i am using asp.net web forms and i am using bassistance.de jquery validation.. i have bunch of fields in the form and its validatating how it suppose to but its still executing my code behind code, why is it doing that?

here is my code:

form:

   <script type="text/javascript"> 

 $(document).ready(function() {    

            $("#aspnetForm").validate({
                rules: 
                {
                    <%=txtVisitName.UniqueID %>: 
                    {
                        maxlength:1,
                        //minlength: 12,
                        required: true
                    }
                  .................
                },   
                messages: 
                    {
                        <%=txtVisitName.UniqueID %>:
                        { 
                            required: "Enter visit name", 
                            minlength: jQuery.format("Enter at least {0} characters.") 
                        }
                        ............

                     }, 

            success: function(label) { 

   label.html("&nbsp;").addClass("checked");
  }

  }); 

             $("#aspnetForm").validate();  
        });
            </script>

<div >

        <h1>
  Page</h1>
        <asp:Label runat="server" ID='Label1'>Visit Name:</asp:Label>
        <asp:TextBox ID="txtVisitName" runat='server'></asp:TextBox>
        ............
        ...............

       <button id="btnSubmit" name="btnSubmit" type="submit"> Submit</button>

    </div> 

and i have a external .js file referencing to my web form page.

$(document).ready(function() 
{
    $("#btnSubmit").click(function() {
            SavePage();
        });
});

i have a WebMethod .cs and i have bookmark and it does hitting that line of code even thoug my page is in invalid state.

how would i fix this?

thanks.