突出显示所有搜索的单词

Question

在我RichtextBox,如果我写的如下.

这是我的笔,
他的笔是美丽的.

现在我搜索单词"is"然后输出如下.

应突出显示所有"是".

Answer 1

关于什么:

static class Utility {
    public static void HighlightText(this RichTextBox myRtb, string word, Color color) {  

       if (word == string.Empty)
            return;

       int s_start = myRtb.SelectionStart, startIndex = 0, index;

       while((index = myRtb.Text.IndexOf(word, startIndex)) != -1) {
           myRtb.Select(index, word.Length);
           myRtb.SelectionColor = color;

           startIndex = index + word.Length;
       }

       myRtb.SelectionStart = s_start;
       myRtb.SelectionLength = 0;
       myRtb.SelectionColor = Color.Black;
    }
}