DataTableCollection.RemoveAt(Int32) Methode

Definition

Namespace:

System.Data

Assembly:

System.Data.Common.dll

Quelle:

DataTableCollection.cs

Entfernt das DataTable-Objekt am angegebenen Index aus der Sammlung.

public:
 void RemoveAt(int index);

public void RemoveAt (int index);

member this.RemoveAt : int -> unit

Public Sub RemoveAt (index As Integer)

Parameter

index

Int32

Der Index der zu entfernenden DataTable-Klasse.

Ausnahmen

ArgumentException

Die Auflistung enthält keine Tabelle am angegebenen Index.

Beispiele

Im folgenden Beispiel werden die Contains Methoden und CanRemove verwendet, um zu testen, ob eine Tabelle mit dem Index 10 vorhanden ist. Wenn dies der Grund ist, wird die RemoveAt -Methode aufgerufen, um die Tabelle zu entfernen.

public static void DataTableCollectionRemoveAt()
{
    // Create a DataSet with two tables and then
    // remove the tables from the collection using RemoveAt.
    DataSet dataSet = new DataSet();

    // Create Customer table.
    DataTable customerTable = new DataTable("Customers");
    customerTable.Columns.Add("customerId",
        typeof(int)).AutoIncrement = true;
    customerTable.Columns.Add("name", typeof(string));
    customerTable.PrimaryKey = new DataColumn[] { customerTable.Columns["customerId"] };

    // Create Orders table.
    DataTable ordersTable = new DataTable("Orders");
    ordersTable.Columns.Add("orderId",
        typeof(int)).AutoIncrement = true;
    ordersTable.Columns.Add("customerId", typeof(int));
    ordersTable.Columns.Add("amount", typeof(double));
    ordersTable.PrimaryKey = new DataColumn[] { ordersTable.Columns["orderId"] };

    dataSet.Tables.AddRange(new DataTable[] { customerTable, ordersTable });

    // Remove all tables.
    // First check to see if the table can be removed,
    // then remove it.
    //
    // You cannot use a foreach when removing items
    // from a collection.
    while (dataSet.Tables.Count > 0)
    {
        DataTable table = dataSet.Tables[0];
        if (dataSet.Tables.CanRemove(table))
            dataSet.Tables.RemoveAt(0);
        Console.WriteLine("dataSet has {0} tables",
            dataSet.Tables.Count);
    }
}

Public Sub DataTableCollectionRemoveAt()
    ' Create a DataSet with two tables and then
    ' remove the tables from the collection using RemoveAt.
    Dim dataSet As New DataSet()

    ' Create Customer table.
    Dim customerTable As New DataTable("Customers")
    customerTable.Columns.Add("customerId", _
        GetType(Integer)).AutoIncrement = True
    customerTable.Columns.Add("name", GetType(String))
    customerTable.PrimaryKey = New DataColumn() _
        {customerTable.Columns("customerId")}

    ' Create Orders table.
    Dim ordersTable As New DataTable("Orders")
    ordersTable.Columns.Add("orderId", _
        GetType(Integer)).AutoIncrement = True
    ordersTable.Columns.Add("customerId", GetType(Integer))
    ordersTable.Columns.Add("amount", GetType(Double))
    ordersTable.PrimaryKey = New DataColumn() _
        {ordersTable.Columns("orderId")}

    dataSet.Tables.AddRange(New DataTable() _
        {customerTable, ordersTable})

    ' Remove all tables.
    ' First check to see if the table can be removed,
    ' then remove it.
    '
    ' You cannot use a foreach when removing items
    ' from a collection.
    Do While (dataSet.Tables.Count > 0)
        Dim table As DataTable = dataSet.Tables(0)
        If (dataSet.Tables.CanRemove(table)) Then
            dataSet.Tables.RemoveAt(0)
        End If
        Console.WriteLine("dataSet has {0} tables", _
            dataSet.Tables.Count)
    Loop
End Sub

Hinweise

Das CollectionChanged Ereignis tritt auf, wenn eine Tabelle erfolgreich entfernt wurde.

Weitere Informationen

• IndexOf(DataTable)
• Contains(String)