DataView.RowStateFilter Свойство

Определение

Возвращает или задает фильтр состояния строк, применяемый в DataView.Gets or sets the row state filter used in the DataView.

public:
 property System::Data::DataViewRowState RowStateFilter { System::Data::DataViewRowState get(); void set(System::Data::DataViewRowState value); };
public System.Data.DataViewRowState RowStateFilter { get; set; }
[System.Data.DataSysDescription("DataViewRowStateFilterDescr")]
public System.Data.DataViewRowState RowStateFilter { get; set; }
member this.RowStateFilter : System.Data.DataViewRowState with get, set
[<System.Data.DataSysDescription("DataViewRowStateFilterDescr")>]
member this.RowStateFilter : System.Data.DataViewRowState with get, set
Public Property RowStateFilter As DataViewRowState

Значение свойства

DataViewRowState

Одно из значений перечисления DataViewRowState.One of the DataViewRowState values.

Атрибуты

Примеры

В следующем примере создается DataTable с одним столбцом, а затем изменяются данные и задается RowStateFilter для, DataView чтобы отобразить различные наборы строк в зависимости от DataViewRowState .The following example creates a DataTable with a single column, and then changes the data and sets the RowStateFilter of the DataView to display different row sets, depending on the DataViewRowState.

static private void DemonstrateRowState()
{
    // Create a DataTable with one column.
    DataTable dataTable = new DataTable("dataTable");
    DataColumn dataColumn = new DataColumn("dataColumn");
    dataTable.Columns.Add(dataColumn);

    // Add ten rows.
    DataRow dataRow;
    for (int i = 0; i < 10; i++)
    {
        dataRow = dataTable.NewRow();
        dataRow["dataColumn"] = "item " + i;
        dataTable.Rows.Add(dataRow);
    }
    dataTable.AcceptChanges();

    // Create a DataView with the table.
    DataView dataView = new DataView(dataTable);

    // Change one row's value:
    dataTable.Rows[1]["dataColumn"] = "Hello";

    // Add one row:
    dataRow = dataTable.NewRow();
    dataRow["dataColumn"] = "World";
    dataTable.Rows.Add(dataRow);

    // Set the RowStateFilter to display only added and modified rows.
    dataView.RowStateFilter = DataViewRowState.Added
        | DataViewRowState.ModifiedCurrent;

    // Print those rows. Output = "Hello" "World";
    PrintView(dataView, "ModifiedCurrent and Added");

    // Set filter to display on originals of modified rows.
    dataView.RowStateFilter = DataViewRowState.ModifiedOriginal;
    PrintView(dataView, "ModifiedOriginal");

    // Delete three rows.
    dataTable.Rows[1].Delete();
    dataTable.Rows[2].Delete();
    dataTable.Rows[3].Delete();

    // Set the RowStateFilter to display only Added and modified rows.
    dataView.RowStateFilter = DataViewRowState.Deleted;
    PrintView(dataView, "Deleted");

    //Set filter to display only current.
    dataView.RowStateFilter = DataViewRowState.CurrentRows;
    PrintView(dataView, "Current");

    // Set filter to display only unchanged rows.
    dataView.RowStateFilter = DataViewRowState.Unchanged;
    PrintView(dataView, "Unchanged");

    // Set filter to display only original rows.
    dataView.RowStateFilter = DataViewRowState.OriginalRows;
    PrintView(dataView, "OriginalRows");
}

static private void PrintView(DataView dataView, string label)
{
    Console.WriteLine("\n" + label);
    for (int i = 0; i < dataView.Count; i++)
    {
        Console.WriteLine(dataView[i]["dataColumn"]);
    }
}
Private Sub DemonstrateRowState()
    Dim i As Integer

    ' Create a DataTable with one column.
    Dim dataTable As New DataTable("dataTable")
    Dim dataColumn As New DataColumn("dataColumn")
    dataTable.Columns.Add(dataColumn)

    ' Add ten rows.
    Dim dataRow As DataRow
    For i = 0 To 9
        dataRow = dataTable.NewRow()
        dataRow("dataColumn") = "item " + i.ToString()
        dataTable.Rows.Add(dataRow)
    Next i
    dataTable.AcceptChanges()

    ' Create a DataView with the table.
    Dim dataView As New DataView(dataTable)

    ' Change one row's value:
    dataTable.Rows(1)("dataColumn") = "Hello"

    ' Add one row:
    dataRow = dataTable.NewRow()
    dataRow("dataColumn") = "World"
    dataTable.Rows.Add(dataRow)

    ' Set the RowStateFilter to display only Added and modified rows.
    dataView.RowStateFilter = _
    DataViewRowState.Added Or DataViewRowState.ModifiedCurrent

    ' Print those rows. Output = "Hello" "World";
    PrintView(dataView, "ModifiedCurrent and Added")

    ' Set filter to display on originals of modified rows.
    dataView.RowStateFilter = DataViewRowState.ModifiedOriginal
    PrintView(dataView, "ModifiedOriginal")

    ' Delete three rows.
    dataTable.Rows(1).Delete()
    dataTable.Rows(2).Delete()
    dataTable.Rows(3).Delete()

    ' Set the RowStateFilter to display only Added and modified rows.
    dataView.RowStateFilter = DataViewRowState.Deleted
    PrintView(dataView, "Deleted")

    'Set filter to display only current.
    dataView.RowStateFilter = DataViewRowState.CurrentRows
    PrintView(dataView, "Current")

    ' Set filter to display only unchanged rows.
    dataView.RowStateFilter = DataViewRowState.Unchanged
    PrintView(dataView, "Unchanged")

    ' Set filter to display only original rows.
    dataView.RowStateFilter = DataViewRowState.OriginalRows
    PrintView(dataView, "OriginalRows")
End Sub

Private Sub PrintView(ByVal dataView As DataView, ByVal label As String)
    Console.WriteLine(ControlChars.Cr + label)
    Dim i As Integer
    For i = 0 To dataView.Count - 1
        Console.WriteLine(dataView(i)("dataColumn"))
    Next i
End Sub

Комментарии

Только строки, удаленные с помощью Delete метода, будут иметь RowStateFilter значение Deleted .Only rows that have been deleted by using the Delete method will have their RowStateFilter value set to Deleted. Эти строки, добавленные с помощью AddNew метода, также будут иметь свойство со значением Added .Those rows added using the AddNew method will similarly have the property set to Added.

Примечание

Использование Remove метода DataRowCollection класса не означает, что строка будет помечена как Deleted .Using the Remove method of the DataRowCollection class does not mean that a row will be marked as Deleted. Используйте Delete метод вместо того, чтобы обеспечить возможность просмотра таких строк в DataView .Use the Delete method instead to make sure that such rows can be viewed in the DataView.

Новые строки также будут видны, если параметру RowStateFilter присвоено значение ModifiedCurrent или CurrentRows .New rows will also be visible when the RowStateFilter is set to ModifiedCurrent or CurrentRows.

Удаленные строки также будут видны, если параметру RowStateFilter присвоено значение ModifiedOriginal и OriginalRows .Deleted rows will also be visible when the RowStateFilter is set to ModifiedOriginal and OriginalRows.

Применяется к

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