ForeignKeyConstraint.Equals(Object) Metodo

Definizione

Spazio dei nomi:

System.Data

Assembly:

System.Data.Common.dll

Origine:

ForeignKeyConstraint.cs

Ottiene un valore che indica se l'elemento ForeignKeyConstraint corrente è identico all'oggetto specificato.

public:
 override bool Equals(System::Object ^ key);

public override bool Equals (object? key);

override this.Equals : obj -> bool

Public Overrides Function Equals (key As Object) As Boolean

Parametri

key

Object

Oggetto con il quale viene confrontato l'oggetto ForeignKeyConstraint. Due oggetti ForeignKeyConstraint risultano uguali se applicano vincoli alle stesse colonne.

Restituisce

Boolean

true se gli oggetti sono identici; in caso contrario, false .

Esempio

Nell'esempio seguente viene creato un nuovo ForeignKeyConstraint oggetto e viene controllato in base ad altri membri della raccolta con il Equals metodo prima di aggiungerlo a un oggetto ConstraintCollection.

private void CreateConstraint(DataSet dataSet)
{
   // Create the ForignKeyConstraint with two DataColumn objects.
   DataColumn parentCol = dataSet.Tables["Customers"].Columns["id"];
   DataColumn childCol = dataSet.Tables["Orders"].Columns["OrderID"];
   ForeignKeyConstraint fkeyConstraint =
      new ForeignKeyConstraint("fkConstraint", parentCol, childCol);

   // Test against existing members using the Equals method.
   foreach(ForeignKeyConstraint testConstraint in
       dataSet.Tables["Orders"].Constraints)
   {
      if(fkeyConstraint.Equals(testConstraint)){
         Console.WriteLine("Identical ForeignKeyConstraint!");
          // Insert code to delete the duplicate object,
          // or stop the procedure.
      }
   }
}

Private Sub CreateConstraint(dataSet As DataSet)
    ' Create the ForignKeyConstraint with two DataColumn objects.
    Dim parentCol As DataColumn = _
       dataSet.Tables("Customers").Columns("id")
    Dim childCol As DataColumn = _
       dataSet.Tables("Orders").Columns("OrderID")
    Dim fkeyConstraint As _
       New ForeignKeyConstraint("fkConstraint", parentCol, childCol)

    ' Test against existing members using the Equals method.
    Dim testConstraint As ForeignKeyConstraint
    For Each testConstraint In  dataSet.Tables("Orders").Constraints
        If fkeyConstraint.Equals(testConstraint) Then
            Console.WriteLine("Identical ForeignKeyConstraint!")
            ' Insert code to delete the duplicate object, 
            ' or stop the procedure.
        End If
    Next testConstraint
End Sub