How to Return DataTable from WebMethod using JSON and JQuery in asp.net?

Here is how I normally do it. I load the DataTable contents into a dictionary, serialize it and everything works. You can modify the code to suit your needs.

[WebMethod]public string GetQueryInfo(){    String daresult = null;    DataTable yourDatable = new DataTable();    DataSet ds = new DataSet();    ds.Tables.Add(yourDataTable);    daresult = DataSetToJSON(ds);    return daresult;}public string DataSetToJSON(DataSet ds){    Dictionary < string, object > dict = new Dictionary<string, object>();    foreach(DataTable dt in ds.Tables) {        object[] arr = new object[dt.Rows.Count + 1];        for (int i = 0; i <= dt.Rows.Count - 1; i++) {            arr[i] = dt.Rows[i].ItemArray;        }        dict.Add(dt.TableName, arr);    }    JavaScriptSerializer json = new JavaScriptSerializer();    return json.Serialize(dict);}

On your aspx.

$.ajax({    type: "POST",    url: 'Webservices/GetQueryInfo',    data: {},    contentType: "application/json; charset=utf-8",    dataType: 'json',    success: function (data) {        var objdata = $.parseJSON(data.d);        // now iterate through this object's contents and load your gridview    }});

There are many tutorials on how to load a grid view using JavaScript or jquery. This will at least give you a starting point. You can find a nice example here.To do CRUD operations with the GridView see link here