Sorting jqGrid in ASP.NET MVC client view with jQuery and LINQ-to-Entities

Question

I'm a jQuery noob, so I'm sure I'm missing something simple here.

I've got the jqGrid working with an action that creates JSON data from a LINQ-to-Entities operation. But when I click on the column headers in the browser, the rows don't sort. The ascending/descending indicator shows up, but nothing else happens.

The necessary JavaScript and CSS links are in the master page header:

<script src="/Scripts/jquery-1.3.2.min.js" type="text/javascript"></script>
<!-- CSS and JavaScript files for jqGrid to display on Details pages -->
<link rel="stylesheet" type="text/css" href="/scripts/jQuery/jqGrid-3.4.4/themes/green/grid.css" title="green" media="screen" />
<script src="/Scripts/jQuery/jqGrid-3.4.4/jquery.jqGrid.js" type="text/javascript"></script>
<script src="/Scripts/jQuery/jqGrid-3.4.4/js/jqModal.js" type="text/javascript"></script>
<script src="/Scripts/jQuery/jqGrid-3.4.4/js/jqDnR.js" type="text/javascript"></script>

Here's my initialization code:

// jqGrid setup.
$("#gridlist").jqGrid({
    url: '/Contact/GridData',
    datatype: 'json',
    mtype: 'GET',
    colNames: ['ID', 'First Name', 'Last Name', 'Organization'],
    colModel: [
        { name: 'id', index: 'id', width: 40, align: 'left', resizable: true },
        { name: 'first_name', index: 'first_name', width: 200, align: 'left', resizable: true, sortable: true, sorttype: "text" },
        { name: 'last_name', index: 'last_name', width: 200, align: 'left', resizable: true, sortable: true, sorttype: "text" },
        { name: 'organization', index: 'organization', width: 300, align: 'left', resizable: true, sortable: true, sorttype: "text"}],
    pager: jQuery('#pager'),
    rowNum: 5,
    rowList: [5, 10, 20, 50],
    repeatitems: false,
    viewrecords: true,
    imgpath: '/scripts/jQuery/jqGrid-3.4.4/themes/green/images',
    caption: 'Contacts'
});                  

And here's the HTML:

    <h3>My Grid Data</h3>
    <table id="gridlist" class="scroll" cellpadding="0" cellspacing="0">
    </table>
    <div id="pager" class="scroll" style="text-align:center;">
    </div>

And, just for completeness, the action method:

public ActionResult GridData()
{
    var page = new { page = 1 };

    IEnumerable contacts = _db.ContactSet;
    int i = 0;
    var rows = new object[contacts.Count()];

    foreach (Contact contact in contacts)
    {
        rows[i] = new { id = contact.ID, cell = new[] { contact.ID.ToString(), contact.First_Name, contact.Last_Name, contact.Organization } };
        i++;
    }

    var result = new JsonResult();
    result.Data = new { page = 1, records = 2, rows, total = 1 };

    return result;
}

Any ideas what obvious setting I'm missing here?

Answer 1

There are two basic ways to handle this. The grid can sort the data itself. I can't remember how to turn this on, because I never use this option. Generally, I work with datasets which are too large to return to the page, so I use the grid's paging features. This requires doing this sort on the server, since the grid will not see the entire dataset.

To do the paging on the server, add a sidx and a sord (both strings) argument to your action. sidx will be the name of the column to sort on. sord will be the direction, asc or desc.

I have a demo project which shows how to do this (using LINQ to Objects). But using LINQ to Entities is almost identical; I use LINQ to Entities in my production/non-demo code. Download the demo solution and look for yourself.

Answer 2

I tried to make Craig's method work with my data, but with the same results I had with Phil Haack's method: the grid is always empty, no matter what I do. I get client-side errors like

The query syntax is not valid., near keyword 'ASC', line 6, column 2.

I've already wasted too much time on this, so I'm just going to have to remove jqGrid and roll my own paging and sorting.

Thanks anyway...

Answer 3

  I think below example should do it. 2 important points make sure your sort column has "it" keyword as prefix. (thats for linq to know). second you load only the number of objects array element as the rows the query can read.

  var context = new HaackOverflowDataContext();

    int pageIndex = Convert.ToInt32(page) - 1;
    int pageSize = rows;
    int totalRecords = context.Question.Count();
    int totalPages = (int)Math.Ceiling((float)totalRecords / (float)pageSize);

    var questions = context.Question.OrderBy("it."+ sidx + " " + sord).Skip(pageIndex * pageSize).Take(pageSize);

    int i = 0;
    var rowsObj = new object[pageSize>totalRecords ?  totalRecords : pageSize];

    foreach (Question q in questions)
    {
        rowsObj[i] = new { id = q.Id, cell = new object[] { q.Id, q.Votes, q.Title } };
        i++;
    }

    var result = new JsonResult();
    result.Data = new
    {
        total = totalPages,
        page = page,
        records = totalRecords,
        rows = rowsObj
    };

    return result;

Thanks Anuj Pandey www.anuj.co.in

he he ... does this mean i know programming :)

Answer 4

OK, I should have posted this when I figured it out, but I ended up getting caught up in other tasks. Here is what I did that worked with LINQ to Entities, implemented for a report entity. First, the code to load the jqGrid with a default search was simple (once I figured out what I had missed):

$(document).ready(function() {

    // Set up jqGrid for the report search results table.
    // This is displayed in a tab in the bottom section of the master page.
    $("#searchResultList").jqGrid({
        url: '/Report/GetResultsL2E/',
        datatype: 'json',
        mtype: 'GET',
        colNames: ['', 'ID', 'Title', 'Post_Date', 'Start_Date', 'End_Date', 'Summary'],
        colModel: [
          { name: 'act', index: 'act', width: 75, sortable: false },
          { name: 'ID', index: 'ID', width: 40, align: 'left', hidden: true },
          { name: 'Title', index: 'Title', width: 150, align: 'left' },
          { name: 'Post_Date', index: 'Post_Date', width: 80, align: 'left', formatter: 'date' },
          { name: 'Start_Date', index: 'Start_Date', width: 80, align: 'left', formatter: 'date' },
          { name: 'End_Date', index: 'End_Date', width: 80, align: 'left', formatter: 'date' },
          { name: 'Summary', index: 'Summary', width: 240, align: 'left' }
        ],
        pager: jQuery('#searchResultPager'),
        rowNum: 10,
        rowList: [5, 10, 20, 50],
        sortname: 'Title',
        sortorder: "asc",
        viewrecords: true,
        imgpath: '/Scripts/jqGrid/themes/green/images',
        caption: 'Report Search Results', 
        editurl: "/Report/Edit",
        scroll: true,
        height: 'auto',
        recordtext: ' Reports',
        pgtext: ' of ',
        multiselect: true, 
        multiboxonly: true, //adds check box column
        altRows: true,
        loadComplete: function() {
            var ids = jQuery("#searchResultList").getDataIDs();
            for (var i = 0; i ";
                se = "";
                ce = "";
                jQuery("#searchResultList").setRowData(ids[i], { act: be + se + ce })
            }
        }
    }).navGrid('#searchResultPager',
    { edit: false, add: false, del: false, search: false }, //options 
    {height: 280, reloadAfterSubmit: false }, // edit options 
    {height: 280, reloadAfterSubmit: false }, // add options 
    {reloadAfterSubmit: false }, // del options 
    {} // search options 
    );
});

The method to load the default search set returns the first page of the total set of reports available:

/// 
/// Query the ReportSet to return a paged, sorted set of Report entity properties in response to a call from a view.
/// 
/// The name of the column to use for sorting.
/// The order of the sort (ascending or descending).
/// The number of the page to return to the calling process.
/// The number of rows to return for the page.
/// This ActionResult returns a JSON result to be used by a jqGrid using the jQuery library.
/// jQuery requires a script tag linking the jQuery.js script.
/// jqGrid requires stylesheet links to the following scripts and stylesheets:
/// 
/// jQuery/themes/base/ui.all.css
/// jqGrid/themes/green/grid.css (or other theme CSS file)
/// jqGrid/jquery.jqGrid.js
/// jqGrid/grid.base.js
/// jqGrid/js/jqModal.js
/// jqGrid/js/jqDnR.js
/// 
public ActionResult GetResultsL2E(string sidx, string sord, int page, int rows)
{
    int pageIndex = Convert.ToInt32(page) - 1;
    int pageSize = rows;
    int totalRecords = _db.ReportSet.Count();
    int totalPages = (int)Math.Ceiling((float)totalRecords / (float)pageSize);
    int startRecord = pageIndex * pageSize;

    List rowStrings = new List();
    // Get all of the reports in the model in a fixed order (for comparison).
    //var reports = from item in _db.ReportSet
    //              orderby item.Start_Date, item.Title
    //              select new { item.ID, item.Title, item.Post_Date, 
    //              item.Start_Date, item.End_Date, item.Summary };
    // Get all of the reports in the model in a dynamic order passed from jqGrid.
    string orderBytext = "";
    orderBytext = string.Format("it.{0} {1}", sidx, sord);
    var reports = _db.ReportSet
                   .OrderBy(orderBytext);

    List stringList = new List();

    int counter = reports.Count();
    foreach (var report in reports)
    {
        var rowString = new
        {
            id = report.ID,
            cell = new[] {
                    "",
                    report.ID.ToString(),
                    report.Title,
                    report.Post_Date.ToShortDateString(),
                    report.Start_Date.ToShortDateString(),
                    report.End_Date.ToString(),
                    report.Summary.ToString()}
        };
        stringList.Add(rowString);
    }

    var rowsOut = new object[counter];
    for (int i = 0; i 

I later added another method to respond to the user selecting columns to sort, using the PredicateBuilder discussed from the Albaharis' book C# in a Nutshell's section on Dynamically Composing Expression Predicates. I discussed my solution to that in a question I started on MSDN at PredicateBuilder fails on nested predicates with LINQ to Entities

Answer 5

Try the example given in this post,

http://arahuman.blogspot.com/2009/06/jqgrid-using-mvc-json-and-datatable.html

Answer 6

I had the same problem where the jqGrid frame was showing up but the rows were not. My solution was to add the following code.

**jsonData.JsonRequestBehavior = JsonRequestBehavior.AllowGet;**
         return jsonData;