Pass parameters to a SQL procedure in .ashx

Question

I have a C# Web Forms application that is displaying a jqGrid on the home page. I struggled with the jqGrid for a while as it was returning the "jqGrid is not a function" error on any page that inherited from site.master.

To solve this, I put the code and script references for the grid in a user control and then referenced the control on the home page:

<%@ Register TagPrefix="My" TagName="GridControl" Src="~/UserControls/Grid.ascx"%> 

<My:GridControl ID ="gridControl" runat="server" />

Inside Grid.ascx I have the code to populate the grid which gets it's data from a stored procedure inside a handler:

    <script type="text/javascript">
    $(function () {
        $("#dataGrid").jqGrid({
            url: 'Handler1.ashx',
            datatype: 'json',

I used the handler along with Newtonsoft JSON.NET to avoid the json string length error.

The stored procedure has 11 parameters which when set to NULL, return all rows, which is what I want for the initial page load.

sqlCmd.Parameters.Add("@ProjNum", SqlDbType.Int).Value = DBNull.Value;

So now, I want to filter the results based on values from dropdowns on Default.aspx. The dropdowns are populated from SQL calls as well. But my question is how to get the values from the dropdowns into my handler?

I know I can do something like url: Handler1.ashx?asgnID=19 where I've just hardcoded the value, and then get it from the context.Request.QueryString, but I still don't know how to pass the value.

I've also read about using session, and I've tried passing a json string in ajax from default.aspx in a java button click event - which didn't work because the handler ends up getting called twice. I'm a little green on this stuff, and was hoping for a better alternative.

Answer 1

In case anyone is having the same issue, I did the following to solve it:

Create a function to extract the parameter from the url.

function GetParameterValues(param) {   
var url = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
for (var i = 0; i < url.length; i++) {   
    var urlparam = url[i].split('=');   
    if (urlparam[0] == param) {   
        return urlparam[1];   
        }   
    }   
}   

Assign the parameter value to a variable and use it in your Jqgrid url:

$(function () {
var id = GetParameterValues('id');
$('#statusGrid').jqGrid({
    url: 'Handler2.ashx?id=' + id.toString(), 
    datatype: 'json',
    mtype: 'POST',

    colNames: ['Status', 'Status Date', 'Status Time',...

And, inside the handler, extract the id from the context in ProcessRequest()

int ProjNum = Convert.ToInt32(context.Request["Id"]);