ASPxGridView.CustomColumnSort Event

Allows you to apply a custom sort algorithm to a column.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v24.2.dll

Declaration

C#

public event ASPxGridViewCustomColumnSortEventHandler CustomColumnSort

VB.NET

Public Event CustomColumnSort As ASPxGridViewCustomColumnSortEventHandler

Event Data

The CustomColumnSort event's data class is CustomColumnSortEventArgs. The following properties provide information specific to this event:

Property	Description
Column	Gets the column whose values are being compared.
Handled	Gets or sets whether a comparison operation is handled, and therefore, no default processing is required. Inherited from GridCustomColumnSortEventArgs.
ListSourceRowIndex1	Gets the index in the data source of the first of the two data items (row, card or record) being compared. Inherited from GridCustomColumnSortEventArgs.
ListSourceRowIndex2	Gets the index in the data source of the second of the two data items (row, card or record) being compared. Inherited from GridCustomColumnSortEventArgs.
Result	Gets or sets the result of a custom comparison. Inherited from GridCustomColumnSortEventArgs.
SortOrder	Gets the sort order applied to the column (row for ASPxVerticalGrid) being processed. Inherited from GridCustomColumnSortEventArgs.
Value1	Gets the first value being compared. Inherited from GridCustomColumnSortEventArgs.
Value2	Gets the second value being compared. Inherited from GridCustomColumnSortEventArgs.

The event data class exposes the following methods:

Method	Description
GetRow1Value(String)	Returns the specified column’s value in the first data item (row, card or record) being compared. Inherited from GridCustomColumnSortEventArgs.
GetRow2Value(String)	Returns the specified column’s value in the second data item (row, card or record) being compared. Inherited from GridCustomColumnSortEventArgs.

Remarks

Set the SortMode property to Custom and handle the CustomColumnSort event to apply a custom sort algorithm to a column.

When this event fires, the control compares row values (the Value1 and Value2 argument properties) within the processed column (the Column argument property).

To define the column’s sort algorithm, set the Result argument property to one of the following values:

-1

The grid places the first row above the second row in the ascending sort mode and below the second row in the descending sort mode.

1

The grid places the first row below the second row in the ascending sort mode and above the second row in the descending sort mode.

0

Indicates that the rows are equivalent according to the comparison condition. The grid sorts them, based on their indices in the data source.

Set the Handled argument property to true to indicate that the current comparison operation is handled. If the value is set to false, the control ignores the result of the custom comparison and uses the default mechanism to compare row values.

Example

The example below sorts the Country column by character length in descending order.

ASPX

<dx:ASPxGridView ID="ASPxGridView1" runat="server" AutoGenerateColumns="false"
    OnCustomColumnSort="grid_CustomColumnSort">
    <Columns>
        <dx:GridViewDataColumn FieldName="Country" SortOrder="Descending">
            <Settings SortMode="Custom" />
        </dx:GridViewDataColumn>
        <%--...--%>
    </Columns>
</dx:ASPxGridView>

C#

protected void grid_CustomColumnSort(object sender, DevExpress.Web.CustomColumnSortEventArgs e) {
    if(e.Column.FieldName == "Country") {
        e.Handled = true;
        string s1 = e.Value1.ToString(), s2 = e.Value2.ToString();
        if(s1.Length > s2.Length)
            e.Result = 1;
        else
            if(s1.Length == s2.Length)
            e.Result = Comparer.Default.Compare(s1, s2);
        else
            e.Result = -1;
    }
}

VB.NET

Protected Sub grid_CustomColumnSort(ByVal sender As Object, ByVal e As DevExpress.Web.CustomColumnSortEventArgs)
    If e.Column.FieldName = "Country" Then
        e.Handled = True
        Dim s1 As String = e.Value1.ToString(), s2 As String = e.Value2.ToString()

        If s1.Length > s2.Length Then
            e.Result = 1
        ElseIf s1.Length = s2.Length Then
            e.Result = Comparer.[Default].Compare(s1, s2)
        Else
            e.Result = -1
        End If
    End If
End Sub