ASPxComboBox.SelectedIndex Property

Specifies the index of the selected item.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v23.2.dll

NuGet Package: DevExpress.Web

Declaration

C#

[DefaultValue(-1)]
public int SelectedIndex { get; set; }

VB.NET

<DefaultValue(-1)>
Public Property SelectedIndex As Integer

Property Value

Type	Default	Description
Int32	-1	The zero-based index of the selected item. -1 if no item is selected within the editor.

Remarks

The SelectedIndexChanged event fires when end users change the selection in the editor list or you change the SelectedItem or SelectedIndex properties.

ASPX

<dx:ASPxComboBox ID="ASPxComboBox1" runat="server">
    <Items>
        <dx:ListEditItem Text="Afghanistan" Value="1" />
        <!--...-->         
    </Items>
</dx:ASPxComboBox>

C#

protected void Page_Load(object sender, EventArgs e){
    ASPxComboBox1.SelectedIndex = 3;
}

VB.NET

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
    ASPxComboBox1.SelectedIndex = 3
End Sub

If you bind (populate the Item collection) at runtime, make sure that you perform this operation during each round trip to the server in the control’s Init or Page_Init event. Otherwise, the SelectedIndex property may return -1.

C#

protected void ASPxComboBoxInstance_Init(object sender, EventArgs e) {  
    DevExpress.Web.ASPxEditors.ASPxComboBox cmb = (DevExpress.Web.ASPxEditors.ASPxComboBox)sender;  
    cmb.DataSource = DATA_SOURCE;  
    cmb.DataBindItems();  
}  

VB.NET

Protected Sub ASPxComboBoxInstance_Init(sender As Object, e As EventArgs)  
    Dim cmb As DevExpress.Web.ASPxEditors.ASPxComboBox = DirectCast(sender, DevExpress.Web.ASPxEditors.ASPxComboBox)  
    cmb.DataSource = DATA_SOURCE  
    cmb.DataBindItems()  
End Sub  

For more information, refer to the following property description: EnableSynchronization

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the SelectedIndex property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

asp-net-web-forms-combobox-load-items-on-callback/CS/Default.aspx.cs#L13

    cbCountries.Items.Add(DefaultCountryName);
    cbCountries.SelectedIndex = 0;
}

web-forms-pivot-grid-change-summary-display-mode/CS/SummaryDisplayMode/Default.aspx.cs#L134

        ddlSummaryDisplayType.Items.Add(Enum.GetName(typeof(PivotSummaryDisplayType), type), type);
    ddlSummaryDisplayType.SelectedIndex = 0;
}

asp-net-web-forms-scheduler-custom-adaptive-form-using-templates/CS/WebApplication1/DevExpress/ASPxSchedulerForms/AppointmentForm.ascx.cs#L204

chkRecurrence.Checked = false;
cbRecurrenceType.SelectedIndex = 0;
recInfoTypeGroup.ClientVisible = false;

VB.NET

asp-net-web-forms-combobox-load-items-on-callback/VB/Default.aspx.vb#L15

    cbCountries.Items.Add(DefaultCountryName)
    cbCountries.SelectedIndex = 0
End If

web-forms-pivot-grid-change-summary-display-mode/VB/SummaryDisplayMode/Default.aspx.vb#L153

    ddlSummaryDisplayType.SelectedIndex = 0
End Sub

asp-net-web-forms-scheduler-custom-adaptive-form-using-templates/VB/WebApplication1/DevExpress/ASPxSchedulerForms/AppointmentForm.ascx.vb#L211

chkRecurrence.Checked = False
cbRecurrenceType.SelectedIndex = 0
recInfoTypeGroup.ClientVisible = False