在Outlook.mailItem中突出显示特定的Word.Range

Question

Outlook.Inspector = Globals.ThisAddIn.Application.ActiveInspector();
Word.Document document = (Word.Document)inspector.WordEditor;

//I have some code that determines start and end of the range i want to highlight.
//lets say they are:
object start = 0;
object end = 5;

Word.Range rng = document.Range(ref start, ref end);

//I have tried this but it didn't work but it throws an exception that Highlight 
//section is disabled or something like that.
rng.HighlightColorIndex  = WdColorIndex.wdYellow;

我还尝试从范围中获取文本并使用Word.Find对象并在此文本上使用Find.HitHighlight方法，但问题是它突出显示超出指定范围的文本外观。

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