DataRow.HasVersion(DataRowVersion) 方法

定义

命名空间:
System.Data
程序集:
System.Data.Common.dll
程序集:
netstandard.dll
程序集:
System.Data.dll

获取一个值，该值指示指定的版本是否存在。Gets a value that indicates whether a specified version exists.

public:
 bool HasVersion(System::Data::DataRowVersion version);
public bool HasVersion (System.Data.DataRowVersion version);
member this.HasVersion : System.Data.DataRowVersion -> bool
Public Function HasVersion (version As DataRowVersion) As Boolean

参数

version
DataRowVersion

DataRowVersion 值之一，用于指定行版本。One of the DataRowVersion values that specifies the row version.

返回

Boolean

如果该版本存在，则为 true；否则为 false。true if the version exists; otherwise, false.

示例

下面的示例使用 HasVersion 方法来确定列的当前值和建议的值是否相同。The following example uses the HasVersion method to determine whether the current value of a column and the proposed value are the same. 如果是这样，则取消编辑。If so, the edit is canceled. 否则，将 AcceptChanges 调用方法以结束编辑。Otherwise, the AcceptChanges method is called to end the edit.

Private Sub CheckVersionBeforeAccept()
    ' Assuming the DataGrid is bound to a DataTable.
    Dim table As DataTable = CType(DataGrid1.DataSource, DataTable)
    Dim row As DataRow = table.Rows(DataGrid1.CurrentCell.RowNumber)
    row.BeginEdit
    row(1) = Edit1.Text
    If row.HasVersion(datarowversion.Proposed) Then
       If row(1, DataRowVersion.Current) Is _
            row(1, DataRowversion.Proposed) Then
          Console.WriteLine("The original and the proposed are the same")
          row.CancelEdit
          Exit Sub
       Else
          row.AcceptChanges
       End If
    Else
       Console.WriteLine("No new values proposed")
    End If
End Sub

注解

有关更多信息，请参阅 BeginEdit 方法。See the BeginEdit method for more information.

适用于

另请参阅