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Blazor Grid Filtering Overview

The Grid component offers built-in support for filtering.


To enable filtering, set the grid's FilterMode property to one of the following values:

The behavior of the filter input and the available filter operators will depend on the column data type. For example, a boolean field will only have the options "is true" and "is false" and will not have operators like "contains" or "greater than".

You can filter more than one column at a time, and all filter rules will be applied together with an AND logic.

You can prevent the user from filtering a certain field by setting Filterable="false" on its column.

More Filtering Options

In addition to the two main filtering modes, the grid offers two more features that can enhance the user experience when looking for data:

  • A searchbox in the toolbar can amend the filters and let the user look up many fields at once

  • The filter menu can show a list of checkboxes with the distinct values from the data to make filtering resemble Excel.

Filter Descriptors

The Grid filter state is stored in CompositeFilterDescriptors. The below information is important if you want to get or change the Grid filters programmatically.

Each CompositeFilterDescriptor contains a collection of FilterDescriptors. All descriptors in the collection are applied with an AND or an OR LogicalOperator.

  • Filter Row - each CompositeFilterDescriptor targets a specific field. By default, one filter can be applied to a field using the Filter Row operator. The filter value is stored in the first FilterDescriptor instance of the CompositeFilterDescriptor for that field.

  • Filter Menu - each CompositeFilterDescriptor targets a specific field. Filter values from the separate filter opearators in the menu are stored in different FilterDescriptor instances of the dedicated CompositeFilterDescriptor for that field.

  • SearchBox - one CompositeFilterDescriptor is created in the state when the user types in the Searchbox. By default, it targets all string fields. A dedicated FilterDescriptor instance is added to this CompositeFilterDescriptor for each string field. Each FilterDescriptor instance contains the filter value typed in the Searchbox.

Custom Filtering

There are two approaches to customize the grid filtering behavior, and you can use them together:

  • Perform the data operations yourself (e.g., by outsourcing them to some API backend or other service) - to do that, use the OnRead event. This will let you fetch only the current page of data for the grid, instead of pulling the entire data set and storing it in-memory in the view-model.

  • Customize the appearance and behavior of the filters - for that, use the Filter Templates the grid provides.

Customize The Filter Editors

You can customize the filter editors declaratively for some data types. It is possible to change the editor component or the editor format.

GridColumn Parameter Type Works for Description
FilterEditorType GridFilterEditorType enum DateTime columns The component, which the Grid will render for filtering (DatePicker or DateTimePicker).
FilterEditorFormat string DateTime and numeric columns The Format of the filtering component. Do not use a placeholder (e.g. set "D", not "{0:D}").
@* Using FilterEditorType and FilterEditorFormat parameters *@

<TelerikGrid Data=@GridData 
        <GridColumn Field="@nameof(Employee.Name)" />
        <GridColumn Field="@nameof(Employee.AgeInYears)" Title="Age" />
        <GridColumn Field="@nameof(Employee.HireDate)" 
                    FilterEditorFormat="yyyy-MM-dd HH:mm"
                    Title="Hire Date" />
        <GridColumn Field="@nameof(Employee.IsOnLeave)" Title="On Vacation" />

@code {
    public List<Employee> GridData { get; set; }

    protected override void OnInitialized()
        GridData = new List<Employee>();
        var rand = new Random();
        for (int i = 0; i < 100; i++)
            GridData.Add(new Employee()
                EmployeeId = i,
                Name = "Employee " + i.ToString(),
                AgeInYears = rand.Next(10, 80),
                HireDate = DateTime.Now.Date.AddDays(rand.Next(-20, 20)),
                IsOnLeave = i % 3 == 0

    public class Employee
        public int? EmployeeId { get; set; }
        public string Name { get; set; }
        public int? AgeInYears { get; set; }
        public DateTime HireDate { get; set; }
        public bool IsOnLeave { get; set; }

Advanced Examples

The following articles and sample projects can be helpful when implementing filtering:


  • The grid uses Activator.CreateInstance<TItem>(); to get the type of the item it is bound to in order to generate proper filters and filter operators for them. Thus, the Model should have a Parameterless constructor defined.

See Also

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