TextSource Class
Provides an abstract class for specifying character data and formatting properties to be used by the TextFormatter object.
Assembly: PresentationCore (in PresentationCore.dll)
The TextSource type exposes the following members.
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Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
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Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
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GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
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GetPrecedingText | Retrieves the text span immediately before the specified TextSource position. |
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GetTextEffectCharacterIndexFromTextSourceCharacterIndex | Retrieves a value that maps a TextSource character index to a TextEffect character index. |
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GetTextRun | Retrieves a TextRun starting at a specified TextSource position. |
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GetType | Gets the Type of the current instance. (Inherited from Object.) |
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MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
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ToString | Returns a string that represents the current object. (Inherited from Object.) |
All access to the text in the TextSource object is through the GetTextRun, which is designed to allow the text layout client to virtualize text in any way it chooses.
TextFormatter is the WPF text engine that provides services for formatting text and breaking text lines. TextFormatter can handle different text character formats and paragraph styles, and includes support for international text layout. Unlike a traditional text API, the TextFormatter interacts with a text layout client through a set of callback methods. It requires the client to provide these methods in an implementation of the TextSource class. The following list describes the three members you must override:
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GetTextRun : Retrieves a TextRun starting at a specified TextSource position.
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GetPrecedingText : Retrieves the text span immediately before the specified TextSource position.
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GetTextEffectCharacterIndexFromTextSourceCharacterIndex : Retrieves a value that maps a TextSource character index to a TextEffect character index.
Note
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For a complete code sample that shows how to implement a derived TextSource class, see Advanced Text Formatting Sample . |
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
