DataRowView クラス

定義

public ref class DataRowView : System::ComponentModel::ICustomTypeDescriptor, System::ComponentModel::IDataErrorInfo, System::ComponentModel::IEditableObject, System::ComponentModel::INotifyPropertyChanged

public ref class DataRowView : System::ComponentModel::ICustomTypeDescriptor, System::ComponentModel::IDataErrorInfo, System::ComponentModel::IEditableObject

public class DataRowView : System.ComponentModel.ICustomTypeDescriptor, System.ComponentModel.IDataErrorInfo, System.ComponentModel.IEditableObject, System.ComponentModel.INotifyPropertyChanged

public class DataRowView : System.ComponentModel.ICustomTypeDescriptor, System.ComponentModel.IDataErrorInfo, System.ComponentModel.IEditableObject

type DataRowView = class
    interface ICustomTypeDescriptor
    interface IDataErrorInfo
    interface IEditableObject
    interface INotifyPropertyChanged

type DataRowView = class
    interface ICustomTypeDescriptor
    interface IEditableObject
    interface IDataErrorInfo

type DataRowView = class
    interface ICustomTypeDescriptor
    interface IEditableObject
    interface IDataErrorInfo
    interface INotifyPropertyChanged

Public Class DataRowView
Implements ICustomTypeDescriptor, IDataErrorInfo, IEditableObject, INotifyPropertyChanged

Public Class DataRowView
Implements ICustomTypeDescriptor, IDataErrorInfo, IEditableObject

継承

Object

DataRowView

実装

ICustomTypeDescriptor IDataErrorInfo IEditableObject INotifyPropertyChanged

例

次の例では、 プロパティを RowVersion 使用して、 の行の状態を確認します DataRowView。 (を使用DataRowViewする別の例については、 を参照してくださいRowFilter)。

private static void DemonstrateRowVersion()
{
    // Create a DataTable with one column.
    DataTable table = new DataTable("Table");
    DataColumn column = new DataColumn("Column");
    table.Columns.Add(column);

    // Add ten rows.
    DataRow row;
    for (int i = 0; i < 10; i++)
    {
        row = table.NewRow();
        row["Column"] = "item " + i;
        table.Rows.Add(row);
    }

    table.AcceptChanges();
    // Create a DataView with the table.
    DataView view = new DataView(table);

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

    // Add one row:
    row = table.NewRow();
    row["Column"] = "World";
    table.Rows.Add(row);

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

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

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

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

    // Set the RowStateFilter to display only deleted rows.
    view.RowStateFilter = DataViewRowState.Deleted;
    PrintView(view, "Deleted");

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

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

    // Set filter to display only original rows.
    // Current values of unmodified rows are also returned.
    view.RowStateFilter = DataViewRowState.OriginalRows;
    PrintView(view, "OriginalRows");
}

private static void PrintView(DataView view, string label)
{
    Console.WriteLine("\n" + label);
    for (int i = 0; i < view.Count; i++)
    {
        Console.WriteLine(view[i]["Column"]);
        Console.WriteLine("DataViewRow.RowVersion: {0}",
            view[i].RowVersion);
    }
}

Private Sub DemonstrateRowVersion()
    Dim i As Integer
    ' Create a DataTable with one column.
    Dim table As New DataTable("Table")
    Dim column As New DataColumn("Column")
    table.Columns.Add(column)

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

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

    ' Change one row's value:
    table.Rows(1)("Column") = "Hello"

    ' Add one row:
    row = table.NewRow()
    row("Column") = "World"
    table.Rows.Add(row)

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

    ' Print those rows. Output includes "Hello" and "World".
    PrintView(view, "ModifiedCurrent and Added")

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

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

    ' Set the RowStateFilter to display only deleted rows.
    view.RowStateFilter = DataViewRowState.Deleted
    PrintView(view, "Deleted")

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

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

    ' Set filter to display only original rows.
    ' Current values of unmodified rows are also returned.
    view.RowStateFilter = DataViewRowState.OriginalRows
    PrintView(view, "OriginalRows")
End Sub

Private Sub PrintView(ByVal view As DataView, ByVal label As String)
    Console.WriteLine(ControlChars.Cr + label)
    Dim i As Integer
    For i = 0 To view.Count - 1
        Console.WriteLine(view(i)("Column"))
        Console.WriteLine("DataRowView.RowVersion: {0}", _
            view(i).RowVersion)
    Next i
End Sub

注釈

コントロールなどの DataGrid データが表示されるたびに、各行の 1 つのバージョンのみを表示できます。 表示される行は です DataRowView。

にはDataRowView、および Proposedの 4 つの異なるバージョン状態DefaultOriginalCurrentのいずれかを指定できます。

で DataRowをBeginEdit呼び出すと、編集された値が値になりますProposed。 または がCancelEdit呼び出されるまで、行には Original バージョンと バージョンがありますProposed。EndEdit CancelEditが呼び出されると、提案されたバージョンは破棄され、値は にOriginal戻ります。 が呼び出された場合 EndEdit 、 DataRowView にはバージョンがありません Proposed 。代わりに、提案された値が現在の値になります。 既定値は、既定値が定義されている列がある行でのみ使用できます。

プロパティ

メソッド

イベント

明示的なインターフェイスの実装

適用対象

スレッド セーフ

この型は、マルチスレッド読み取り操作に対して安全です。 すべての書き込み操作を同期する必要があります。

こちらもご覧ください

• DataRow