BindingManagerBase.Current 屬性
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
當在衍生類別中被覆寫時,會得到目前的物件。
public:
abstract property System::Object ^ Current { System::Object ^ get(); };
public abstract object Current { get; }
member this.Current : obj
Public MustOverride ReadOnly Property Current As Object
屬性值
代表 Object 當前物件的 。
範例
以下程式碼範例在事件中列印物件的值 CurrentBindingManagerBaseCurrentChanged 。 範例假設資料來源包含 DataTable 一個 DataColumn 名為 CustName的 。
void Current_Changed( Object^ sender, EventArgs^ /*e*/ )
{
BindingManagerBase^ bm = dynamic_cast<BindingManagerBase^>(sender);
/* Check the type of the Current object. If it is not a
DataRowView, exit the method. */
if ( bm->Current->GetType() != DataRowView::typeid )
return;
// Otherwise, print the value of the column named "CustName".
DataRowView^ drv = dynamic_cast<DataRowView^>(bm->Current);
Console::Write( "CurrentChanged): " );
Console::Write( drv[ "CustName" ] );
Console::WriteLine();
}
private void Current_Changed(object sender, EventArgs e)
{
BindingManagerBase bm = (BindingManagerBase) sender;
/* Check the type of the Current object. If it is not a
DataRowView, exit the method. */
if(bm.Current.GetType() != typeof(DataRowView)) return;
// Otherwise, print the value of the column named "CustName".
DataRowView drv = (DataRowView) bm.Current;
Console.Write("CurrentChanged): ");
Console.Write(drv["CustName"]);
Console.WriteLine();
}
Private Sub Current_Changed(sender As Object, e As EventArgs)
Dim bm As BindingManagerBase = CType(sender, BindingManagerBase)
' Check the type of the Current object. If it is not a
' DataRowView, exit the method.
If bm.Current.GetType() IsNot GetType(DataRowView) Then
Return
End If
' Otherwise, print the value of the column named "CustName".
Dim drv As DataRowView = CType(bm.Current, DataRowView)
Console.Write("CurrentChanged): ")
Console.Write(drv("CustName"))
Console.WriteLine()
End Sub
備註
該 Current 物件包含資料來源中當前項目的值。 要使用當前項目的值,你必須將該項目鑄造成 包含於 的物件 DataSource。Type 例如,a DataTable 包含 DataRowView 物件。 要判斷目前物件的類型,請使用 GetType and ToString 方法。
Note
當 是 DataSourceDataSet、 DataViewManager或 DataTable時,你實際上綁定於 DataView。 因此,每個 Current 物體都是物 DataRowView 體。