NGWS SDK Documentation  

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ColumnsCollection.Add (String, Type)

Creates and adds a DataColumn with the specified name and type to the columns collection.

[Visual Basic]
Overloads Public Function Add( _
   ByVal columnName As String, _
   ByVal type As Type _
) As DataColumn
[C#]
public DataColumn Add(
   string columnName,
   Type type
);
[C++]
public: DataColumn* Add(
   String* columnName,
   Type* type
);
[JScript]
public function Add(
   columnName : String,
   type : Type
) : DataColumn;

Parameters

columnName
The ColumnName to create the column with.
type
The column's DataType.

Return Value

The newly created DataColumn.

Exceptions

Exception Type Condition
DuplicateNameException The collection already has a column with the same name (the comparison is not case-sensitive).
InvalidExpressionException The column has a compute expression and it can't be bound.

Remarks

If a null reference (in Visual Basic Nothing) or an empty string ("") is passed in for the name, a default name ("Column1", "Column2", etc.) is given to the column.

The Contains method determine whether a column with the proposed name already exists in the collection.

If the collection is succesfully changed by adding or removing columns, the OnCollectionChanged event occurs.

Example [Visual Basic]

The following example creates and adds a new DataColumn to a ColumnsCollection of a DataTable.

[Visual Basic]

Private Sub AddColumn()
   Dim cols As ColumnsCollection
   Dim myCol As DataColumn
   cols = New DataSet1.Tables("Orders").Columns

   ' Add a new column and return it.
   myCol = cols.Add("Total", System.Type.GetType("System.Currency"))
   myCol.ReadOnly = True
   myCol.Unique = False
End Sub

See Also

ColumnsCollection Class | ColumnsCollection Members | System.Data Namespace | ColumnsCollection.Add Overload List | ColumnName | DataType | Expression