Code:
/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / Xml / System / Xml / Bits.cs / 1305376 / Bits.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //----------------------------------------------------------------------------- namespace System.Xml { using System; using System.Diagnostics; ////// Contains static utility methods used to manipulate bits in a word. /// internal static class Bits { private static readonly uint MASK_0101010101010101 = 0x55555555; private static readonly uint MASK_0011001100110011 = 0x33333333; private static readonly uint MASK_0000111100001111 = 0x0f0f0f0f; private static readonly uint MASK_0000000011111111 = 0x00ff00ff; private static readonly uint MASK_1111111111111111 = 0x0000ffff; ////// Returns the number of 1 bits in an unsigned integer. Counts bits by divide-and-conquer method, /// first computing 16 2-bit counts, then 8 4-bit counts, then 4 8-bit counts, then 2 16-bit counts, /// and finally 1 32-bit count. /// public static int Count(uint num) { num = (num & MASK_0101010101010101) + ((num >> 1) & MASK_0101010101010101); num = (num & MASK_0011001100110011) + ((num >> 2) & MASK_0011001100110011); num = (num & MASK_0000111100001111) + ((num >> 4) & MASK_0000111100001111); num = (num & MASK_0000000011111111) + ((num >> 8) & MASK_0000000011111111); num = (num & MASK_1111111111111111) + (num >> 16); return (int) num; } ////// Returns true if the unsigned integer has exactly one bit set. /// public static bool ExactlyOne(uint num) { return num != 0 && (num & (num - 1)) == 0; } #if !SILVERLIGHT // These methods are not used in Silverlight ////// Returns true if the unsigned integer has more than one bit set. /// public static bool MoreThanOne(uint num) { return (num & (num - 1)) != 0; } ////// Clear the least significant bit that is set and return the result. /// public static uint ClearLeast(uint num) { return num & (num - 1); } #endif ////// Compute the 1-based position of the least sigificant bit that is set, and return it (return 0 if no bits are set). /// (e.g. 0x1001100 will return 3, since the 3rd bit is set). /// public static int LeastPosition(uint num) { if (num == 0) return 0; return Count(num ^ (num - 1)); } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. //------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //----------------------------------------------------------------------------- namespace System.Xml { using System; using System.Diagnostics; ////// Contains static utility methods used to manipulate bits in a word. /// internal static class Bits { private static readonly uint MASK_0101010101010101 = 0x55555555; private static readonly uint MASK_0011001100110011 = 0x33333333; private static readonly uint MASK_0000111100001111 = 0x0f0f0f0f; private static readonly uint MASK_0000000011111111 = 0x00ff00ff; private static readonly uint MASK_1111111111111111 = 0x0000ffff; ////// Returns the number of 1 bits in an unsigned integer. Counts bits by divide-and-conquer method, /// first computing 16 2-bit counts, then 8 4-bit counts, then 4 8-bit counts, then 2 16-bit counts, /// and finally 1 32-bit count. /// public static int Count(uint num) { num = (num & MASK_0101010101010101) + ((num >> 1) & MASK_0101010101010101); num = (num & MASK_0011001100110011) + ((num >> 2) & MASK_0011001100110011); num = (num & MASK_0000111100001111) + ((num >> 4) & MASK_0000111100001111); num = (num & MASK_0000000011111111) + ((num >> 8) & MASK_0000000011111111); num = (num & MASK_1111111111111111) + (num >> 16); return (int) num; } ////// Returns true if the unsigned integer has exactly one bit set. /// public static bool ExactlyOne(uint num) { return num != 0 && (num & (num - 1)) == 0; } #if !SILVERLIGHT // These methods are not used in Silverlight ////// Returns true if the unsigned integer has more than one bit set. /// public static bool MoreThanOne(uint num) { return (num & (num - 1)) != 0; } ////// Clear the least significant bit that is set and return the result. /// public static uint ClearLeast(uint num) { return num & (num - 1); } #endif ////// Compute the 1-based position of the least sigificant bit that is set, and return it (return 0 if no bits are set). /// (e.g. 0x1001100 will return 3, since the 3rd bit is set). /// public static int LeastPosition(uint num) { if (num == 0) return 0; return Count(num ^ (num - 1)); } } } // 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
- hebrewshape.cs
- StrongNameUtility.cs
- CodeConstructor.cs
- DataBindingExpressionBuilder.cs
- UpDownBase.cs
- SqlDataSource.cs
- TypeFieldSchema.cs
- SecurityHelper.cs
- TableRow.cs
- ExpressionsCollectionConverter.cs
- FrameworkContextData.cs
- CheckPair.cs
- WinCategoryAttribute.cs
- EqualityComparer.cs
- SafeBuffer.cs
- ToolStripOverflow.cs
- DropDownHolder.cs
- TemplateComponentConnector.cs
- DBCSCodePageEncoding.cs
- SqlDataSourceEnumerator.cs
- XmlArrayItemAttribute.cs
- OracleString.cs
- QueryCacheManager.cs
- ActivityTypeResolver.xaml.cs
- TaskFormBase.cs
- XmlWellformedWriter.cs
- OperandQuery.cs
- FormViewDeletedEventArgs.cs
- CalendarTable.cs
- OleDbRowUpdatedEvent.cs
- InteropAutomationProvider.cs
- DesignerAttribute.cs
- ChannelTokenTypeConverter.cs
- OdbcConnectionPoolProviderInfo.cs
- ObjectReaderCompiler.cs
- StringSorter.cs
- HighContrastHelper.cs
- AccessViolationException.cs
- CheckBoxRenderer.cs
- RelationshipEndCollection.cs
- DefaultMemberAttribute.cs
- SQLDoubleStorage.cs
- TypeLibConverter.cs
- ComponentSerializationService.cs
- DuplexChannelFactory.cs
- UnmanagedHandle.cs
- Package.cs
- AccessKeyManager.cs
- DataTableTypeConverter.cs
- ResourcePermissionBaseEntry.cs
- InstallerTypeAttribute.cs
- SapiGrammar.cs
- HttpRequest.cs
- FlowDocumentFormatter.cs
- Pen.cs
- CaseStatementSlot.cs
- MarkupObject.cs
- WaitHandleCannotBeOpenedException.cs
- SecurityStateEncoder.cs
- WebPartCloseVerb.cs
- DashStyles.cs
- FlowDocumentFormatter.cs
- RectangleGeometry.cs
- ConstructorBuilder.cs
- SectionInput.cs
- MetadataItemEmitter.cs
- OdbcCommand.cs
- AssemblyUtil.cs
- TogglePattern.cs
- OdbcConnectionFactory.cs
- ReaderOutput.cs
- BrowserCapabilitiesCodeGenerator.cs
- ValidationError.cs
- PostBackOptions.cs
- CustomAttributeBuilder.cs
- MultipleViewProviderWrapper.cs
- ConfigXmlElement.cs
- DbgCompiler.cs
- TableColumn.cs
- AlignmentXValidation.cs
- COM2Enum.cs
- GridView.cs
- TextDecoration.cs
- CodeExpressionStatement.cs
- HandlerBase.cs
- HandledEventArgs.cs
- ColumnCollection.cs
- PolyBezierSegment.cs
- TCPClient.cs
- ParentQuery.cs
- WebControlAdapter.cs
- QueryOptionExpression.cs
- LinearQuaternionKeyFrame.cs
- DataGridViewColumnDividerDoubleClickEventArgs.cs
- InvalidAsynchronousStateException.cs
- RequestCachePolicyConverter.cs
- TableLayoutPanelBehavior.cs
- UriTemplateTrieNode.cs
- QueryOperationResponseOfT.cs
- SerializerWriterEventHandlers.cs