DataRowView.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / Data / System / Data / DataRowView.cs / 1305376 / DataRowView.cs
                        

                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
// [....]
//----------------------------------------------------------------------------- 
 
namespace System.Data {
    using System.Diagnostics; 
    using System.ComponentModel;

    public class DataRowView : ICustomTypeDescriptor, System.ComponentModel.IEditableObject, System.ComponentModel.IDataErrorInfo, System.ComponentModel.INotifyPropertyChanged {
 
        private readonly DataView dataView;
        private readonly DataRow _row; 
        private bool delayBeginEdit; 

        private static PropertyDescriptorCollection zeroPropertyDescriptorCollection = new PropertyDescriptorCollection(null); 

        /// 
        /// When the PropertyChanged event happens, it must happen on the same DataRowView reference.
        /// This is so a generic event handler like Windows Presentation Foundation can redirect as appropriate. 
        /// Having DataView.Equals is not sufficient for WPF, because two different instances may be equal but not equivalent.
        /// For DataRowView, if two instances are equal then they are equivalent. 
        ///  
        private System.ComponentModel.PropertyChangedEventHandler  onPropertyChanged;
 
        internal DataRowView(DataView dataView, DataRow row)
        {
            this.dataView = dataView;
            this._row = row; 
        }
 
        ///  
        /// Checks for same reference instead of equivalent  or .
        /// 
        /// Necessary for ListChanged event handlers to use data structures that use the default to
        ///  instead of 
        /// to understand if they need to add a  event handler.
        ///  
        /// 
        public override bool Equals(object other) { 
            return Object.ReferenceEquals(this, other); 
        }
 
        /// Hashcode of 
        public override Int32 GetHashCode() {
            // Everett compatability, must return hashcode for DataRow
            // this does prevent using this object in collections like Hashtable 
            // which use the hashcode as an immutable value to identify this object
            // user could/should have used the DataRow property instead of the hashcode 
            return Row.GetHashCode(); 
        }
 
        public DataView DataView {
            get {
                return dataView;
            } 
        }
 
        internal int ObjectID { 
            get { return _row.ObjectID; }
        } 

        /// Gets or sets a value in specified column.
        /// Specified column index.
        /// Uses either  or  to access  
        ///  when setting a value.
        ///  
        public object this[int ndx] { 
            get {
                return Row[ndx, RowVersionDefault]; 
            }
            set {
                if (!dataView.AllowEdit && !IsNew) {
                    throw ExceptionBuilder.CanNotEdit(); 
                }
                SetColumnValue(dataView.Table.Columns[ndx], value); 
            } 
        }
 
        /// Gets the specified column value or related child view or sets a value in specified column.
        /// Specified column or relation name when getting.  Specified column name when setting.
        ///  when  is ambigous.
        /// Unmatched  when getting a value. 
        /// Unmatched  when setting a value.
        ///  when setting a value. 
        public object this[string property] { 
            get {
                DataColumn column = dataView.Table.Columns[property]; 
                if (null != column) {
                    return Row[column, RowVersionDefault];
                }
                else if (dataView.Table.DataSet != null && dataView.Table.DataSet.Relations.Contains(property)) { 
                    return CreateChildView(property);
                } 
                throw ExceptionBuilder.PropertyNotFound(property, dataView.Table.TableName); 
            }
            set { 
                DataColumn column = dataView.Table.Columns[property];
                if (null == column) {
                    throw ExceptionBuilder.SetFailed(property);
                } 
                if (!dataView.AllowEdit && !IsNew) {
                    throw ExceptionBuilder.CanNotEdit(); 
                } 
                SetColumnValue(column, value);
            } 
        }

        // IDataErrorInfo stuff
        string System.ComponentModel.IDataErrorInfo.this[string colName] { 
            get {
                return Row.GetColumnError(colName); 
            } 
        }
 
        string System.ComponentModel.IDataErrorInfo.Error {
            get {
                return Row.RowError;
            } 
        }
 
        ///  
        /// Gets the current version description of the 
        /// in relation to  
        /// 
        /// Either  or 
        public DataRowVersion RowVersion {
            get { 
                return (RowVersionDefault & ~DataRowVersion.Proposed);
            } 
        } 

        /// Either  or  
        private DataRowVersion RowVersionDefault {
            get {
                return Row.GetDefaultRowVersion(dataView.RowStateFilter);
            } 
        }
 
        internal int GetRecord() { 
            return Row.GetRecordFromVersion(RowVersionDefault);
        } 

        internal object GetColumnValue(DataColumn column) {
            return Row[column, RowVersionDefault];
        } 

        internal void SetColumnValue(DataColumn column, object value) { 
            if (delayBeginEdit) { 
                delayBeginEdit = false;
                Row.BeginEdit(); 
            }
            if (DataRowVersion.Original == RowVersionDefault) {
                throw ExceptionBuilder.SetFailed(column.ColumnName);
            } 
            Row[column] = value;
        } 
 
        /// 
        /// Returns a  
        /// for the child 
        /// with the specified .
        /// 
        /// Specified . 
        /// null or mismatch between  and .
        public DataView CreateChildView(DataRelation relation) { 
            if (relation == null || relation.ParentKey.Table != DataView.Table) { 
                throw ExceptionBuilder.CreateChildView();
            } 
            int record = GetRecord();
            object[] values = relation.ParentKey.GetKeyValues(record);
            RelatedView childView = new RelatedView(relation.ChildColumnsReference, values);
            childView.SetIndex("", DataViewRowState.CurrentRows, null); // finish construction via RelatedView.SetIndex 
            childView.SetDataViewManager(DataView.DataViewManager);
            return childView; 
        } 

        ///  
        /// Specified  name.
        /// Unmatched .
        public DataView CreateChildView(string relationName) {
            return CreateChildView(DataView.Table.ChildRelations[relationName]); 
        }
 
        public DataRow Row { 
            get {
                return _row; 
            }
        }

        public void BeginEdit() { 
            delayBeginEdit = true;
        } 
 
        public void CancelEdit() {
            DataRow tmpRow = Row; 
            if (IsNew) {
                dataView.FinishAddNew(false);
            }
            else { 
                tmpRow.CancelEdit();
            } 
            delayBeginEdit = false; 
        }
 
        public void EndEdit() {
            if (IsNew) {
                dataView.FinishAddNew(true);
            } 
            else {
                Row.EndEdit(); 
            } 
            delayBeginEdit = false;
        } 

        public bool IsNew {
            get {
                return (_row == dataView.addNewRow); 
            }
        } 
 
        public bool IsEdit {
            get { 
                return (
                    Row.HasVersion(DataRowVersion.Proposed) ||  // It was edited or
                    delayBeginEdit);                            // DataRowView.BegingEdit() was called, but not edited yet.
            } 
        }
 
        public void Delete() { 
            dataView.Delete(Row);
        } 

        #region ICustomTypeDescriptor

        AttributeCollection ICustomTypeDescriptor.GetAttributes() { 
            return new AttributeCollection((Attribute[])null);
        } 
 
        string ICustomTypeDescriptor.GetClassName() {
            return null; 
        }

        string ICustomTypeDescriptor.GetComponentName() {
            return null; 
        }
 
        TypeConverter ICustomTypeDescriptor.GetConverter() { 
            return null;
        } 

        EventDescriptor ICustomTypeDescriptor.GetDefaultEvent() {
            return null;
        } 

        PropertyDescriptor ICustomTypeDescriptor.GetDefaultProperty() { 
            return null; 
        }
 
        object ICustomTypeDescriptor.GetEditor(Type editorBaseType) {
            return null;
        }
 
        EventDescriptorCollection ICustomTypeDescriptor.GetEvents() {
            return new EventDescriptorCollection(null); 
        } 

        EventDescriptorCollection ICustomTypeDescriptor.GetEvents(Attribute[] attributes) { 
            return new EventDescriptorCollection(null);
        }

        PropertyDescriptorCollection ICustomTypeDescriptor.GetProperties() { 
            return((ICustomTypeDescriptor)this).GetProperties(null);
        } 
 
        PropertyDescriptorCollection ICustomTypeDescriptor.GetProperties(Attribute[] attributes) {
            return (dataView.Table != null ? dataView.Table.GetPropertyDescriptorCollection(attributes) : zeroPropertyDescriptorCollection); 
        }

        object ICustomTypeDescriptor.GetPropertyOwner(PropertyDescriptor pd) {
            return this; 
        }
 
        #endregion 

        public event PropertyChangedEventHandler PropertyChanged { 
            add {
                onPropertyChanged += value;
            }
            remove { 
                onPropertyChanged -= value;
            } 
 
        }
 
        internal void RaisePropertyChangedEvent (string propName){
            // Do not try catch, we would mask users bugs. if they throw we would catch
            if (onPropertyChanged != null) {
                onPropertyChanged (this, new PropertyChangedEventArgs(propName)); 
            }
        } 
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
// [....]
//----------------------------------------------------------------------------- 
 
namespace System.Data {
    using System.Diagnostics; 
    using System.ComponentModel;

    public class DataRowView : ICustomTypeDescriptor, System.ComponentModel.IEditableObject, System.ComponentModel.IDataErrorInfo, System.ComponentModel.INotifyPropertyChanged {
 
        private readonly DataView dataView;
        private readonly DataRow _row; 
        private bool delayBeginEdit; 

        private static PropertyDescriptorCollection zeroPropertyDescriptorCollection = new PropertyDescriptorCollection(null); 

        /// 
        /// When the PropertyChanged event happens, it must happen on the same DataRowView reference.
        /// This is so a generic event handler like Windows Presentation Foundation can redirect as appropriate. 
        /// Having DataView.Equals is not sufficient for WPF, because two different instances may be equal but not equivalent.
        /// For DataRowView, if two instances are equal then they are equivalent. 
        ///  
        private System.ComponentModel.PropertyChangedEventHandler  onPropertyChanged;
 
        internal DataRowView(DataView dataView, DataRow row)
        {
            this.dataView = dataView;
            this._row = row; 
        }
 
        ///  
        /// Checks for same reference instead of equivalent  or .
        /// 
        /// Necessary for ListChanged event handlers to use data structures that use the default to
        ///  instead of 
        /// to understand if they need to add a  event handler.
        ///  
        /// 
        public override bool Equals(object other) { 
            return Object.ReferenceEquals(this, other); 
        }
 
        /// Hashcode of 
        public override Int32 GetHashCode() {
            // Everett compatability, must return hashcode for DataRow
            // this does prevent using this object in collections like Hashtable 
            // which use the hashcode as an immutable value to identify this object
            // user could/should have used the DataRow property instead of the hashcode 
            return Row.GetHashCode(); 
        }
 
        public DataView DataView {
            get {
                return dataView;
            } 
        }
 
        internal int ObjectID { 
            get { return _row.ObjectID; }
        } 

        /// Gets or sets a value in specified column.
        /// Specified column index.
        /// Uses either  or  to access  
        ///  when setting a value.
        ///  
        public object this[int ndx] { 
            get {
                return Row[ndx, RowVersionDefault]; 
            }
            set {
                if (!dataView.AllowEdit && !IsNew) {
                    throw ExceptionBuilder.CanNotEdit(); 
                }
                SetColumnValue(dataView.Table.Columns[ndx], value); 
            } 
        }
 
        /// Gets the specified column value or related child view or sets a value in specified column.
        /// Specified column or relation name when getting.  Specified column name when setting.
        ///  when  is ambigous.
        /// Unmatched  when getting a value. 
        /// Unmatched  when setting a value.
        ///  when setting a value. 
        public object this[string property] { 
            get {
                DataColumn column = dataView.Table.Columns[property]; 
                if (null != column) {
                    return Row[column, RowVersionDefault];
                }
                else if (dataView.Table.DataSet != null && dataView.Table.DataSet.Relations.Contains(property)) { 
                    return CreateChildView(property);
                } 
                throw ExceptionBuilder.PropertyNotFound(property, dataView.Table.TableName); 
            }
            set { 
                DataColumn column = dataView.Table.Columns[property];
                if (null == column) {
                    throw ExceptionBuilder.SetFailed(property);
                } 
                if (!dataView.AllowEdit && !IsNew) {
                    throw ExceptionBuilder.CanNotEdit(); 
                } 
                SetColumnValue(column, value);
            } 
        }

        // IDataErrorInfo stuff
        string System.ComponentModel.IDataErrorInfo.this[string colName] { 
            get {
                return Row.GetColumnError(colName); 
            } 
        }
 
        string System.ComponentModel.IDataErrorInfo.Error {
            get {
                return Row.RowError;
            } 
        }
 
        ///  
        /// Gets the current version description of the 
        /// in relation to  
        /// 
        /// Either  or 
        public DataRowVersion RowVersion {
            get { 
                return (RowVersionDefault & ~DataRowVersion.Proposed);
            } 
        } 

        /// Either  or  
        private DataRowVersion RowVersionDefault {
            get {
                return Row.GetDefaultRowVersion(dataView.RowStateFilter);
            } 
        }
 
        internal int GetRecord() { 
            return Row.GetRecordFromVersion(RowVersionDefault);
        } 

        internal object GetColumnValue(DataColumn column) {
            return Row[column, RowVersionDefault];
        } 

        internal void SetColumnValue(DataColumn column, object value) { 
            if (delayBeginEdit) { 
                delayBeginEdit = false;
                Row.BeginEdit(); 
            }
            if (DataRowVersion.Original == RowVersionDefault) {
                throw ExceptionBuilder.SetFailed(column.ColumnName);
            } 
            Row[column] = value;
        } 
 
        /// 
        /// Returns a  
        /// for the child 
        /// with the specified .
        /// 
        /// Specified . 
        /// null or mismatch between  and .
        public DataView CreateChildView(DataRelation relation) { 
            if (relation == null || relation.ParentKey.Table != DataView.Table) { 
                throw ExceptionBuilder.CreateChildView();
            } 
            int record = GetRecord();
            object[] values = relation.ParentKey.GetKeyValues(record);
            RelatedView childView = new RelatedView(relation.ChildColumnsReference, values);
            childView.SetIndex("", DataViewRowState.CurrentRows, null); // finish construction via RelatedView.SetIndex 
            childView.SetDataViewManager(DataView.DataViewManager);
            return childView; 
        } 

        ///  
        /// Specified  name.
        /// Unmatched .
        public DataView CreateChildView(string relationName) {
            return CreateChildView(DataView.Table.ChildRelations[relationName]); 
        }
 
        public DataRow Row { 
            get {
                return _row; 
            }
        }

        public void BeginEdit() { 
            delayBeginEdit = true;
        } 
 
        public void CancelEdit() {
            DataRow tmpRow = Row; 
            if (IsNew) {
                dataView.FinishAddNew(false);
            }
            else { 
                tmpRow.CancelEdit();
            } 
            delayBeginEdit = false; 
        }
 
        public void EndEdit() {
            if (IsNew) {
                dataView.FinishAddNew(true);
            } 
            else {
                Row.EndEdit(); 
            } 
            delayBeginEdit = false;
        } 

        public bool IsNew {
            get {
                return (_row == dataView.addNewRow); 
            }
        } 
 
        public bool IsEdit {
            get { 
                return (
                    Row.HasVersion(DataRowVersion.Proposed) ||  // It was edited or
                    delayBeginEdit);                            // DataRowView.BegingEdit() was called, but not edited yet.
            } 
        }
 
        public void Delete() { 
            dataView.Delete(Row);
        } 

        #region ICustomTypeDescriptor

        AttributeCollection ICustomTypeDescriptor.GetAttributes() { 
            return new AttributeCollection((Attribute[])null);
        } 
 
        string ICustomTypeDescriptor.GetClassName() {
            return null; 
        }

        string ICustomTypeDescriptor.GetComponentName() {
            return null; 
        }
 
        TypeConverter ICustomTypeDescriptor.GetConverter() { 
            return null;
        } 

        EventDescriptor ICustomTypeDescriptor.GetDefaultEvent() {
            return null;
        } 

        PropertyDescriptor ICustomTypeDescriptor.GetDefaultProperty() { 
            return null; 
        }
 
        object ICustomTypeDescriptor.GetEditor(Type editorBaseType) {
            return null;
        }
 
        EventDescriptorCollection ICustomTypeDescriptor.GetEvents() {
            return new EventDescriptorCollection(null); 
        } 

        EventDescriptorCollection ICustomTypeDescriptor.GetEvents(Attribute[] attributes) { 
            return new EventDescriptorCollection(null);
        }

        PropertyDescriptorCollection ICustomTypeDescriptor.GetProperties() { 
            return((ICustomTypeDescriptor)this).GetProperties(null);
        } 
 
        PropertyDescriptorCollection ICustomTypeDescriptor.GetProperties(Attribute[] attributes) {
            return (dataView.Table != null ? dataView.Table.GetPropertyDescriptorCollection(attributes) : zeroPropertyDescriptorCollection); 
        }

        object ICustomTypeDescriptor.GetPropertyOwner(PropertyDescriptor pd) {
            return this; 
        }
 
        #endregion 

        public event PropertyChangedEventHandler PropertyChanged { 
            add {
                onPropertyChanged += value;
            }
            remove { 
                onPropertyChanged -= value;
            } 
 
        }
 
        internal void RaisePropertyChangedEvent (string propName){
            // Do not try catch, we would mask users bugs. if they throw we would catch
            if (onPropertyChanged != null) {
                onPropertyChanged (this, new PropertyChangedEventArgs(propName)); 
            }
        } 
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.

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