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UniqueConstraint.Columns Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System.Data
Assembly:
System.Data.Common.dll
Assembly:
System.Data.dll
Assembly:
netstandard.dll
Origine:
UniqueConstraint.cs
Origine:
UniqueConstraint.cs
Origine:
UniqueConstraint.cs

Ottiene la matrice delle colonne su cui agisce questo vincolo.

public:
 virtual property cli::array <System::Data::DataColumn ^> ^ Columns { cli::array <System::Data::DataColumn ^> ^ get(); };
public virtual System.Data.DataColumn[] Columns { get; }
[System.Data.DataSysDescription("KeyConstraintColumnsDescr")]
public virtual System.Data.DataColumn[] Columns { get; }
member this.Columns : System.Data.DataColumn[]
[<System.Data.DataSysDescription("KeyConstraintColumnsDescr")>]
member this.Columns : System.Data.DataColumn[]
Public Overridable ReadOnly Property Columns As DataColumn()

Valore della proprietà

DataColumn[]

Matrice di oggetti DataColumn.

Attributi
DataSysDescriptionAttribute

Esempio

Nell'esempio seguente vengono restituiti gli DataColumn oggetti vincolati dall'oggetto UniqueConstraint .

Private Sub GetColsFromConstraint()
    Dim dataColumns() As DataColumn

    ' Get a named relation from a DataSet.
    Dim dataRelation As DataRelation
    dataRelation = DataSet1.Relations("CustomerOrders")

    ' Get the ParentKeyConstraint
    Dim uniqueConstraint As UniqueConstraint
    uniqueConstraint= dataRelation.ParentKeyConstraint

    ' Get the DataColumn objects being constrained.
    dataColumns = uniqueConstraint.Columns

    ' Print the column name of each column.
    Dim i As Integer
    For i = 0 to dataColumns.GetUpperBound(0)
       Console.Write(dataColumns(i).ColumnName)
    Next i
 End Sub

Si applica a

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