以前写过一个web上的查找的例子，这次写了一个winform下的，当然还是要用正则表达式。一个窗口，上面有一个richTextBox，一个输入框，三个button：查找，前一个，后一个。
主要代码：
MatchCollection matches;
int index = 0;
private void button1_Click(object sender, EventArgs e)
{
this.index = 0;
this.richTextBox1.HideSelection = false;
Regex rx = new Regex(this.textBox1.Text,
RegexOptions.Compiled | RegexOptions.IgnoreCase);
matches = rx.Matches(this.richTextBox1.Text);
btnNext_Click(sender, e);
}
private void btnNext_Click(object sender, EventArgs e)
{
if (matches.Count > 0 && index < matches.Count )
{
Match match = matches[index];
int currentPos = match.Index;
this.richTextBox1.Select(currentPos, this.textBox1.Text.Length);
if (index == matches.Count - 1)
{
MessageBox.Show("end");
}
else
{
index += 1;
}
}
}
private void btnPrev_Click(object sender, EventArgs e)
{
if (matches.Count > 0 && index >= 0 )
{
Match match = matches[index];
int currentPos = match.Index;
this.richTextBox1.Select(currentPos, this.textBox1.Text.Length);
if (index == 0)
{
MessageBox.Show("start");
}
else
{
index -=1;
}
}
}