Code:
/ DotNET / DotNET / 8.0 / untmp / whidbey / REDBITS / ndp / fx / src / Designer / System / data / design / ConversionHelper.cs / 1 / ConversionHelper.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All Rights Reserved. // Information Contained Herein is Proprietary and Confidential. // //----------------------------------------------------------------------------- namespace System.Data.Design { using System; internal class ConversionHelper { ////// Private contstructor to avoid class being instantiated. /// private ConversionHelper() { } // Convertion table for the System.Convert class. Info taken from Convert.cs. // Lines represent the 'From', columns represent the 'To'. // E.g. line 1, col 2 indicates that a boolean cannot be converted to a char. // This table can be compressed much further but it makes the code less readable. private static Int16[] urtConversionTable = { 0x5FFD, /*101111111111101*/ // Boolean 0x3FE1, /*011111111100001*/ // Char 0x7FFD, /*111111111111101*/ // SByte 0x7FFD, /*111111111111101*/ // Byte 0x7FFD, /*111111111111101*/ // Int16 0x7FFD, /*111111111111101*/ // UInt16 0x7FFD, /*111111111111101*/ // Int32 0x7FFD, /*111111111111101*/ // UInt32 0x7FFD, /*111111111111101*/ // Int64 0x7FFD, /*111111111111101*/ // UInt64 0x5FFD, /*101111111111101*/ // Single 0x5FFD, /*101111111111101*/ // Double 0x5FFD, /*101111111111101*/ // Decimal 0x0003, /*000000000000011*/ // DateTime 0x7FFF, /*111111111111111*/ // String }; // This table represents the safe conversions, i.e. the ones that always succeed. private static Int16[] urtSafeConversionTable = { 0x5FFD, /*101111111111101*/ // Boolean 0x3FE1, /*011111111100001*/ // Char 0x7FFD, /*111111111111101*/ // SByte 0x7FFD, /*111111111111101*/ // Byte 0x7FFD, /*111111111111101*/ // Int16 0x7FFD, /*111111111111101*/ // UInt16 0x7FFD, /*111111111111101*/ // Int32 0x7FFD, /*111111111111101*/ // UInt32 0x7FFD, /*111111111111101*/ // Int64 0x7FFD, /*111111111111101*/ // UInt64 0x5FFD, /*101111111111101*/ // Single 0x5FFD, /*101111111111101*/ // Double 0x5FFD, /*101111111111101*/ // Decimal 0x0003, /*000000000000011*/ // DateTime 0x0001, /*000000000000001*/ // String }; // The index of the type in this table indicates the column/line to lookup for in conversion table. // E.g. SByte is at index 3, means that line 3 and column 3 of conv table represent SByte. private static Type[] urtTypeIndexTable = { typeof(System.Boolean), typeof(System.Char), typeof(System.SByte), typeof(System.Byte), typeof(System.Int16), typeof(System.UInt16), typeof(System.Int32), typeof(System.UInt32), typeof(System.Int64), typeof(System.UInt64), typeof(System.Single), typeof(System.Double), typeof(System.Decimal), typeof(System.DateTime), typeof(System.String) }; // tells if the conversion from sourceUrtType to destinationUrtType is possible at all. internal static bool CanConvert(Type sourceUrtType, Type destinationUrtType) { Int16 lineIndex = -1, columnIndex = -1; for (Int16 i = 0; i < urtTypeIndexTable.Length; i++) { if (sourceUrtType == urtTypeIndexTable[i]) { lineIndex = i; break; } } for (Int16 i = 0; i < urtTypeIndexTable.Length; i++) { if (destinationUrtType == urtTypeIndexTable[i]) { columnIndex = i; break; } } if (lineIndex != -1 && columnIndex != -1) { Int16 tableEntry = urtConversionTable[lineIndex]; Int16 mask = (Int16)(0x4000 >> columnIndex); if ((tableEntry & mask) != 0) { return true; } } return false; } // This method assumes that CanConvert was called first and returned true. internal static string GetConversionMethodName(Type sourceUrtType, Type targetUrtType) { #if DEBUG System.Diagnostics.Debug.Assert(CanConvert(sourceUrtType, targetUrtType), "GetConversionMethodName was called even if cannot convert. Make sure to call CanConvert first."); #endif return "To" + targetUrtType.Name; } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- TransformBlockRequest.cs
- DoubleMinMaxAggregationOperator.cs
- StructureChangedEventArgs.cs
- Transform.cs
- KeyPressEvent.cs
- WorkflowLayouts.cs
- CheckBoxAutomationPeer.cs
- Color.cs
- SchemaHelper.cs
- TextRange.cs
- AddInSegmentDirectoryNotFoundException.cs
- TableLayoutCellPaintEventArgs.cs
- PathGeometry.cs
- PropertyMapper.cs
- RoutedEventConverter.cs
- HttpHandlersInstallComponent.cs
- DataContractSerializerElement.cs
- Parser.cs
- SHA1Managed.cs
- COM2PropertyPageUITypeConverter.cs
- SQLUtility.cs
- Trace.cs
- TreeViewAutomationPeer.cs
- ResourceProperty.cs
- XmlSyndicationContent.cs
- ListCollectionView.cs
- SQLByte.cs
- FontStyles.cs
- Base64Encoder.cs
- HttpCachePolicyBase.cs
- SqlCacheDependencyDatabase.cs
- ClockGroup.cs
- DataRowView.cs
- SurrogateEncoder.cs
- SQLBoolean.cs
- AuthenticationModuleElement.cs
- LicenseContext.cs
- SoapIgnoreAttribute.cs
- RijndaelManaged.cs
- IisTraceWebEventProvider.cs
- MessageEncoderFactory.cs
- CodeCatchClause.cs
- DispatcherObject.cs
- ExpressionPrefixAttribute.cs
- TcpSocketManager.cs
- IdentityHolder.cs
- KeyGesture.cs
- NodeInfo.cs
- SafeEventLogReadHandle.cs
- VirtualStackFrame.cs
- cache.cs
- SiteMapHierarchicalDataSourceView.cs
- Literal.cs
- SafeHGlobalHandleCritical.cs
- ClientFactory.cs
- SchemaType.cs
- NegotiateStream.cs
- Frame.cs
- X509CertificateClaimSet.cs
- TextEditorCopyPaste.cs
- AttachmentCollection.cs
- SecurityPermission.cs
- NGCSerializationManager.cs
- HtmlInputHidden.cs
- InfoCardRSAOAEPKeyExchangeFormatter.cs
- IPAddress.cs
- GeometryConverter.cs
- StartFileNameEditor.cs
- SqlTypesSchemaImporter.cs
- Hashtable.cs
- DataRecord.cs
- MruCache.cs
- ZoneIdentityPermission.cs
- Point3DKeyFrameCollection.cs
- ObjectListFieldCollection.cs
- WebPartConnectionsCancelEventArgs.cs
- TypeUnloadedException.cs
- DelegateSerializationHolder.cs
- BaseAsyncResult.cs
- RegistrationServices.cs
- EmbeddedMailObjectsCollection.cs
- DetailsViewRowCollection.cs
- AutomationPropertyInfo.cs
- HybridDictionary.cs
- Pair.cs
- CqlIdentifiers.cs
- TextPenaltyModule.cs
- BlockCollection.cs
- TextEditorContextMenu.cs
- DataTableTypeConverter.cs
- CodeGeneratorOptions.cs
- Compiler.cs
- XmlCharacterData.cs
- TimeEnumHelper.cs
- KeyboardEventArgs.cs
- ProfilePropertyNameValidator.cs
- RecognizedPhrase.cs
- ViewRendering.cs
- HMAC.cs
- BitmapEffectDrawing.cs