title: Kendo Ui Grid Filterable. How can I change filter operator?
body: <p>Using MVC wrapper, i try to change default filter from "equal" to "contains". I found some examples, but none of them do what I want (or I was wrong to use them...)</p>
  
  <p>Ok, so, this is my code:</p>
  
  <pre><code>@(Html.Kendo().Grid&lt;Portal2.Areas.Coord.Models.ViewModel&gt;()
      .Name("grid")
      .Columns(columns =&gt;
      {
          columns.Bound(c =&gt; c.OperationKey).Hidden();
          columns.Bound(c =&gt; c.Customer).Hidden();
          columns.Bound(c =&gt; c.CarNumber).Filterable(ftb =&gt; ftb.UI("CarFilter"));
          columns.Bound(c =&gt; c.DriverName).Filterable(ftb =&gt; ftb.UI("DriverFilter"));
          columns.Bound(c =&gt; c.PhoneNumber).Filterable(ftb =&gt; ftb.UI("PhoneFilter"));
      })
      .Filterable(f =&gt; f.Extra(false))
  
      .DataSource(dataSource =&gt; dataSource
          .Ajax()
          .Read(r =&gt; r
              .Action("Read", "Operations2", new { startTime = (DateTime)ViewBag.startTime, endTime = (DateTime)ViewBag.endTime })
              )
          .PageSize(20)
          .ServerOperation(false)
          )
      .HtmlAttributes(new { style = "height: 740px" })
      .Scrollable()
      .Groupable()
      .Sortable()
  
      .Pageable(pageable =&gt; pageable
          .Refresh(true)
          .PageSizes(true)
          .ButtonCount(10)
          )
  )
  </code></pre>
  
  <p>I have js functions:</p>
  
  <pre><code>function Filter(element, atr) {
      var entityGrid = $(".k-grid").data("kendoGrid");
      var data = entityGrid.dataSource.data();
      var totalNumber = data.length;
      var drivers = [];
      for (var i = 0; i &lt; totalNumber; i++) {
          var currentDataItem = data[i][atr];
          if ($.inArray(currentDataItem, drivers) == -1)
              drivers.push(currentDataItem);
      }
      element.kendoAutoComplete({
          dataSource: drivers
      });
  }
  
  function CarFilter(element) {
      Filter(element, "CarNumber")
  }
  function DriverFilter(element) {
      Filter(element, "DriverName")
  }
  function PhoneFilter(element) {
      Filter(element, "PhoneNumber")
  </code></pre>
  
  <p>They put all values to helper textbox in each filter. I try this:</p>
  
  <pre><code>    columns.Bound(c =&gt; c.CarNumber)
          .Filterable(ftb =&gt; ftb.UI("CarFilter"))
          .Filterable(ftb =&gt; ftb.Cell(c =&gt; c.Operator("contains")));
  </code></pre>
  
  <p>but thats work only for <code>.Filterable(f =&gt; f.Mode(GridFilterMode.Row))</code></p>
  
  <pre><code>    .Filterable(filterable =&gt; filterable
          .Extra(false)
          .Operators(operators =&gt; operators
              .ForString(str =&gt; str.Clear()
                  .StartsWith("Starts with")
                  .IsEqualTo("Is equal to")
                  .IsNotEqualTo("Is not equal to")
              )
          )
      )  
  </code></pre>
  
  <p>It doesn't provide the expected result.</p>
  
  <p>Suggestions on how to fix this? </p>