Code:
/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / Data / System / Data / ConstraintEnumerator.cs / 1305376 / ConstraintEnumerator.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //[....] //[....] //----------------------------------------------------------------------------- namespace System.Data { using System; using System.Diagnostics; using System.Collections; using System.ComponentModel; ////// ConstraintEnumerator is an object for enumerating all constraints in a DataSet /// internal class ConstraintEnumerator { System.Collections.IEnumerator tables; System.Collections.IEnumerator constraints; Constraint currentObject; public ConstraintEnumerator(DataSet dataSet) { tables = (dataSet != null) ? dataSet.Tables.GetEnumerator() : null; currentObject = null; } public bool GetNext() { Constraint candidate; currentObject = null; while (tables != null) { if (constraints == null) { if (!tables.MoveNext()) { tables = null; return false; } constraints = ((DataTable)tables.Current).Constraints.GetEnumerator(); } if (!constraints.MoveNext()) { constraints = null; continue; } Debug.Assert(constraints.Current is Constraint, "ConstraintEnumerator, contains object which is not constraint"); candidate = (Constraint)constraints.Current; if (IsValidCandidate(candidate)) { currentObject = candidate; return true; } } return false; } public Constraint GetConstraint() { // If currentObject is null we are before first GetNext or after last GetNext--consumer is bad Debug.Assert (currentObject != null, "GetObject should never be called w/ null currentObject."); return currentObject; } protected virtual bool IsValidCandidate(Constraint constraint) { return true; } protected Constraint CurrentObject { get { return currentObject; } } } internal class ForeignKeyConstraintEnumerator : ConstraintEnumerator { public ForeignKeyConstraintEnumerator(DataSet dataSet) : base(dataSet) { } protected override bool IsValidCandidate(Constraint constraint) { return(constraint is ForeignKeyConstraint); } public ForeignKeyConstraint GetForeignKeyConstraint() { // If CurrentObject is null we are before first GetNext or after last GetNext--consumer is bad Debug.Assert (CurrentObject != null, "GetObject should never be called w/ null currentObject."); return(ForeignKeyConstraint)CurrentObject; } } internal sealed class ChildForeignKeyConstraintEnumerator : ForeignKeyConstraintEnumerator { // this is the table to do comparisons against DataTable table; public ChildForeignKeyConstraintEnumerator(DataSet dataSet, DataTable inTable) : base(dataSet) { this.table = inTable; } protected override bool IsValidCandidate(Constraint constraint) { return((constraint is ForeignKeyConstraint) && (((ForeignKeyConstraint)constraint).Table == table)); } } internal sealed class ParentForeignKeyConstraintEnumerator : ForeignKeyConstraintEnumerator { // this is the table to do comparisons against DataTable table; public ParentForeignKeyConstraintEnumerator(DataSet dataSet, DataTable inTable) : base(dataSet) { this.table = inTable; } protected override bool IsValidCandidate(Constraint constraint) { return((constraint is ForeignKeyConstraint) && (((ForeignKeyConstraint)constraint).RelatedTable == table)); } } } // 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.Diagnostics; using System.Collections; using System.ComponentModel; ////// ConstraintEnumerator is an object for enumerating all constraints in a DataSet /// internal class ConstraintEnumerator { System.Collections.IEnumerator tables; System.Collections.IEnumerator constraints; Constraint currentObject; public ConstraintEnumerator(DataSet dataSet) { tables = (dataSet != null) ? dataSet.Tables.GetEnumerator() : null; currentObject = null; } public bool GetNext() { Constraint candidate; currentObject = null; while (tables != null) { if (constraints == null) { if (!tables.MoveNext()) { tables = null; return false; } constraints = ((DataTable)tables.Current).Constraints.GetEnumerator(); } if (!constraints.MoveNext()) { constraints = null; continue; } Debug.Assert(constraints.Current is Constraint, "ConstraintEnumerator, contains object which is not constraint"); candidate = (Constraint)constraints.Current; if (IsValidCandidate(candidate)) { currentObject = candidate; return true; } } return false; } public Constraint GetConstraint() { // If currentObject is null we are before first GetNext or after last GetNext--consumer is bad Debug.Assert (currentObject != null, "GetObject should never be called w/ null currentObject."); return currentObject; } protected virtual bool IsValidCandidate(Constraint constraint) { return true; } protected Constraint CurrentObject { get { return currentObject; } } } internal class ForeignKeyConstraintEnumerator : ConstraintEnumerator { public ForeignKeyConstraintEnumerator(DataSet dataSet) : base(dataSet) { } protected override bool IsValidCandidate(Constraint constraint) { return(constraint is ForeignKeyConstraint); } public ForeignKeyConstraint GetForeignKeyConstraint() { // If CurrentObject is null we are before first GetNext or after last GetNext--consumer is bad Debug.Assert (CurrentObject != null, "GetObject should never be called w/ null currentObject."); return(ForeignKeyConstraint)CurrentObject; } } internal sealed class ChildForeignKeyConstraintEnumerator : ForeignKeyConstraintEnumerator { // this is the table to do comparisons against DataTable table; public ChildForeignKeyConstraintEnumerator(DataSet dataSet, DataTable inTable) : base(dataSet) { this.table = inTable; } protected override bool IsValidCandidate(Constraint constraint) { return((constraint is ForeignKeyConstraint) && (((ForeignKeyConstraint)constraint).Table == table)); } } internal sealed class ParentForeignKeyConstraintEnumerator : ForeignKeyConstraintEnumerator { // this is the table to do comparisons against DataTable table; public ParentForeignKeyConstraintEnumerator(DataSet dataSet, DataTable inTable) : base(dataSet) { this.table = inTable; } protected override bool IsValidCandidate(Constraint constraint) { return((constraint is ForeignKeyConstraint) && (((ForeignKeyConstraint)constraint).RelatedTable == table)); } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- TextFormatter.cs
- Color.cs
- ExtractCollection.cs
- HtmlInputFile.cs
- TextWriterTraceListener.cs
- SpellCheck.cs
- Point3DValueSerializer.cs
- SqlXmlStorage.cs
- AdapterDictionary.cs
- Repeater.cs
- AdapterUtil.cs
- IISUnsafeMethods.cs
- HttpChannelHelpers.cs
- ObjectFactoryCodeDomTreeGenerator.cs
- NonParentingControl.cs
- LinkedList.cs
- WebServiceEnumData.cs
- ValidationSummary.cs
- XmlSchemaSimpleTypeRestriction.cs
- DataTableMapping.cs
- SessionState.cs
- SystemMulticastIPAddressInformation.cs
- ObjectView.cs
- TimerEventSubscription.cs
- COM2PictureConverter.cs
- LeaseManager.cs
- WindowsFormsHelpers.cs
- DynamicMethod.cs
- ExpressionsCollectionConverter.cs
- ExpressionBuilder.cs
- ProfileGroupSettings.cs
- CodeSnippetExpression.cs
- WebPartManager.cs
- StatusBarDrawItemEvent.cs
- XmlBindingWorker.cs
- SinglePhaseEnlistment.cs
- BoolExpressionVisitors.cs
- LinkLabel.cs
- DataGridViewRowConverter.cs
- DateTimeValueSerializerContext.cs
- DataBoundControlHelper.cs
- XmlSiteMapProvider.cs
- commandenforcer.cs
- KerberosSecurityTokenProvider.cs
- ObjectStateEntryBaseUpdatableDataRecord.cs
- FindCriteriaCD1.cs
- Accessors.cs
- TemplatedAdorner.cs
- _SslStream.cs
- DataPager.cs
- ErrorHandler.cs
- SelectedDatesCollection.cs
- DataGridCaption.cs
- VectorAnimation.cs
- EventLogTraceListener.cs
- LinqDataSourceStatusEventArgs.cs
- ToolStripSystemRenderer.cs
- SelectionProcessor.cs
- SegmentInfo.cs
- DesignTimeTemplateParser.cs
- InstanceDataCollection.cs
- HtmlTable.cs
- PageHandlerFactory.cs
- ViewService.cs
- counter.cs
- FileDialog_Vista_Interop.cs
- DispatcherHookEventArgs.cs
- StringUtil.cs
- CodeIterationStatement.cs
- ConnectivityStatus.cs
- PropertyManager.cs
- BehaviorDragDropEventArgs.cs
- XPathParser.cs
- SortQueryOperator.cs
- BaseValidator.cs
- InternalBufferManager.cs
- PagedControl.cs
- KeyToListMap.cs
- SQLGuidStorage.cs
- AliasedExpr.cs
- UnicodeEncoding.cs
- RotateTransform.cs
- NodeInfo.cs
- SecurityTokenReferenceStyle.cs
- StoreItemCollection.cs
- ControlBuilderAttribute.cs
- XamlReaderHelper.cs
- RewritingSimplifier.cs
- BindingElementCollection.cs
- RoutedUICommand.cs
- IndentTextWriter.cs
- Tile.cs
- SQLDateTimeStorage.cs
- DesignerDataConnection.cs
- ToolStripPanelCell.cs
- RotationValidation.cs
- Page.cs
- MappedMetaModel.cs
- RenderingBiasValidation.cs
- WebRequestModulesSection.cs