ASPxGridView.CustomGroupDisplayText Event

Allows you to customize the text of group rows.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v23.2.dll

NuGet Package: DevExpress.Web

Declaration

C#

public event ASPxGridViewColumnDisplayTextEventHandler CustomGroupDisplayText

VB.NET

Public Event CustomGroupDisplayText As ASPxGridViewColumnDisplayTextEventHandler

Event Data

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

Property	Description
Column	Gets the data column that contains the cell currently being processed.
DisplayText	Enables you to set a custom text for the cell currently being processed. Inherited from ASPxGridColumnDisplayTextEventArgs.
EncodeHtml	Gets or sets a value that specifies whether the cell display text keeps any of its values that are HTML as HTML, or instead, strips out the HTML markers. Inherited from ASPxGridColumnDisplayTextEventArgs.
Kind	Gets the type of operations with grid data. Inherited from ASPxGridColumnDisplayTextEventArgs.
Value	Gets the edit value of the cell currently being processed. Inherited from ASPxGridColumnDisplayTextEventArgs.
VisibleIndex	Gets the visible index of the data item (row, card or record) where the processed cell resides. Inherited from ASPxGridColumnDisplayTextEventArgs.
VisibleRowIndex	Obsolete. Gets the visible index of the data row where the processed cell resides.

The event data class exposes the following methods:

Method	Description
GetFieldValue(Int32, String)	Returns the value of the specified data source field in the specified data item (row, card or record). Inherited from ASPxGridColumnDisplayTextEventArgs.
GetFieldValue(String)	Returns the value of the specified data source field in the current data item (row, card or record). Inherited from ASPxGridColumnDisplayTextEventArgs.

Remarks

ASPxGridView allows you to customize the text of group rows. To enable this behavior, follow the steps below:

1. Handle the CustomGroupDisplayText event.

2. Use the Value argument property to get the row value within the processed column (the Column argument property).

3. Specify the DisplayText argument property to customize the text that the grid displays within group rows.

To define the text pattern for group rows, specify the control’s GroupFormat property.

ASPX

<dx:ASPxGridView ID="ASPxGridView1" runat="server" AutoGenerateColumns="False"
    OnCustomGroupDisplayText="ASPxGridView1_CustomGroupDisplayText">
    <Columns>
        <dx:GridViewDataTextColumn FieldName="Country" />
        <%--...--%>
    </Columns>
    <Settings ShowGroupPanel="true" />
    <SettingsBehavior AllowGroup="true" />
</dx:ASPxGridView>

C#

protected void ASPxGridView1_CustomGroupDisplayText(object sender, ASPxGridViewColumnDisplayTextEventArgs e) {
    if(e.Column.FieldName == "Country") {
        e.DisplayText = "Custom value";
        ASPxGridView1.Settings.GroupFormat = string.Format("{0}: {1}", "Custom caption", e.DisplayText); 
    }
}

VB.NET

Protected Sub ASPxGridView1_CustomGroupDisplayText(ByVal sender As Object, ByVal e As ASPxGridViewColumnDisplayTextEventArgs)
    If e.Column.FieldName = "Country" Then
        e.DisplayText = "Custom Value"
        ASPxGridView1.Settings.GroupFormat = String.Format("{0}: {1}", "Custom caption", e.DisplayText)
    End If
End Sub

To apply a custom grouping algorithm to a column, set the SortMode property to Custom and handle the CustomColumnGroup event.

Example

In the example below, the grid raises the CustomColumnGroup and CustomColumnSort events to apply a custom grouping and sort algorithm to the Unit Price column.

The control also raises the CustomGroupDisplayText event to change the text within group rows.

ASPX

<dx:ASPxGridView ID="grid" runat="server" AutoGenerateColumns="False" KeyFieldName="ProductID" 
    OnCustomColumnGroup="grid_CustomColumnGroup" 
    OnCustomColumnSort="grid_CustomColumnSort" 
    OnCustomGroupDisplayText="grid_CustomGroupDisplayText">
    <GroupSummary>
        <dx:ASPxSummaryItem SummaryType="Count" />
    </GroupSummary>
    <Columns>
        <dx:GridViewDataTextColumn FieldName="ProductID" ReadOnly="True" VisibleIndex="0">
            <EditFormSettings Visible="False" />
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataTextColumn FieldName="ProductName" VisibleIndex="1" />
        <dx:GridViewDataTextColumn FieldName="UnitPrice" VisibleIndex="2" GroupIndex="0" SortIndex="0"
            SortOrder="Ascending">
            <PropertiesTextEdit DisplayFormatString="c" />
            <Settings AllowDragDrop="False" SortMode="Custom" />
        </dx:GridViewDataTextColumn>
        <dx:GridViewDataCheckColumn FieldName="Discontinued" VisibleIndex="3" />
    </Columns>
    <Settings ShowGroupedColumns="True" ShowGroupPanel="True" />
</dx:ASPxGridView>

C#

protected void grid_CustomColumnSort(object sender, DevExpress.Web.ASPxGridView.CustomColumnSortEventArgs e) {
    CompareColumnValues(e);
}

protected void grid_CustomColumnGroup(object sender, DevExpress.Web.ASPxGridView.CustomColumnSortEventArgs e) {
    CompareColumnValues(e);
}

private void CompareColumnValues(DevExpress.Web.ASPxGridView.CustomColumnSortEventArgs e) {
    if(e.Column.FieldName == "UnitPrice") {
        int res = 0;
        double x = Math.Floor(Convert.ToDouble(e.Value1) / 10);
        double y = Math.Floor(Convert.ToDouble(e.Value2) / 10);
        res = Comparer.Default.Compare(x, y);
        if(res < 0) res = -1;
        else if(res > 0) res = 1;
        if(res == 0 || (x > 9 && y > 9)) res = 0;

        e.Result = res;
        e.Handled = true;
    }
}

protected void grid_CustomGroupDisplayText(object sender, DevExpress.Web.ASPxGridView.ASPxGridViewColumnDisplayTextEventArgs e) {
    if(e.Column.FieldName == "UnitPrice") {
        double d = Math.Floor(Convert.ToDouble(e.Value) / 10);
        string displayText = string.Format("{0:c} - {1:c} ", d * 10, (d + 1) * 10);
        if(d > 9) displayText = string.Format(">= {0:c} ", 100);
        e.DisplayText = displayText;
    }
}

VB.NET

Protected Sub grid_CustomColumnSort(ByVal sender As Object, ByVal e As DevExpress.Web.ASPxGridView.CustomColumnSortEventArgs)
    CompareColumnValues(e)
End Sub

Protected Sub grid_CustomColumnGroup(ByVal sender As Object, ByVal e As DevExpress.Web.ASPxGridView.CustomColumnSortEventArgs)
    CompareColumnValues(e)
End Sub

Private Sub CompareColumnValues(ByVal e As DevExpress.Web.ASPxGridView.CustomColumnSortEventArgs)
    If e.Column.FieldName = "UnitPrice" Then
        Dim res As Integer = 0
        Dim x As Double = Math.Floor(Convert.ToDouble(e.Value1) / 10)
        Dim y As Double = Math.Floor(Convert.ToDouble(e.Value2) / 10)
        res = Comparer.[Default].Compare(x, y)

        If res < 0 Then
            res = -1
        ElseIf res > 0 Then
            res = 1
        End If

        If res = 0 OrElse (x > 9 AndAlso y > 9) Then res = 0
        e.Result = res
        e.Handled = True
    End If
End Sub

Protected Sub grid_CustomGroupDisplayText(ByVal sender As Object, ByVal e As DevExpress.Web.ASPxGridView.ASPxGridViewColumnDisplayTextEventArgs)
    If e.Column.FieldName = "UnitPrice" Then
        Dim d As Double = Math.Floor(Convert.ToDouble(e.Value) / 10)
        Dim displayText As String = String.Format("{0:c} - {1:c} ", d * 10, (d + 1) * 10)
        If d > 9 Then displayText = String.Format(">= {0:c} ", 100)
        e.DisplayText = displayText
    End If
End Sub