javascriptはバックグラウンドの値を取ります.

 <script type="text/javascript" language="javascript">

        var testInput;

        <asp:Literal id="literal" runat="server"></asp:Literal>

        alert(testInput);

 </script>　　

 protected void Page_Load(object sender, EventArgs e)

{

    string test = "HelloWorld";



    this.literal.Text = "testInput=\"" + test + "\";";

}