ForeignKeyConstraint.Equals(Object) Metode
Definisi
Penting
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Mendapatkan nilai yang menunjukkan apakah saat ini ForeignKeyConstraint identik dengan objek yang ditentukan.
public:
override bool Equals(System::Object ^ key);
public override bool Equals (object? key);
public override bool Equals (object key);
override this.Equals : obj -> bool
Public Overrides Function Equals (key As Object) As Boolean
Parameter
- key
- Object
Objek yang dibandingkan dengan ini ForeignKeyConstraint . Dua ForeignKeyConstraint sama jika membatasi kolom yang sama.
Mengembalikan
true
, jika objek identik; jika tidak, false
.
Contoh
Contoh berikut membuat baru ForeignKeyConstraint dan memeriksanya terhadap anggota koleksi lain dengan Equals metode sebelum menambahkannya ke 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