我想在读入的文本文件中找到上海的电话号码



void MenuLoadClick(object sender, System.EventArgs e)
{
OpenFileDialog dlgOpenFile=new OpenFileDialog();
dlgOpenFile.Title="open";
dlgOpenFile.Filter="open(*.html)|*.html|All Files(*.*)|*.*";
if(dlgOpenFile.ShowDialog()==DialogResult.OK)
{
fileName=dlgOpenFile.FileName;
FileStream aFile=new FileStream(fileName,FileMode.Open);
StreamReader sr=new StreamReader(aFile);
this.textBox1.Clear();
this.textBox1.Text=sr.ReadToEnd();

Regex re= new Regex(@"^\(\d{3}\) \d{3}－\d{8}$');

下面该怎么样写？？？
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