Element structure and document object model

The document object model of RadTextBoxControl is represented by LineInfo class and ITextBlock interface. The LineInfo class contains logical information about the start and end block of the line and its size. The ITextBlock interface exposes layout information of a single word. Notice that the elements which implement ITextBlock interface should be inheritors of RadElement.

The visual element structure of the RadTextBoxControlElement is presented on the following diagram:

• TextBoxViewElement represents a viewport that is responsible for the layout and arrangement of all text blocks. It executes layout algorithms for single, multi-line and word wrap layout. It inherits from ITextBlock.

• TextBlockElement represents a single word, which is rendered on the viewport.

Depending on how content of the editor is changed, one or more instances of ITextBlock can be merged into a single instance.

See Also

• Caret positioning and selection
• Creating custom blocks
• AutoComplete
• Properties and Events
• Text editing