c#查询QQ状态是否在线查询代码

private void button3_Click(object sender, System.EventArgs e)
{
if(textBox3.Text=="")
{
MessageBox.Show("必须填写当前的查询的QQ号码!","错误提示!");
textBox3.Focus();
return;
}
else
{
string strQQ=textBox3.Text.Trim();
string strSearchQQ=" http://wpa.qq.com/pa?p=1:"+strQQ+":3";
string strQQStatus=GetWebContent(strSearchQQ).Substring(0,7);
switch(strQQStatus)
{
case "GIF89aK":MessageBox.Show(strQQ+"不在线","QQ状态提示!");
break;
case "GIF89aJ":MessageBox.Show(strQQ+"在线","QQ状态提示!");
break;
}
}
}