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Code Highlighting Breaks when Scrolling


Product Version 2021.1.223
Product RadSyntaxEditor for WPF


The code highlighting is incorrect when scrolling the RadSyntaxEditor control horizontally.


If the width of a given line is longer than that of the viewport of the RadSyntaxEditor control, by default, only the portion of the line which is in the viewport will be processed by the taggers of the control.

This can lead to incorrect highlighting in some cases as can be observed on Figure 1.

Figure 1: Incorrect XAML highlighting

Incorrect highlighting

If you want to ensure that highlighting is correct in all scenarios, you need to set the ShouldTaggersProcessEntireLines property to True.

Example 1: Make RadSyntaxEditor process the entire lines

<telerik:RadSyntaxEditor ShouldTaggersProcessEntireLines="True" /> 

Figure 2: Correct XAML highlighting

Correct XAML highlighting

See Also

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