectionChangeEventHandler onCollectionChangingDelegate;
private CollectionChangeEventHandler onColumnPropertyChangedDelegate;
private bool fInClear;
private DataColumn[] columnsImplementingIChangeTracking = DataTable.zeroColumns;
private int nColumnsImplementingIChangeTracking = 0;
private int nColumnsImplementingIRevertibleChangeTracking = 0;
///
/// DataColumnCollection constructor. Used only by DataTable.
///
internal DataColumnCollection(DataTable table) {
this.table = table;
columnFromName = new Hashtable();
}
///
/// Gets the list of the collection items.
///
protected override ArrayList List {
get {
return _list;
}
}
internal DataColumn[] ColumnsImplementingIChangeTracking {
get {
return columnsImplementingIChangeTracking;
}
}
internal int ColumnsImplementingIChangeTrackingCount{
get {
return nColumnsImplementingIChangeTracking;
}
}
internal int ColumnsImplementingIRevertibleChangeTrackingCount {
get {
return nColumnsImplementingIRevertibleChangeTracking;
}
}
///
///
/// Gets the
///
public DataColumn this[int index] {
get {
try { // Perf: use the readonly _list field directly and let ArrayList check the range
return (DataColumn)_list[index];
}
catch(ArgumentOutOfRangeException) {
throw ExceptionBuilder.ColumnOutOfRange(index);
}
}
}
///
/// Gets the
///
public DataColumn this[string name] {
get {
if (null == name) {
throw ExceptionBuilder.ArgumentNull("name");
}
DataColumn column = columnFromName[name] as DataColumn;
if (null == column) {
// Case-Insensitive compares
int index = IndexOfCaseInsensitive(name);
if (0 <= index) {
column = (DataColumn)_list[index];
}
else if (-2 == index) {
throw ExceptionBuilder.CaseInsensitiveNameConflict(name);
}
}
return column;
}
}
internal DataColumn this[string name, string ns]
{
get
{
DataColumn column = columnFromName[name] as DataColumn;
if (column != null && column.Namespace == ns)
return column;
return null;
}
}
///
/// Adds the specified
///
public void Add(DataColumn column) {
AddAt(-1, column);
}
internal void AddAt(int index, DataColumn column) {
if (column != null && column.ColumnMapping == MappingType.SimpleContent) {
if (table.XmlText != null && table.XmlText != column)
throw ExceptionBuilder.CannotAddColumn3();
if (table.ElementColumnCount > 0)
throw ExceptionBuilder.CannotAddColumn4(column.ColumnName);
OnCollectionChanging(new CollectionChangeEventArgs(CollectionChangeAction.Add, column));
BaseAdd(column);
if (index != -1)
ArrayAdd(index, column);
else
ArrayAdd(column);
table.XmlText = column;
}
else {
OnCollectionChanging(new CollectionChangeEventArgs(CollectionChangeAction.Add, column));
BaseAdd(column);
if (index != -1)
ArrayAdd(index, column);
else
ArrayAdd(column);
// if the column is an element increase the internal dataTable counter
if (column.ColumnMapping == MappingType.Element)
table.ElementColumnCount ++;
}
if (!table.fInitInProgress && column != null && column.Computed) {
column.Expression = column.Expression;
}
OnCollectionChanged(new CollectionChangeEventArgs(CollectionChangeAction.Add, column));
}
///
/// [To be supplied.]
///
public void AddRange(DataColumn[] columns) {
if (table.fInitInProgress) {
delayedAddRangeColumns = columns;
return;
}
if (columns != null) {
foreach(DataColumn column in columns) {
if (column != null) {
Add(column);
}
}
}
}
///
/// Creates and adds a
///
public DataColumn Add(string columnName, Type type, string expression) {
DataColumn column = new DataColumn(columnName, type, expression);
Add(column);
return column;
}
///
/// Creates and adds a
///
public DataColumn Add(string columnName, Type type) {
DataColumn column = new DataColumn(columnName, type);
Add(column);
return column;
}
///
/// Creates and adds a
///
public DataColumn Add(string columnName) {
DataColumn column = new DataColumn(columnName);
Add(column);
return column;
}
///
/// Creates and adds a
///
public DataColumn Add() {
DataColumn column = new DataColumn();
Add(column);
return column;
}
///
/// Occurs when the columns collection changes, either by adding or removing a column.
///
[ResDescriptionAttribute(Res.collectionChangedEventDescr)]
public event CollectionChangeEventHandler CollectionChanged {
add {
onCollectionChangedDelegate += value;
}
remove {
onCollectionChangedDelegate -= value;
}
}
internal event CollectionChangeEventHandler CollectionChanging {
add {
onCollectionChangingDelegate += value;
}
remove {
onCollectionChangingDelegate -= value;
}
}
internal event CollectionChangeEventHandler ColumnPropertyChanged {
add {
onColumnPropertyChangedDelegate += value;
}
remove {
onColumnPropertyChangedDelegate -= value;
}
}
///
/// Adds the column to the columns array.
///
private void ArrayAdd(DataColumn column) {
_list.Add(column);
column.SetOrdinalInternal(_list.Count - 1);
CheckIChangeTracking(column);
}
private void ArrayAdd(int index, DataColumn column) {
_list.Insert(index, column);
CheckIChangeTracking(column);
}
private void ArrayRemove(DataColumn column) {
column.SetOrdinalInternal(-1);
_list.Remove(column);
int count = _list.Count;
for (int i =0; i < count; i++) {
((DataColumn) _list[i]).SetOrdinalInternal(i);
}
if (column.ImplementsIChangeTracking) {
RemoveColumnsImplementingIChangeTrackingList(column);
}
}
///
/// Creates a new default name.
///
internal string AssignName() {
string newName = MakeName(defaultNameIndex++);
while (columnFromName[newName] != null)
newName = MakeName(defaultNameIndex++);
return newName;
}
///
/// Does verification on the column and it's name, and points the column at the dataSet that owns this collection.
/// An ArgumentNullException is thrown if this column is null. An ArgumentException is thrown if this column
/// already belongs to this collection, belongs to another collection.
/// A DuplicateNameException is thrown if this collection already has a column with the same
/// name (case insensitive).
///
private void BaseAdd(DataColumn column) {
if (column == null)
throw ExceptionBuilder.ArgumentNull("column");
if (column.table == table)
throw ExceptionBuilder.CannotAddColumn1(column.ColumnName);
if (column.table != null)
throw ExceptionBuilder.CannotAddColumn2(column.ColumnName);
if (column.ColumnName.Length == 0) {
column.ColumnName = AssignName();
}
RegisterColumnName(column.ColumnName, column, (DataTable)null);
try {
column.SetTable(table);
if (!table.fInitInProgress && column.Computed) {
if (column.DataExpression.DependsOn(column)) {
throw ExceptionBuilder.ExpressionCircular();
}
}
if (0 < table.RecordCapacity) {
// adding a column to table with existing rows
column.SetCapacity(table.RecordCapacity);
}
// fill column with default value.
for (int record = 0; record < table.RecordCapacity; record++) {
column.InitializeRecord(record);
}
if (table.DataSet != null) {
column.OnSetDataSet();
}
}
catch (Exception e) {
//
if (ADP.IsCatchableOrSecurityExceptionType(e)) {
UnregisterName(column.ColumnName);
}
throw;
}
}
///
/// BaseGroupSwitch will intelligently remove and add tables from the collection.
///
private void BaseGroupSwitch(DataColumn[] oldArray, int oldLength, DataColumn[] newArray, int newLength) {
// We're doing a smart diff of oldArray and newArray to find out what
// should be removed. We'll pass through oldArray and see if it exists
// in newArray, and if not, do remove work. newBase is an opt. in case
// the arrays have similar prefixes.
int newBase = 0;
for (int oldCur = 0; oldCur < oldLength; oldCur++) {
bool found = false;
for (int newCur = newBase; newCur < newLength; newCur++) {
if (oldArray[oldCur] == newArray[newCur]) {
if (newBase == newCur) {
newBase++;
}
found = true;
break;
}
}
if (!found) {
// This means it's in oldArray and not newArray. Remove it.
if (oldArray[oldCur].Table == table) {
BaseRemove(oldArray[oldCur]);
_list.Remove(oldArray[oldCur]);
oldArray[oldCur].SetOrdinalInternal(-1);
}
}
}
// Now, let's pass through news and those that don't belong, add them.
for (int newCur = 0; newCur < newLength; newCur++) {
if (newArray[newCur].Table != table) {
BaseAdd(newArray[newCur]);
_list.Add(newArray[newCur]);
}
newArray[newCur].SetOrdinalInternal(newCur);
}
}
///
/// Does verification on the column and it's name, and clears the column's dataSet pointer.
/// An ArgumentNullException is thrown if this column is null. An ArgumentException is thrown
/// if this column doesn't belong to this collection or if this column is part of a relationship.
/// An ArgumentException is thrown if another column's compute expression depends on this column.
///
private void BaseRemove(DataColumn column) {
if (CanRemove(column, true)) {
// remove
if (column.errors > 0) {
for (int i = 0; i < table.Rows.Count; i++) {
table.Rows[i].ClearError(column);
}
}
UnregisterName(column.ColumnName);
column.SetTable(null);
}
}
///
/// Checks
/// if
/// a given column can be removed from the collection.
///
public bool CanRemove(DataColumn column) {
return CanRemove(column, false);
}
internal bool CanRemove(DataColumn column, bool fThrowException) {
if (column == null) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.ArgumentNull("column");
}
if (column.table != table) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveColumn();
}
// allow subclasses to complain first.
table.OnRemoveColumnInternal(column);
// We need to make sure the column is not involved in any Relations or Constriants
if (table.primaryKey != null && table.primaryKey.Key.ContainsColumn(column)) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemovePrimaryKey();
}
for (int i = 0; i < table.ParentRelations.Count; i++) {
if (table.ParentRelations[i].ChildKey.ContainsColumn(column)) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveChildKey(table.ParentRelations[i].RelationName);
}
}
for (int i = 0; i < table.ChildRelations.Count; i++) {
if (table.ChildRelations[i].ParentKey.ContainsColumn(column)) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveChildKey(table.ChildRelations[i].RelationName);
}
}
for (int i = 0; i < table.Constraints.Count; i++) {
if (table.Constraints[i].ContainsColumn(column))
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveConstraint(table.Constraints[i].ConstraintName, table.Constraints[i].Table.TableName);
}
if (table.DataSet != null) {
for (ParentForeignKeyConstraintEnumerator en = new ParentForeignKeyConstraintEnumerator(table.DataSet, table); en.GetNext();) {
Constraint constraint = en.GetConstraint();
if (((ForeignKeyConstraint)constraint).ParentKey.ContainsColumn(column))
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveConstraint(constraint.ConstraintName, constraint.Table.TableName);
}
}
if (column.dependentColumns != null) {
for (int i = 0; i < column.dependentColumns.Count; i++) {
DataColumn col = column.dependentColumns[i];
if (fInClear && (col.Table == table || col.Table == null))
continue;
if (col.Table == null)
continue;
Debug.Assert(col.Computed, "invalid (non an expression) column in the expression dependent columns");
DataExpression expr = col.DataExpression;
if ((expr!= null) && (expr.DependsOn(column))) {
if (!fThrowException)
return false;
else
throw ExceptionBuilder.CannotRemoveExpression(col.ColumnName, col.Expression);
}
}
}
// SQLBU 429176: you can't remove a column participating in an index,
// while index events are suspended else the indexes won't be properly maintained.
// However, all the above checks should catch those participating columns.
// except when a column is in a DataView RowFilter or Sort clause
foreach (Index index in table.LiveIndexes) {
#if false
if (!Object.ReferenceEquals(index, column.sortIndex)) {
foreach (IndexField field in index.IndexFields) {
if (Object.ReferenceEquals(field.Column, column)) {
if (fThrowException) {
throw ExceptionBuilder.CannotRemoveExpression("DataView", column.ColumnName);
}
return false;
}
}
}
#endif
}
return true;
}
private void CheckIChangeTracking(DataColumn column) {
if (column.ImplementsIRevertibleChangeTracking) {
nColumnsImplementingIRevertibleChangeTracking++;
nColumnsImplementingIChangeTracking++;
AddColumnsImplementingIChangeTrackingList(column);
}
else if (column.ImplementsIChangeTracking) {
nColumnsImplementingIChangeTracking++;
AddColumnsImplementingIChangeTrackingList(column);
}
}
///
///
/// Clears the collection of any columns.
///
///
public void Clear() {
int oldLength = _list.Count;
DataColumn[] columns = new DataColumn[_list.Count];
_list.CopyTo(columns, 0);
OnCollectionChanging(RefreshEventArgs);
if (table.fInitInProgress && delayedAddRangeColumns != null) {
delayedAddRangeColumns = null;
}
try {
// this will smartly add and remove the appropriate tables.
fInClear = true;
BaseGroupSwitch(columns, oldLength, null, 0);
fInClear = false;
}
catch (Exception e) {
//
if (ADP.IsCatchableOrSecurityExceptionType(e)) {
// something messed up: restore to old values and throw
fInClear = false;
BaseGroupSwitch(null, 0, columns, oldLength);
_list.Clear();
for (int i = 0; i < oldLength; i++)
_list.Add(columns[i]);
}
throw;
}
_list.Clear();
table.ElementColumnCount = 0;
OnCollectionChanged(RefreshEventArgs);
}
///
/// Checks whether the collection contains a column with the specified name.
///
public bool Contains(string name) {
DataColumn column = columnFromName[name] as DataColumn;
if (column != null) {
return true;
}
return (IndexOfCaseInsensitive(name) >= 0);
}
internal bool Contains(string name, bool caseSensitive) {
DataColumn column = columnFromName[name] as DataColumn;
if (column != null) {
return true;
}
if (caseSensitive) { // above check did case sensitive check
return false;
}
else {
return (IndexOfCaseInsensitive(name) >= 0);
}
}
public void CopyTo(DataColumn[] array, int index) {
if (array==null)
throw ExceptionBuilder.ArgumentNull("array");
if (index < 0)
throw ExceptionBuilder.ArgumentOutOfRange("index");
if (array.Length - index < _list.Count)
throw ExceptionBuilder.InvalidOffsetLength();
for(int i = 0; i < _list.Count; ++i) {
array[index + i] = (DataColumn)_list[i];
}
}
///
///
/// Returns the index of a specified
///
public int IndexOf(DataColumn column) {
int columnCount = _list.Count;
for (int i = 0; i < columnCount; ++i) {
if (column == (DataColumn) _list[i]) {
return i;
}
}
return -1;
}
///
/// Returns the index of
/// a column specified by name.
///
public int IndexOf(string columnName) {
if ((null != columnName) && (0 < columnName.Length)) {
int count = Count;
DataColumn column = columnFromName[columnName] as DataColumn;
if (column != null) {
for (int j = 0; j < count; j++)
if (column == _list[j]) {
return j;
}
}
else {
int res = IndexOfCaseInsensitive(columnName);
return (res < 0) ? -1 : res;
}
}
return -1;
}
internal int IndexOfCaseInsensitive (string name) {
int hashcode = table.GetSpecialHashCode(name);
int cachedI = -1;
DataColumn column = null;
for (int i = 0; i < Count; i++) {
column = (DataColumn) _list[i];
if ( (hashcode == 0 || column._hashCode == 0 || column._hashCode == hashcode) &&
NamesEqual(column.ColumnName, name, false, table.Locale) != 0 ) {
if (cachedI == -1)
cachedI = i;
else
return -2;
}
}
return cachedI;
}
internal void FinishInitCollection() {
if (delayedAddRangeColumns != null) {
foreach(DataColumn column in delayedAddRangeColumns) {
if (column != null) {
Add(column);
}
}
foreach(DataColumn column in delayedAddRangeColumns) {
if (column != null) {
column.FinishInitInProgress();
}
}
delayedAddRangeColumns = null;
}
}
///
/// Makes a default name with the given index. e.g. Column1, Column2, ... Columni
///
private string MakeName(int index) {
if (1 == index) {
return "Column1";
}
return "Column" + index.ToString(System.Globalization.CultureInfo.InvariantCulture);
}
internal void MoveTo(DataColumn column, int newPosition) {
if (0 > newPosition || newPosition > Count -1) {
throw ExceptionBuilder.InvalidOrdinal("ordinal", newPosition);
}
if (column.ImplementsIChangeTracking) {
RemoveColumnsImplementingIChangeTrackingList(column);
}
_list.Remove(column);
_list.Insert(newPosition, column);
int count = _list.Count;
for (int i =0; i < count; i++) {
((DataColumn) _list[i]).SetOrdinalInternal(i);
}
CheckIChangeTracking(column);
OnCollectionChanged(new CollectionChangeEventArgs(CollectionChangeAction.Refresh, column));
}
///
///
/// Raises the
///
private void OnCollectionChanged(CollectionChangeEventArgs ccevent) {
table.UpdatePropertyDescriptorCollectionCache();
if ((null != ccevent) && !table.SchemaLoading && !table.fInitInProgress) {
DataColumn column = (DataColumn)ccevent.Element;
}
if (onCollectionChangedDelegate != null) {
onCollectionChangedDelegate(this, ccevent);
}
}
///
/// [To be supplied.]
///
private void OnCollectionChanging(CollectionChangeEventArgs ccevent) {
if (onCollectionChangingDelegate != null) {
onCollectionChangingDelegate(this, ccevent);
}
}
internal void OnColumnPropertyChanged(CollectionChangeEventArgs ccevent) {
table.UpdatePropertyDescriptorCollectionCache();
if (onColumnPropertyChangedDelegate != null) {
onColumnPropertyChangedDelegate(this, ccevent);
}
}
///
/// Registers this name as being used in the collection. Will throw an ArgumentException
/// if the name is already being used. Called by Add, All property, and Column.ColumnName property.
/// if the name is equivalent to the next default name to hand out, we increment our defaultNameIndex.
///
internal void RegisterColumnName(string name, DataColumn column, DataTable table) {
Debug.Assert (name != null);
Debug.Assert ((null == column) != (null == table), "RegisterColumnName wrong usage");
Object _exObject = columnFromName[name];
if (_exObject != null) {
if (_exObject is DataColumn) {
if (null != column) {
throw ExceptionBuilder.CannotAddDuplicate(name);
}
else {
throw ExceptionBuilder.CannotAddDuplicate3(name);
}
}
throw ExceptionBuilder.CannotAddDuplicate2(name);
}
//we need to check wether the tableName is the same of the
//next generable columnName and update defaultNameIndex accordingly
if ((null != table) && NamesEqual(name, MakeName(defaultNameIndex), true, this.table.Locale) != 0) {
do {
defaultNameIndex++;
} while (Contains(MakeName(defaultNameIndex)));
}
if (null != column) {
column._hashCode = this.table.GetSpecialHashCode(name);
columnFromName.Add(name, column);
}
else {
columnFromName.Add(name, table);
}
}
internal bool CanRegisterName(string name) {
Debug.Assert (name != null);
return (null == columnFromName[name]);
}
///
/// Removes the specified
///
public void Remove(DataColumn column) {
OnCollectionChanging(new CollectionChangeEventArgs(CollectionChangeAction.Remove, column));
BaseRemove(column);
ArrayRemove(column);
OnCollectionChanged(new CollectionChangeEventArgs(CollectionChangeAction.Remove, column));
// if the column is an element decrease the internal dataTable counter
if (column.ColumnMapping == MappingType.Element)
table.ElementColumnCount --;
}
///
/// Removes the
/// column at the specified index from the collection.
///
public void RemoveAt(int index) {
DataColumn dc = this[index];
if (dc == null)
throw ExceptionBuilder.ColumnOutOfRange(index);
Remove(dc);
}
///
/// Removes the
/// column with the specified name from the collection.
///
public void Remove(string name) {
DataColumn dc = this[name];
if (dc == null)
throw ExceptionBuilder.ColumnNotInTheTable(name, table.TableName);
Remove(dc);
}
///
/// Unregisters this name as no longer being used in the collection. Called by Remove, All property, and
/// Column.ColumnName property. If the name is equivalent to the last proposed default namem, we walk backwards
/// to find the next proper default name to hang out.
///
internal void UnregisterName(string name) {
Object obj = columnFromName[name];
if (obj != null) // sinc the HashTable is case-sensitive
columnFromName.Remove(name); // this is totally equivalent
if (NamesEqual(name, MakeName(defaultNameIndex - 1), true, table.Locale) != 0) {
do {
defaultNameIndex--;
} while (defaultNameIndex > 1 &&
!Contains(MakeName(defaultNameIndex - 1)));
}
}
private void AddColumnsImplementingIChangeTrackingList(DataColumn dataColumn) {
DataColumn[] columns = columnsImplementingIChangeTracking;
DataColumn[] tempColumns = new DataColumn[columns.Length +1];
columns.CopyTo(tempColumns, 0);
tempColumns[columns.Length] = dataColumn;
columnsImplementingIChangeTracking = tempColumns;
}
private void RemoveColumnsImplementingIChangeTrackingList(DataColumn dataColumn) {
DataColumn[] columns = columnsImplementingIChangeTracking;
DataColumn[] tempColumns = new DataColumn[columns.Length - 1];
for(int i = 0, j = 0; i < columns.Length; i++) {
if (columns[i] != dataColumn) {
tempColumns[j++] = columns[i];
}
}
columnsImplementingIChangeTracking = tempColumns;
}
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
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