Problem while calling javascript function on pageload

Question

Dear all,

               i have created a javascript function correctinput() and calling the same in asp .net content page on page load event.

              below is javascript function code

               

<script type="text/javascript">

function correctinput()

{

var trainingid = prompt("Please Enter Training Id Provided to you", " ");

window.location.href = 'Feedback.aspx?Trainingid=' + trainingid;

}

</script>

and code behind is

protected void Page_Load(object sender, EventArgs e)

{

ClientScript.RegisterStartupScript(GetType(), "Javascript", "javascript:correctinput(); ", true);

}

but still function is not being called

please help me