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
- Claim.cs
- CredentialCache.cs
- SqlDataSourceEnumerator.cs
- OleStrCAMarshaler.cs
- StoryFragments.cs
- UndoManager.cs
- PackWebRequestFactory.cs
- TextWriterTraceListener.cs
- Debug.cs
- UnauthorizedWebPart.cs
- versioninfo.cs
- LicenseContext.cs
- ViewStateChangedEventArgs.cs
- TextTrailingWordEllipsis.cs
- StatusBarAutomationPeer.cs
- HashHelper.cs
- XamlContextStack.cs
- NamedPipeProcessProtocolHandler.cs
- RIPEMD160Managed.cs
- ToolStripSystemRenderer.cs
- TextElementEnumerator.cs
- DuplexChannel.cs
- HtmlShimManager.cs
- MemberRelationshipService.cs
- ChangeTracker.cs
- SoapAttributeOverrides.cs
- ProfileGroupSettings.cs
- BindingParameterCollection.cs
- DrawingDrawingContext.cs
- NonParentingControl.cs
- NativeMethods.cs
- Size.cs
- InfoCardRSACryptoProvider.cs
- SkinBuilder.cs
- PartialArray.cs
- ServiceDefaults.cs
- mongolianshape.cs
- EncryptionUtility.cs
- StructuralCache.cs
- Context.cs
- BrowserDefinition.cs
- TextBoxDesigner.cs
- XamlReader.cs
- MgmtResManager.cs
- RsaSecurityTokenParameters.cs
- NegationPusher.cs
- TransactionalPackage.cs
- WebPartCollection.cs
- RectKeyFrameCollection.cs
- EncryptedType.cs
- ObjectDataSourceDesigner.cs
- Region.cs
- CorePropertiesFilter.cs
- SafeRightsManagementSessionHandle.cs
- BamlRecordHelper.cs
- EmptyWithCancelationCheckWorkItem.cs
- MarginsConverter.cs
- EmptyElement.cs
- ExpressionBuilder.cs
- GeometryGroup.cs
- SafeLibraryHandle.cs
- SqlAggregateChecker.cs
- BCryptNative.cs
- FacetDescription.cs
- KoreanCalendar.cs
- CodeArgumentReferenceExpression.cs
- TextDecoration.cs
- OrderByQueryOptionExpression.cs
- MenuBase.cs
- TypeSource.cs
- SHA384Managed.cs
- TextServicesDisplayAttributePropertyRanges.cs
- DynamicDiscoSearcher.cs
- ListSortDescription.cs
- NameSpaceEvent.cs
- Empty.cs
- HtmlTitle.cs
- FastEncoderWindow.cs
- Binding.cs
- WindowsAuthenticationEventArgs.cs
- PropagatorResult.cs
- HttpBufferlessInputStream.cs
- ConnectionsZone.cs
- AdRotator.cs
- Subtract.cs
- KeyboardEventArgs.cs
- OleDbConnectionFactory.cs
- TagMapInfo.cs
- OleDbParameter.cs
- SqlDataReaderSmi.cs
- ProfileModule.cs
- RecipientInfo.cs
- ThicknessKeyFrameCollection.cs
- CLSCompliantAttribute.cs
- SpellerHighlightLayer.cs
- IgnoreSection.cs
- sqlpipe.cs
- ClusterRegistryConfigurationProvider.cs
- NamedElement.cs
- TreeNodeCollection.cs