DataSet.OnRemoveTable(DataTable) Méthode
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protected public:
virtual void OnRemoveTable(System::Data::DataTable ^ table);
protected:
virtual void OnRemoveTable(System::Data::DataTable ^ table);
protected internal virtual void OnRemoveTable (System.Data.DataTable table);
protected virtual void OnRemoveTable (System.Data.DataTable table);
abstract member OnRemoveTable : System.Data.DataTable -> unit
override this.OnRemoveTable : System.Data.DataTable -> unit
Protected Friend Overridable Sub OnRemoveTable (table As DataTable)
Protected Overridable Sub OnRemoveTable (table As DataTable)
L’exemple suivant montre une classe dérivée de avec DataSet la OnRemoveTable méthode remplacée.
public static void DemonstrateOnRemoveTable()
{
DerivedDataSet dataSet = CreateDataSet();
if(dataSet.Tables.Count > 0)
dataSet.Tables.RemoveAt(0);
}
public class DerivedDataSet: DataSet
{
protected override void OnRemoveTable(DataTable table)
{
Console.WriteLine(
"The '{0}' DataTable has been removed from the DataSet",
table.TableName);
}
}
public static DerivedDataSet CreateDataSet()
{
// Create a DataSet with one table containing two columns.
DerivedDataSet derived = new DerivedDataSet();
// Add table to DataSet.
DataTable table = derived.Tables.Add("Items");
// Add two columns.
DataColumn column = table.Columns.Add("id", typeof(int));
column.AutoIncrement = true;
table.Columns.Add("item", typeof(int));
// Set primary key.
table.PrimaryKey = new DataColumn[] {table.Columns["id"]};
return derived;
}
Public Shared Sub DemonstrateOnRemoveTable()
Dim dataSet As DerivedDataSet = CreateDataSet()
If dataSet.Tables.Count > 0 Then dataSet.Tables.RemoveAt(0)
End Sub
Public Class DerivedDataSet
Inherits DataSet
Protected Overrides Sub OnRemoveTable(table As DataTable)
Console.WriteLine( _
"The '{0}' DataTable has been removed from the DataSet", _
table.TableName)
End Sub
End Class
Public Shared Function CreateDataSet() As DerivedDataSet
' Create a DataSet with one table containing two columns.
Dim derived As New DerivedDataSet()
' Add table to DataSet.
Dim table As DataTable = derived.Tables.Add("Items")
' Add two columns.
Dim column As DataColumn = table.Columns.Add("id", _
Type.GetType("System.Int32"))
column.AutoIncrement = True
table.Columns.Add("item", Type.GetType("System.Int32"))
' Set primary key.
table.PrimaryKey = New DataColumn() {table.Columns("id")}
return derived
End Function
Cette méthode peut être remplacée par des sous-classes pour empêcher la suppression des tables.
Produit | Versions |
---|---|
.NET | Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 2.0, 2.1 |
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