Initializes a new instance of the DataColumn class using the specified name, data type, expression, and value that determines whether the column is an attribute.
[Visual Basic] Overloads Public Sub New( _ ByVal columnName As String, _ ByVal dataType As Type, _ ByVal expr As String, _ ByVal isAttribute As Boolean _ ) [C#] public DataColumn( string columnName, Type dataType, string expr, bool isAttribute ); [C++] public: DataColumn( String* columnName, Type* dataType, String* expr, bool isAttribute ); [JScript] public function DataColumn( columnName : String, dataType : Type, expr : String, isAttribute : Boolean );
The following example constructs a computed column.
[Visual Basic]
Private Sub CreateComputedColumn() Dim myColumn As DataColumn Dim dt As System.Type Dim strExpr As String dt = System.Type.GetType("System.Currency") strExpr = "Price * Quantity" myColumn = New DataColumn("Total", dt, strExpr, False) ' Add the column to a DataTable object's ColumnsCollection Dim myTable As DataTable myTable = DataSet1.Tables("OrderDetails").Columns.Add(myColumn) End Sub
DataColumn Class | DataColumn Members | System.Data Namespace | DataColumn Constructor Overload List | ColumnName | Caption | DefaultValue | DataTable | DataType