ASPxCardView.CardDeleting Event

Enables you to prevent a card from being deleted.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v23.2.dll

NuGet Package: DevExpress.Web

Declaration

C#

public event ASPxDataDeletingEventHandler CardDeleting

VB.NET

Public Event CardDeleting As ASPxDataDeletingEventHandler

Event Data

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

Property	Description
Cancel	Gets or sets a value indicating whether the event should be canceled. Inherited from CancelEventArgs.
Keys	Gets a dictionary of field name/value pairs that represent the primary key of the row to delete.
Values	Gets a dictionary of the non-key field name/value pairs for the row to delete.

Remarks

The CardDeleting event occurs when an end-user has clicked the Delete command or the ASPxCardView.DeleteCard method has been called. To cancel the delete operation, set the event parameter’s Cancel property to true.

After a card has been deleted, the ASPxCardView.CardDeleted event is raised.

Example

The following example creates an unbound column that calculates the sum of other columns and changes its values dynamically when an end-user changes a grid value in Batch edit mode.

function OnBatchEditEndEditing(s, e) {
    window.setTimeout(function () {
        var price = s.batchEditApi.GetCellValue(e.visibleIndex, "Price");
        var quantity = s.batchEditApi.GetCellValue(e.visibleIndex, "Quantity");
        s.batchEditApi.SetCellValue(e.visibleIndex, "Sum", price * quantity);
    }, 10);
}

Default.aspx

<dx:ASPxCardView ID="Grid" runat="server" KeyFieldName="ID" AutoGenerateColumns="False"
                 OnBatchUpdate="ASPxCardView1_BatchUpdate" OnCardDeleting="ASPxCardView1_CardDeleting" 
                 OnCardInserting="ASPxCardView1_CardInserting" OnCardUpdating="ASPxCardView1_CardUpdating" 
                 OnCustomUnboundColumnData="ASPxCardView1_CustomUnboundColumnData" >
    <ClientSideEvents BatchEditEndEditing="OnBatchEditEndEditing" />
    <SettingsEditing Mode="Batch" />
    <Columns>
        <dx:CardViewSpinEditColumn FieldName="Quantity" >
            <PropertiesSpinEdit DisplayFormatString="g" />
        </dx:CardViewSpinEditColumn>
        <dx:CardViewSpinEditColumn FieldName="Price" >
            <PropertiesSpinEdit DisplayFormatString="g" />
        </dx:CardViewSpinEditColumn>
        <dx:CardViewTextColumn FieldName="Sum" ReadOnly="True" UnboundType="Decimal" />
    </Columns>
    <CardLayoutProperties>
        <Items>
            <dx:CardViewCommandLayoutItem HorizontalAlign="Right" ShowDeleteButton="True" 
                                          ShowEditButton="True" ShowNewButton="True">
            </dx:CardViewCommandLayoutItem>
            <dx:CardViewColumnLayoutItem ColumnName="Quantity" />
            <dx:CardViewColumnLayoutItem ColumnName="Price" />
            <dx:CardViewColumnLayoutItem ColumnName="Sum" />
            <dx:EditModeCommandLayoutItem HorizontalAlign="Right" />
        </Items>
    </CardLayoutProperties>
</dx:ASPxCardView>

Default.aspx.cs

protected List<GridDataItem> GridData {
    get
    {
        var key = "34FAA431-CF79-4869-9488-93F6AAE81263";
        if (!IsPostBack || Session[key] == null)
            Session[key] = Enumerable.Range(1, 100).Select(i => new GridDataItem
            {
                ID = i,
                Quantity = i * 10 % 7 % i,
                Price = i * 0.5 % 3
            }).ToList();
        return (List<GridDataItem>)Session[key];
    }
}
protected void Page_Load(object sender, EventArgs e) {
    Grid.DataSource = GridData;
    Grid.DataBind();
}
protected void ASPxCardView1_BatchUpdate(object sender, DevExpress.Web.Data.ASPxDataBatchUpdateEventArgs e) {
    foreach (var args in e.InsertValues)
        InsertNewItem(args.NewValues);
    foreach (var args in e.UpdateValues)
        UpdateItem(args.Keys, args.NewValues);
    foreach (var args in e.DeleteValues)
        DeleteItem(args.Keys, args.Values);

    e.Handled = true;
}
protected void ASPxCardView1_CardInserting(object sender, DevExpress.Web.Data.ASPxDataInsertingEventArgs e) {
    InsertNewItem(e.NewValues);
    CancelEditing(e);
}
protected void ASPxCardView1_CardUpdating(object sender, DevExpress.Web.Data.ASPxDataUpdatingEventArgs e) {
    UpdateItem(e.Keys, e.NewValues);
    CancelEditing(e);
}
protected void ASPxCardView1_CardDeleting(object sender, DevExpress.Web.Data.ASPxDataDeletingEventArgs e) {
    DeleteItem(e.Keys, e.Values);
    CancelEditing(e);
}
protected void ASPxCardView1_CustomUnboundColumnData(object sender, DevExpress.Web.ASPxCardViewColumnDataEventArgs e) {
    if (e.Column.FieldName == "Sum")
    {
        decimal price = Convert.ToDecimal(e.GetListSourceFieldValue("Price"));
        int quantity = Convert.ToInt32(e.GetListSourceFieldValue("Quantity"));

        e.Value = price * quantity;
    }
}
protected GridDataItem InsertNewItem(OrderedDictionary newValues) {
    var item = new GridDataItem() { ID = GridData.Count };
    LoadNewValues(item, newValues);
    GridData.Add(item);
    return item;
}
protected GridDataItem UpdateItem(OrderedDictionary keys, OrderedDictionary newValues) {
    var id = Convert.ToInt32(keys["ID"]);
    var item = GridData.First(i => i.ID == id);
    LoadNewValues(item, newValues);
    return item;
}
protected GridDataItem DeleteItem(OrderedDictionary keys, OrderedDictionary values) {
    var id = Convert.ToInt32(keys["ID"]);
    var item = GridData.First(i => i.ID == id);
    GridData.Remove(item);
    return item;
}
protected void LoadNewValues(GridDataItem item, OrderedDictionary values) {
    item.Quantity = Convert.ToInt32(values["Quantity"]);
    item.Price = Convert.ToDouble(values["Price"]);
}
protected void CancelEditing(CancelEventArgs e) {
    e.Cancel = true;
    Grid.CancelEdit();
}
public class GridDataItem {
    public int ID { get; set; }
    public int Quantity { get; set; }
    public double Price { get; set; }
}

Default.aspx.vb

Protected ReadOnly Property GridData() As List(Of GridDataItem)
    Get
        Dim key = "34FAA431-CF79-4869-9488-93F6AAE81263"
        If (Not IsPostBack) OrElse Session(key) Is Nothing Then
            Session(key) = Enumerable.Range(1, 100).Select(Function(i) New GridDataItem With {.ID = i, .Quantity = i * 10 Mod 7 Mod i, .Price = i * 0.5 Mod 3}).ToList()
        End If
        Return DirectCast(Session(key), List(Of GridDataItem))
    End Get
End Property
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
    Grid.DataSource = GridData
    Grid.DataBind()
End Sub
Protected Sub ASPxCardView1_BatchUpdate(ByVal sender As Object, ByVal e As DevExpress.Web.Data.ASPxDataBatchUpdateEventArgs)
    For Each args In e.InsertValues
        InsertNewItem(args.NewValues)
    Next args
    For Each args In e.UpdateValues
        UpdateItem(args.Keys, args.NewValues)
    Next args
    For Each args In e.DeleteValues
        DeleteItem(args.Keys, args.Values)
    Next args

    e.Handled = True
End Sub
Protected Sub ASPxCardView1_CardInserting(ByVal sender As Object, ByVal e As DevExpress.Web.Data.ASPxDataInsertingEventArgs)
    InsertNewItem(e.NewValues)
    CancelEditing(e)
End Sub
Protected Sub ASPxCardView1_CardUpdating(ByVal sender As Object, ByVal e As DevExpress.Web.Data.ASPxDataUpdatingEventArgs)
    UpdateItem(e.Keys, e.NewValues)
    CancelEditing(e)
End Sub
Protected Sub ASPxCardView1_CardDeleting(ByVal sender As Object, ByVal e As DevExpress.Web.Data.ASPxDataDeletingEventArgs)
    DeleteItem(e.Keys, e.Values)
    CancelEditing(e)
End Sub
Protected Sub ASPxCardView1_CustomUnboundColumnData(ByVal sender As Object, ByVal e As DevExpress.Web.ASPxCardViewColumnDataEventArgs)
    If e.Column.FieldName = "Sum" Then
        Dim price As Decimal = Convert.ToDecimal(e.GetListSourceFieldValue("Price"))
        Dim quantity As Integer = Convert.ToInt32(e.GetListSourceFieldValue("Quantity"))

        e.Value = price * quantity
    End If
End Sub
Protected Function InsertNewItem(ByVal newValues As OrderedDictionary) As GridDataItem
    Dim item = New GridDataItem() With {.ID = GridData.Count}
    LoadNewValues(item, newValues)
    GridData.Add(item)
    Return item
End Function
Protected Function UpdateItem(ByVal keys As OrderedDictionary, ByVal newValues As OrderedDictionary) As GridDataItem

    Dim id_Renamed = Convert.ToInt32(keys("ID"))
    Dim item = GridData.First(Function(i) i.ID = id_Renamed)
    LoadNewValues(item, newValues)
    Return item
End Function
Protected Function DeleteItem(ByVal keys As OrderedDictionary, ByVal values As OrderedDictionary) As GridDataItem

    Dim id_Renamed = Convert.ToInt32(keys("ID"))
    Dim item = GridData.First(Function(i) i.ID = id_Renamed)
    GridData.Remove(item)
    Return item
End Function
Protected Sub LoadNewValues(ByVal item As GridDataItem, ByVal values As OrderedDictionary)
    item.Quantity = Convert.ToInt32(values("Quantity"))
    item.Price = Convert.ToDouble(values("Price"))
End Sub
Protected Sub CancelEditing(ByVal e As CancelEventArgs)
    e.Cancel = True
    Grid.CancelEdit()
End Sub
Public Class GridDataItem
    Public Property ID() As Integer
    Public Property Quantity() As Integer
    Public Property Price() As Double
End Class