BindingManagerBase.Current 属性

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

当在派生类中被重写时，获取当前对象。

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

属性值

Object

代表当前对象的 Object。

示例

下面的代码示例在 事件中BindingManagerBaseCurrentChanged打印 对象的值Current。 该示例假定数据源是一个 DataTable 包含名为 的 DataColumnCustName。

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

注解

对象 Current 包含数据源中当前项的值。 若要使用当前项的值，必须将项 Type 强制转换为 包含 DataSource的 对象的 。 例如， 包含 DataTableDataRowView 对象。 若要确定当前对象的类型，请使用 GetType 和 ToString 方法。

备注

DataSource当 为 DataSet、 DataViewManager或 DataTable时，实际绑定到 DataView。 因此，每个对象都是 Current 一个 DataRowView 对象。

另请参阅

• CurrentChanged
• Position