Answers

• allan Posts: 63,360Questions: 1Answers: 10,448 Site admin

  July 2015

  Can you link to the page so I can debug it please? I presume the String.format("{{'DataSource': '{0}' }}", _dbId) stuff just resolves to a simple string, Or is it a JSON string or something else? It might be that you need to use ajax.data as a function to add data to the object that DataTables sends.

  Allan
• JGiunta Posts: 3Questions: 1Answers: 0

  July 2015

  Yes what I am passing into ajax.data is just resolves to "{ 'DataSource': '46' }". In this case the page method is expecting one argument. Just for simplicity the page method is:

  Yes what I am passing into ajax.data is just resolves to "{ 'DataSource': '46' }".  In this case the page method is expecting one argument.  In fact for my playing around with this I an not actual using the DataSource argument, I'm just trying to pass something in to see if I can get it working.  The real method will take a number of different parameters.
  
  For simplicity the page method is:
  
      [WebMethod(EnableSession = true)]
      [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
      public static List<EmployeSummary> GetEmployeSummaryAlt(String DataSource) {
  
              List<EmployeSummary> empRecs = new List<EmployeSummary>();
              empRecs.Add(new EmployeSummary(" Name 1", "01", "ABC", new DateTime()));
              empRecs.Add(new EmployeSummary(" Name 2", "02", "DEF", new DateTime()));
              empRecs.Add(new EmployeSummary(" Name 3", "03", "GHI", new DateTime()));
              return empRecs;
      }
  

  I get back an EmployeSummary object filled in.

  Stepping through jquery.dataTables.js I found that I had ajax.data up to a point and then it was gone. I think I tracked it down to around line 2275. Specifically when data is set to either newData or the $.extended data. That IF returns and empty object with no useful properties. So the $.extend() is not doing what it should be doing correctly. I haven't futzed around with jQuery in quite some time an I need to re-familiarize myself with what exactly $.extend() does.

  I "fixed" it by just adding a line underneath that says data = newData, but I realize I probably messed something else up with this hack.

  From jquery.dataTables.js around line 2275:

      if ($.isPlainObject(ajax) && ajax.data) {
          ajaxData = ajax.data;
  
          var newData = $.isFunction(ajaxData) ?
              ajaxData(data, oSettings) :  // fn can manipulate data or return
              ajaxData;                      // an object object or array to merge
  
          // If the function returned something, use that alone
          
          // -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
          //--> At this point ajaxData and newData = "{ 'DataSource': '46' }" 
          //      which is what I want.
          //--> Below $.isFunction evaluates to FALSE. 
          //      newData evaluates to True, so I fall into the ELSE path.
          // --> the $.extend ends up being:
              -       $.extend(true, data, newData);  {...}   Object
                  +       [Methods]   {...}   
                  +       [prototype] {...}   Object
          // -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
          
          data = $.isFunction(ajaxData) && newData ?
              newData :
              $.extend(true, data, newData); 
  
          data = newData; //<-- My hacky "fix".  
          //--> I need data to contain the arguments
          //      that are passed to the page method.
  
          // Remove the data property as we've resolved it already and don't want
          // jQuery to do it again (it is restored at the end of the function)
          delete ajax.data;
      }
  
      var baseAjax = {
              "data": data, //<-- Without my change 'data' is nothing  useful
                            //     and I get the parameter count exception.
              "success": function (json) {
                  var error = json.error || json.sError;
                  if (error) {
                      _fnLog(oSettings, 0, error);
                  }
  
                  oSettings.json = json;
                  callback(json);
              },
              "dataType": "json",
              "cache": false,
              "type": oSettings.sServerMethod,
              "error": function (xhr, error, thrown) {
                  var ret = _fnCallbackFire(oSettings, null, 'xhr', [oSettings, null, oSettings.jqXHR]);
  
                  if ($.inArray(true, ret) === -1) {
                      if (error == "parsererror") {
                          _fnLog(oSettings, 0, 'Invalid JSON response', 1);
                      }
                      else if (xhr.readyState === 4) {
                          _fnLog(oSettings, 0, 'Ajax error', 7);
                      }
                  }
  
                  _fnProcessingDisplay(oSettings, false);
              }
          };
  
• JGiunta Posts: 3Questions: 1Answers: 0

  July 2015

  If I change my ajax.data property to a function it works. Still don't understand why the $.extend is not merging the two objects properly though.

      oTable = $('#tblEmployeSummary').DataTable({
          "processing": false
          , "serverSide": false
          , "jQueryUI": true
          , "ordering": false
          , "paging": false
          , "scrollCollapse": true
          , "scrollY": '200px'
          , "scrollX": '100%'
          , "ajax": ({
              "type": 'POST'
              , "url": 'ExpBudgetEmploye.aspx/GetEmployeSummaryAlt'
              , "contentType": 'application/json;'
              //, "data": String.format("{{'DataSource': '{0}' }}", _dbId) //--> Will not work
              , "data": function () { return String.format("{{'DataSource': '{0}' }}", _dbId); } 
                 // above works fine.
              , 'dataSrc': 'd'
          })
          , 'columns': [
              { "title": "EmpName", "data": "EmpName", "type": "string", "className": "EmpName" }
              , { "title": "EmpNumber", "data": "EmpNumber", "type": "string", "className": "EmpNumber" }
              , { "title": "JobCode", "data": "JobCode", "type": "string", "className": "JobCode" }
              , { "title": "HireDate", "data": "HireDate", "type": "date", "className": "HireDate" }
          ]
      });
  
  
• allan Posts: 63,360Questions: 1Answers: 10,448 Site admin

  August 2015

  Because $.extend expects an object, but it looks like you are giving it a string. If you added JSON.parse( ... ) to get an object from your string it would probably work.

  Allan