Sorting Overview

This article describes the sorting functionality in RadGrid and provides a quick overview of the ways to customize the sorting.

To see the sorting in action, see the Sorting Demo.

You can configure RadGrid to automatically sort its columns by setting the AllowSorting property to True. When sorting is enabled, arrow buttons appear on the column headers and allow users to select a sorting mode for each column. There are three sorting modes:

• Ascending

• Descending

• No Sort

You can configure the grid to allow sorting by more than one DataField (called multi-column sorting).

Culture Dependency of the Sorting Algorithms

The sorting functionality in the grid is based on the .NET sorting algorithms and the default value comparator type. Since the string comparator depends on the application's current culture, you could modify the sorting and ordering of the data by changing the culture.

For more information, see the following MSDN help articles:

• Comparing and Sorting Data for a Specific Culture

• CultureInfo.DefaultThreadCurrentUICulture Property

Changing the culture affects other formatting in your page, like decimal separators, month names, etc.

Sorting Expressions

The sorting is controlled by the sorting expressions of the GridTableView object:

• You can specify the SortExpressions property collection declaratively to provide an initial sort order.

• You can manipulate the sorting expressions at runtime to alter the sort order of the columns.

  

Customizing the Sorting Arrows

An easy way to change the appearance of the RadGrid sort arrows is to use the SortAscImageUrl and SortDescImageUrl properties, which are set per column. For example:

ASP.NET

<telerik:GridBoundColumn SortAscImageUrl="MySortAscImage.gif" SortDescImageUrl="MySortDescImage.gif" />

If you use auto-generated columns, you can also set the SortAscImageUrl and SortDescImageUrl properties programmatically, for example in ColumnCreated:

C#

protected void RadGrid1_ColumnCreated(object sender, GridColumnCreatedEventArgs e)
{
    e.Column.SortAscImageUrl = "MySortAscImage.gif";
}

VB

Protected Sub RadGrid1_ColumnCreated(ByVal sender As Object, ByVal e As GridColumnCreatedEventArgs)
    e.Column.SortAscImageUrl = "MySortAscImage.gif"
End Sub

Setting the Background Color of Sorted Columns

To provide a visual hint about the sorted columns, you can specify a different background color for the sorted columns as follows:

• By setting SortingSettings -> EnableSkinSortStyles to True (default value), which automatically applies the sort color from the corresponding embedded grid skins.

• By setting the SortingSettings.SortedBackColor property of the RadGrid control.

• By setting the SortedBackColor property of a particular grid column (GridColumn object).

Setting SortedBackColor of a particular column overrides the setting of the SortingSettings.SortedBackColor property of the entire grid.

See Also

• Multi-Column Sorting

• Sort Expressions

• Controlling Sort Modes