无法从CodeBehind调用JavaScript函数

function myFunction() {
    // 执行一些操作
}

string script = "<script>myFunction();</script>";
Page.ClientScript.RegisterStartupScript(this.GetType(), "CallMyFunction", script);

function callServer() {
    // 使用AJAX向服务器发送请求
    var xhr = new XMLHttpRequest();
    xhr.open("GET", "ServerPage.aspx?param=value", true);
    xhr.onreadystatechange = function() {
        if (xhr.readyState == 4 && xhr.status == 200) {
            // 处理服务器返回的结果
            var result = xhr.responseText;
            // 执行一些操作
        }
    };
    xhr.send();
}

protected void Page_Load(object sender, EventArgs e)
{
    if (Request.QueryString["param"] != null)
    {
        string paramValue = Request.QueryString["param"];
        // 处理请求并返回结果
        Response.Write("result");
        Response.End();
    }
}

string script = "<script>myFunction();</script>";
ClientScript.RegisterStartupScript(this.GetType(), "CallMyFunction", script);