DataRow.RejectChanges 方法

定義

命名空間:

System.Data

組件:

System.Data.Common.dll

來源:

DataRow.cs

拒絕自前一次呼叫 AcceptChanges() 以來，對資料列所做的所有變更。

public:
 void RejectChanges();

public void RejectChanges ();

member this.RejectChanges : unit -> unit

Public Sub RejectChanges ()

例外狀況

RowNotInTableException

資料列不屬於資料表。

範例

下列範例會建立具有 2 個資料列和 10 個資料列的簡單 DataTable 。 使用 Delete 方法刪除數DataRow個項目之後，叫用 會取消RejectChanges刪除其中一個數據列。

private void DemonstrateDeleteRow()
{
    // Create a simple DataTable with two columns and ten rows.
    DataTable table = new DataTable("table");
    DataColumn idColumn = new DataColumn("id",
        Type.GetType("System.Int32"));
    idColumn.AutoIncrement=true;
    DataColumn itemColumn = new DataColumn("item",
        Type.GetType("System.String"));
    table.Columns.Add(idColumn);
    table.Columns.Add(itemColumn);

    // Add ten rows.
    DataRow newRow;

    for(int i = 0; i <10; i++)
    {
        newRow = table.NewRow();
        newRow["item"] = "Item " + i;
        table.Rows.Add(newRow);
    }
    table.AcceptChanges();

    DataRowCollection itemColumns = table.Rows;
    itemColumns[0].Delete();
    itemColumns[2].Delete();
    itemColumns[3].Delete();
    itemColumns[5].Delete();
    Console.WriteLine(itemColumns[3].RowState.ToString());

    // Reject changes on one deletion.
    itemColumns[3].RejectChanges();

    // Change the value of the column so it stands out.
    itemColumns[3]["item"] = "Deleted, Undeleted, Edited";

    // Accept changes on others.
    table.AcceptChanges();

    // Print the remaining row values.
    foreach(DataRow row in table.Rows)
    {
        Console.WriteLine(row[0] + "\table" + row[1]);
    }
}

 Private Sub DemonstrateDeleteRow()
     ' Create a simple DataTable with two columns and ten rows.
     Dim table As New DataTable("table")
     Dim idColumn As New DataColumn("id", Type.GetType("System.Int32"))
     idColumn.AutoIncrement = True
     Dim itemColumn As New DataColumn("item", Type.GetType("System.String"))
     table.Columns.Add(idColumn)
     table.Columns.Add(itemColumn)

     ' Add ten rows.
     Dim newRow As DataRow
     
     Dim i As Integer
     For i = 0 To 9
         newRow = table.NewRow()
         newRow("item") = "Item " & i.ToString()
         table.Rows.Add(newRow)
     Next i
     table.AcceptChanges()

     Dim itemColumns As DataRowCollection = table.Rows
     itemColumns(0).Delete()
     itemColumns(2).Delete()
     itemColumns(3).Delete()
     itemColumns(5).Delete()
     Console.WriteLine(itemColumns(3).RowState.ToString())

     ' Reject changes on one deletion.
     itemColumns(3).RejectChanges()

     ' Change the value of the column so it stands out.
     itemColumns(3)("item") = "Deleted, Undeleted, Edited"

     ' Accept changes on others.
     table.AcceptChanges()

     ' Print the remaining row values.
     Dim row As DataRow
     For Each row In  table.Rows
         Console.WriteLine(row(0).ToString() & ControlChars.Tab _
            & row(1).ToString())
     Next row
End Sub

備註

當您呼叫 RejectChanges 方法時， CancelEdit 會隱含呼叫 方法來取消任何編輯。 如果 RowState 已刪除或修改，則數據列會還原為其先前的值，並 RowState 保持不變。 RowState如果 已新增 ，則會移除資料列。

另請參閱

• AcceptChanges()
• IsNull(Int32)