DataGridViewCell.DefaultNewRowValue Eigenschaft

Definition

Ruft den Standardwert für eine Zelle in der Zeile für neue Datensätze ab.Gets the default value for a cell in the row for new records.

public:
 virtual property System::Object ^ DefaultNewRowValue { System::Object ^ get(); };
[System.ComponentModel.Browsable(false)]
public virtual object DefaultNewRowValue { get; }
member this.DefaultNewRowValue : obj
Public Overridable ReadOnly Property DefaultNewRowValue As Object

Eigenschaftswert

Ein Object, das den Standardwert darstellt.An Object representing the default value.

Attribute

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie die DefaultNewRowValue-Eigenschaft in einer CalendarCell Klasse überschrieben wird, die von DataGridViewTextBoxCellabgeleitet ist.The following code example demonstrates how to override the DefaultNewRowValue property in a CalendarCell class that derives from DataGridViewTextBoxCell. Dieses Beispiel ist Teil eines größeren Code Beispiels, das in Vorgehensweise: Host Steuerelemente in Windows Forms DataGridView-Zellen.This example is part of a larger code example provided in How to: Host Controls in Windows Forms DataGridView Cells.

public class CalendarCell : DataGridViewTextBoxCell
{

    public CalendarCell()
        : base()
    {
        // Use the short date format.
        this.Style.Format = "d";
    }

    public override void InitializeEditingControl(int rowIndex, object 
        initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
    {
        // Set the value of the editing control to the current cell value.
        base.InitializeEditingControl(rowIndex, initialFormattedValue, 
            dataGridViewCellStyle);
        CalendarEditingControl ctl = 
            DataGridView.EditingControl as CalendarEditingControl;
        // Use the default row value when Value property is null.
        if (this.Value == null)
        {
            ctl.Value = (DateTime)this.DefaultNewRowValue;
        }
        else
        {
            ctl.Value = (DateTime)this.Value;
        }
    }

    public override Type EditType
    {
        get
        {
            // Return the type of the editing control that CalendarCell uses.
            return typeof(CalendarEditingControl);
        }
    }

    public override Type ValueType
    {
        get
        {
            // Return the type of the value that CalendarCell contains.
            
            return typeof(DateTime);
        }
    }

    public override object DefaultNewRowValue
    {
        get
        {
            // Use the current date and time as the default value.
            return DateTime.Now;
        }
    }
}
Public Class CalendarCell
    Inherits DataGridViewTextBoxCell

    Public Sub New()
        ' Use the short date format.
        Me.Style.Format = "d"
    End Sub

    Public Overrides Sub InitializeEditingControl(ByVal rowIndex As Integer, _
        ByVal initialFormattedValue As Object, _
        ByVal dataGridViewCellStyle As DataGridViewCellStyle)

        ' Set the value of the editing control to the current cell value.
        MyBase.InitializeEditingControl(rowIndex, initialFormattedValue, _
            dataGridViewCellStyle)

        Dim ctl As CalendarEditingControl = _
            CType(DataGridView.EditingControl, CalendarEditingControl)

        ' Use the default row value when Value property is null.
        If (Me.Value Is Nothing) Then
            ctl.Value = CType(Me.DefaultNewRowValue, DateTime)
        Else
            ctl.Value = CType(Me.Value, DateTime)
        End If
    End Sub

    Public Overrides ReadOnly Property EditType() As Type
        Get
            ' Return the type of the editing control that CalendarCell uses.
            Return GetType(CalendarEditingControl)
        End Get
    End Property

    Public Overrides ReadOnly Property ValueType() As Type
        Get
            ' Return the type of the value that CalendarCell contains.
            Return GetType(DateTime)
        End Get
    End Property

    Public Overrides ReadOnly Property DefaultNewRowValue() As Object
        Get
            ' Use the current date and time as the default value.
            Return DateTime.Now
        End Get
    End Property

End Class

Hinweise

Die DefaultNewRowValue-Eigenschaft in der Basisklasse DataGridViewCell gibt immer nullzurück.The DefaultNewRowValue property in the base class DataGridViewCell always returns null. Diese Eigenschaft kann jedoch in abgeleiteten Zell Klassen überschrieben werden, um andere Standardwerte zurückzugeben.However, this property can be overridden in derived cell classes to return other default values.

Der von dieser Eigenschaft zurückgegebene Wert wird angezeigt, wenn sich die Zelle in der Zeile für neue Datensätze befindet.The value returned by this property is displayed if the cell is in the row for new records. Dieser Wert kann von einem Handler für das DataGridView.DefaultValuesNeeded-Ereignis überschrieben werden, wenn der Fokus in der Zeile für neue Datensätze eintritt.This value can be overridden by a handler for the DataGridView.DefaultValuesNeeded event when focus enters the row for new records.

Gilt für:

Siehe auch