Code:
/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / clr / src / BCL / System / Text / EncoderReplacementFallback.cs / 1305376 / EncoderReplacementFallback.cs
// ==++== // // Copyright (c) Microsoft Corporation. All rights reserved. // // ==--== // EncoderReplacementFallback.cs // namespace System.Text { using System; using System.Runtime; using System.Diagnostics.Contracts; [Serializable] public sealed class EncoderReplacementFallback : EncoderFallback { // Our variables private String strDefault; // Construction. Default replacement fallback uses no best fit and ? replacement string public EncoderReplacementFallback() : this("?") { } public EncoderReplacementFallback(String replacement) { // Must not be null if (replacement == null) throw new ArgumentNullException("replacement"); Contract.EndContractBlock(); // Make sure it doesn't have bad surrogate pairs bool bFoundHigh=false; for (int i = 0; i < replacement.Length; i++) { // Found a surrogate? if (Char.IsSurrogate(replacement,i)) { // High or Low? if (Char.IsHighSurrogate(replacement, i)) { // if already had a high one, stop if (bFoundHigh) break; // break & throw at the bFoundHIgh below bFoundHigh = true; } else { // Low, did we have a high? if (!bFoundHigh) { // Didn't have one, make if fail when we stop bFoundHigh = true; break; } // Clear flag bFoundHigh = false; } } // If last was high we're in trouble (not surrogate so not low surrogate, so break) else if (bFoundHigh) break; } if (bFoundHigh) throw new ArgumentException(Environment.GetResourceString("Argument_InvalidCharSequenceNoIndex", "replacement")); strDefault = replacement; } public String DefaultString { get { return strDefault; } } public override EncoderFallbackBuffer CreateFallbackBuffer() { return new EncoderReplacementFallbackBuffer(this); } // Maximum number of characters that this instance of this fallback could return public override int MaxCharCount { #if !FEATURE_CORECLR [TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")] #endif get { return strDefault.Length; } } #if !FEATURE_CORECLR [TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")] #endif public override bool Equals(Object value) { EncoderReplacementFallback that = value as EncoderReplacementFallback; if (that != null) { return (this.strDefault == that.strDefault); } return (false); } public override int GetHashCode() { return strDefault.GetHashCode(); } } public sealed class EncoderReplacementFallbackBuffer : EncoderFallbackBuffer { // Store our default string private String strDefault; int fallbackCount = -1; int fallbackIndex = -1; // Construction public EncoderReplacementFallbackBuffer(EncoderReplacementFallback fallback) { // 2X in case we're a surrogate pair this.strDefault = fallback.DefaultString + fallback.DefaultString; } // Fallback Methods public override bool Fallback(char charUnknown, int index) { // If we had a buffer already we're being recursive, throw, it's probably at the suspect // character in our array. if (fallbackCount >= 1) { // If we're recursive we may still have something in our buffer that makes this a surrogate if (char.IsHighSurrogate(charUnknown) && fallbackCount >= 0 && char.IsLowSurrogate(strDefault[fallbackIndex+1])) ThrowLastCharRecursive(Char.ConvertToUtf32(charUnknown, strDefault[fallbackIndex+1])); // Nope, just one character ThrowLastCharRecursive(unchecked((int)charUnknown)); } // Go ahead and get our fallback // Divide by 2 because we aren't a surrogate pair fallbackCount = strDefault.Length/2; fallbackIndex = -1; return fallbackCount != 0; } public override bool Fallback(char charUnknownHigh, char charUnknownLow, int index) { // Double check input surrogate pair if (!Char.IsHighSurrogate(charUnknownHigh)) throw new ArgumentOutOfRangeException("charUnknownHigh", Environment.GetResourceString("ArgumentOutOfRange_Range", 0xD800, 0xDBFF)); if (!Char.IsLowSurrogate(charUnknownLow)) throw new ArgumentOutOfRangeException("CharUnknownLow", Environment.GetResourceString("ArgumentOutOfRange_Range", 0xDC00, 0xDFFF)); Contract.EndContractBlock(); // If we had a buffer already we're being recursive, throw, it's probably at the suspect // character in our array. if (fallbackCount >= 1) ThrowLastCharRecursive(Char.ConvertToUtf32(charUnknownHigh, charUnknownLow)); // Go ahead and get our fallback fallbackCount = strDefault.Length; fallbackIndex = -1; return fallbackCount != 0; } public override char GetNextChar() { // We want it to get < 0 because == 0 means that the current/last character is a fallback // and we need to detect recursion. We could have a flag but we already have this counter. fallbackCount--; fallbackIndex++; // Do we have anything left? 0 is now last fallback char, negative is nothing left if (fallbackCount < 0) return '\0'; // Need to get it out of the buffer. // Make sure it didn't wrap from the fast count-- path if (fallbackCount == int.MaxValue) { fallbackCount = -1; return '\0'; } // Now make sure its in the expected range Contract.Assert(fallbackIndex < strDefault.Length && fallbackIndex >= 0, "Index exceeds buffer range"); return strDefault[fallbackIndex]; } public override bool MovePrevious() { // Back up one, only if we just processed the last character (or earlier) if (fallbackCount >= -1 && fallbackIndex >= 0) { fallbackIndex--; fallbackCount++; return true; } // Return false 'cause we couldn't do it. return false; } // How many characters left to output? public override int Remaining { get { // Our count is 0 for 1 character left. return (fallbackCount < 0) ? 0 : fallbackCount; } } // Clear the buffer [System.Security.SecuritySafeCritical] // auto-generated public override unsafe void Reset() { fallbackCount = -1; fallbackIndex = 0; charStart = null; bFallingBack = false; } } } // 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
- TabPanel.cs
- ClientConvert.cs
- ConnectionConsumerAttribute.cs
- Comparer.cs
- Group.cs
- MetadataPropertyvalue.cs
- StreamAsIStream.cs
- SmiConnection.cs
- PeerPresenceInfo.cs
- IgnoreSectionHandler.cs
- InvalidOperationException.cs
- PreviewPageInfo.cs
- DiagnosticsConfigurationHandler.cs
- ProviderMetadata.cs
- DetailsViewUpdateEventArgs.cs
- IERequestCache.cs
- ProvideValueServiceProvider.cs
- TableLayoutSettings.cs
- EndpointAddress.cs
- DesignerCommandSet.cs
- DropShadowBitmapEffect.cs
- Freezable.cs
- BamlReader.cs
- MetadataCollection.cs
- MemberInitExpression.cs
- TextEncodedRawTextWriter.cs
- ZipPackagePart.cs
- ConnectionPoint.cs
- MimeFormImporter.cs
- OneOf.cs
- ProgressiveCrcCalculatingStream.cs
- XmlDataImplementation.cs
- SectionInput.cs
- TabRenderer.cs
- ToolStripLabel.cs
- TypeInformation.cs
- BaseProcessProtocolHandler.cs
- MessageEncodingBindingElementImporter.cs
- InheritablePropertyChangeInfo.cs
- ItemsPanelTemplate.cs
- RouteValueDictionary.cs
- ListBoxChrome.cs
- Typography.cs
- GridViewRowEventArgs.cs
- Crc32.cs
- SettingsContext.cs
- SystemResources.cs
- WebPartDisplayModeEventArgs.cs
- Types.cs
- DecoderExceptionFallback.cs
- OverrideMode.cs
- ParentQuery.cs
- FrameworkContentElement.cs
- UriScheme.cs
- DataTransferEventArgs.cs
- NamespaceMapping.cs
- ResXBuildProvider.cs
- InnerItemCollectionView.cs
- SchemaEntity.cs
- NullableDoubleAverageAggregationOperator.cs
- SqlConnectionHelper.cs
- Site.cs
- OleDbSchemaGuid.cs
- DocumentReferenceCollection.cs
- ProtectedProviderSettings.cs
- DesignTimeResourceProviderFactoryAttribute.cs
- SoapRpcMethodAttribute.cs
- FileInfo.cs
- Stack.cs
- ApplicationDirectoryMembershipCondition.cs
- BroadcastEventHelper.cs
- PropertyPathWorker.cs
- DataColumnMapping.cs
- RoutedCommand.cs
- AsynchronousChannel.cs
- ConstantProjectedSlot.cs
- ImageAutomationPeer.cs
- SiteMapNodeItem.cs
- StdValidatorsAndConverters.cs
- SqlParameterCollection.cs
- StateMachineSubscription.cs
- Rectangle.cs
- NavigatorOutput.cs
- ProcessHost.cs
- Interfaces.cs
- ChameleonKey.cs
- PropertyOrder.cs
- DataGridSortCommandEventArgs.cs
- InsufficientMemoryException.cs
- XamlDesignerSerializationManager.cs
- __Error.cs
- SqlServices.cs
- PersonalizableTypeEntry.cs
- _ProxyChain.cs
- DivideByZeroException.cs
- CatalogPartCollection.cs
- Attachment.cs
- HashStream.cs
- AnalyzedTree.cs
- ChildTable.cs