Setting the Operators

The Filter provides options for defining which filter operators will be displayed in the filtering drop-down by using the .Operators() option.

The following example demonstrates how to set the equals and contains filter operators to the string fields and the greater than and less than filter operators to the numerical fields.

Razor

<script type="text/x-kendo-template" id="itemTemplate">
    <li>
        <strong>#= Name #</strong>, aged #= Age #, is on vacation: #= IsOnLeave #
    </li>
</script>

@(Html.Kendo().DataSource<SampleData>()
    .Name("dataSource1")
    .Ajax(d=>d.Read(r => r.Action("GetPeople", "Filter")))
)

@(Html.Kendo().Filter<SampleData>()
    .Name("filter")

    .Operators(o => // Define the custom texts for the operator names and the available operators.
    {
        o.String(s =>
        {
            s.Eq("Is Exactly");
            s.Contains("Partially Matches");
        });
        o.Number(n =>
        {
            n.Gte("Older Than");
            n.Lt("Younger Than");
        });
    })

    .MainLogic(FilterCompositionLogicalOperator.And)
    .ExpressionPreview() // Shows a text preview of the filter expression.
    .ApplyButton() // Shows the built-in Apply button.
    .Fields(f => // Defining the fields is not mandatory. Otherwise, they will be taken from the data source schema.
                    // If you define the fields, their names and types must match the data source definition.
    {
        f.Add(p=>p.Name).Label("Name");
        f.Add(p=>p.Age).Label("Age");
        f.Add(p=>p.IsOnLeave).Label("On Vacation");
    })
    .FilterExpression(f => { // Defining an initial filter expression is not required.
        f.Add(p => p.Age).IsGreaterThanOrEqualTo(30);
        f.Add(p => p.Name).Contains("Doe");
    })
    .DataSource("dataSource1")
)

@(Html.Kendo().ListView<SampleData>()
    .Name("listView")
    .TagName("ul")
    .DataSource("dataSource1")
    .ClientTemplateId("itemTemplate")
)

<script>
    $(document).ready(function () {
        // Apply filtering immediately after the helper initialization because an initial filter is set.
        $("#filter").getKendoFilter().applyFilter();
    });
</script>

C#

using Kendo.Mvc.Extensions;
using Kendo.Mvc.UI;

public class FilterController : Controller
{
    public ActionResult GetPeople([DataSourceRequest]DataSourceRequest request)
    {
        var people = new List<SampleData>() {
             new SampleData()  { Name = "Jane Doe", Age = 25, IsOnLeave = false },
             new SampleData() { Name = "John Doe", Age = 33, IsOnLeave = true },
             new SampleData() { Name = "John Smith", Age = 37, IsOnLeave = true },
             new SampleData() { Name = "Nathan Doe", Age = 42, IsOnLeave = false }
        };
        return Json(people.ToDataSourceResult(request));
    }

    public ActionResult Index()
    {
        return View();
    }
}

C#

public class SampleData
{
    public int Age { get; set; }
    public string Name { get; set; }
    public bool IsOnLeave { get; set; }
}

See Also

• Basic Usage of the Filter HtmlHelper for ASP.NET MVC (Demo)
• Localization of Messages in the Filter HtmlHelper for ASP.NET MVC
• Server-Side API