1、UpdatePanel 使用中

protected void Button1_Click(object sender, EventArgs e)
{
this.Label1.Text = "测试时间：" + DateTime.Now.ToString();

ScriptManager.RegisterStartupScript(UpdatePanel1, UpdatePanel1.GetType(),"testalert", "<script>Test();</script>", false);
}

2、UpdatePanel 没有使用

protected void Button1_Click(object sender, EventArgs e)
{
    this.Label1.Text = "测试时间：" + DateTime.Now.ToString();
    ClientScriptManager cs = this.ClientScript;
    cs.RegisterStartupScript(this.GetType(), "HelloWorld", "<script>alert(‘test alert‘);</script>");
}

ASPX 后台调用前台Js