判断里改就行了  <form id="form1" runat="server">
    <div>        <script>
    function aa()
    {
    var t =document .getElementById ("s");
    var cue=document .getElementById ("cue").value ;
   
       if (confirm(cue)==true) 
                    t.value ="true";
                          else
                             t.value ="false";    }
        </script>        <script runat="server">
    
            protected void Page_Load(object sender, EventArgs e)
            {
                Button1.Attributes.Add("onclick", "aa()");
                cue.Value = "aa";
            }            protected void Button1_Click(object sender, EventArgs e)
            {                if (s.Value == "true")
                {
                    Response.Write("true");
                }
                else
                {
                    Response.Write("f");
                }
            }
        </script>        <input type="hidden" runat="server" id="s" />
        输入要弹出的值:<input type="text" runat="server" id="cue" />
        <asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" />
    </div>
    </form>