DataViewRowState 列挙型

定義

DataRow 内のデータのバージョンを記述します。Describes the version of data in a DataRow.

この列挙体には FlagsAttribute 属性があり、そのメンバー値のビットごとの組み合わせが可能になります。

public enum class DataViewRowState
[System.Flags]
public enum DataViewRowState
type DataViewRowState = 
Public Enum DataViewRowState
継承
DataViewRowState
属性

フィールド

Added 4

新しい行。A new row.

CurrentRows 22

変更されていない行、新しい行、および変更された行を含む現在の行。Current rows including unchanged, new, and modified rows. 既定では、DataViewRowState は CurrentRows に設定されています。By default, DataViewRowState is set to CurrentRows.

Deleted 8

削除された行。A deleted row.

ModifiedCurrent 16

変更された元のデータの現在のバージョン (ModifiedOriginal を参照)。A current version of original data that has been modified (see ModifiedOriginal).

ModifiedOriginal 32

変更されたデータの元のバージョン。The original version of the data that was modified. (データは変更されても、ModifiedCurrent として利用可能です)。(Although the data has since been modified, it is available as ModifiedCurrent).

None 0

[なし] :None.

OriginalRows 42

変更されていない行と削除された行を含む元の行。Original rows including unchanged and deleted rows.

Unchanged 2

変更されていない行。An unchanged row.

次の例では DataTable が1つの列で作成されます。In the following example DataTable is created with a single column. データが変更され、DataViewRowStateに応じて、DataViewRowStateFilter が異なる行セットを表示するように設定されます。The data is changed, and the RowStateFilter of the DataView is set 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

注釈

DataViewRowState 値は、DataRowから特定のバージョンのデータを取得したり、どのバージョンが存在するかを判断したりするために使用されます。The DataViewRowState values are used either to retrieve a particular version of data from a DataRow, or to determine what versions exist.

DataView の [RowStateFilter] プロパティを設定して、表示するデータのバージョンまたはバージョンを指定します。Set the RowStateFilter property of the DataView to specify which version or versions of data you want to view.

ブール型の演算子または値を使用して、複数のバージョンを取得できます。You can use the Boolean operator Or with the values to get more than one version.

DataTableSelect メソッドで DataViewRowState を使用します。The DataTable uses DataViewRowState in the Select method.

適用対象

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