C#用richTextBox1控件实现实时搜索功能,并提示

1. private int currentIndex = 0;
2. private string searchKey;
3. private bool isFound = false;
4. private void button4_Click(object sender, EventArgs e)
5. {
6. searchKey = textBox2.Text.Trim();
7. if (searchKey == "")
8. {
9.  
10. MessageBox.Show("^0^ 搞什么呀？不管您是帅锅还是美女都应该输入要查找的关键字吧？", "^0^^0^^0^", MessageBoxButtons.OK, MessageBoxIcon.Warning);
11. return;
12. }
13. currentIndex = richTextBox1.Find(searchKey, currentIndex, RichTextBoxFinds.None);
14.  
15. if (currentIndex == -1)
16. {
17. if (isFound)//表示如果曾经找到过
18. {
19.  
20. MessageBox.Show("已经搜索到文件最底部！", "提示：", MessageBoxButtons.OK, MessageBoxIcon.Warning);
21.  
22. }
23. else
24. {
25. MessageBox.Show("没有搜索到关于[" + searchKey + "]的任何内容！", "提示：", MessageBoxButtons.OK, MessageBoxIcon.Warning);
26.  
27. }
28. currentIndex = 0;//重置索引
29. isFound = false; //重置标志位
30. }
31. else
32. {
33. this.richTextBox1.Select(currentIndex, searchKey.Length);
34. currentIndex += searchKey.Length;
35. isFound = true;
36. }
37. }