在Postback之后运行javascript函数

protected void Button1_Click(object sender, EventArgs e)
{
    // 在服务器端处理按钮点击事件
    // ...

    // 注册JavaScript代码
    ClientScriptManager cs = Page.ClientScript;
    string script = "alert('Hello, World!');";
    cs.RegisterStartupScript(this.GetType(), "MyScript", script, true);
}

protected void Button1_Click(object sender, EventArgs e)
{
    // 在服务器端处理按钮点击事件
    // ...

    // 注册JavaScript代码
    ScriptManager.RegisterStartupScript(this, this.GetType(), "MyScript", "alert('Hello, World!');", true);
}

<asp:Button ID="Button1" runat="server" Text="Click me" OnClick="Button1_Click" OnClientClick="alert('Hello, World!');" />