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DataColumn.ColumnMapping Property

  • Reference

Definition

Namespace:
System.Data
Assembly:
System.Data.Common.dll
Assembly:
System.Data.dll
Assembly:
netstandard.dll
Source:
DataColumn.cs
Source:
DataColumn.cs
Source:
DataColumn.cs

Gets or sets the MappingType of the column.

public:
 virtual property System::Data::MappingType ColumnMapping { System::Data::MappingType get(); void set(System::Data::MappingType value); };
public virtual System.Data.MappingType ColumnMapping { get; set; }
[System.Data.DataSysDescription("DataColumnMappingDescr")]
public virtual System.Data.MappingType ColumnMapping { get; set; }
member this.ColumnMapping : System.Data.MappingType with get, set
[<System.Data.DataSysDescription("DataColumnMappingDescr")>]
member this.ColumnMapping : System.Data.MappingType with get, set
Public Overridable Property ColumnMapping As MappingType

Property Value

MappingType

One of the MappingType values.

Attributes
DataSysDescriptionAttribute

Examples

The following example sets the ColumnMapping type property of new DataColumn.

private void AddColumn(DataTable table)
{
    // Create a new column and set its properties.
    DataColumn column = new DataColumn("column",
        typeof(int), "", MappingType.Attribute);
    column.DataType = Type.GetType("System.String");
    column.ColumnMapping = MappingType.Element;

    // Add the column the table's columns collection.
    table.Columns.Add(column);
}

Private Sub AddColumn(table As DataTable )
    ' Create a new column and set its properties.
    Dim column As New DataColumn("ID", _
        Type.GetType("System.Int32"), "", MappingType.Attribute)
    column.DataType = Type.GetType("System.String")
    column.ColumnMapping = MappingType.Element

    ' Add the column the table's columns collection.
    table.Columns.Add(column)
End Sub

Remarks

The ColumnMapping property determines how a DataColumn is mapped when a DataSet is saved as an XML document using the WriteXml method.

For example, if a DataColumn is named "customerID," and its ColumnMapping property is set to MappingType.Element, the column value will produce the following XML:

<Customers>
 <customerID>ALFKI</customerID>
......
 </Customers>
 <Orders>
 <OrderID>12345</OrderID>
 <customerID>ALFKI</customerID>
......
 </Orders>

However, if the same column is mapped to MappingType.Attribute, the following XML is produced:

<Customers customerID="ALFKI"........more attributes.....>
 <Order orderID="1234"....more attributes..../>
 <Order orderID="1234"....more attributes..../>
...... More orders for this customer
 </Customers>

Use the DataColumn constructor that contains the type argument to specify how the DataColumn is mapped when its DataSet is transformed to an XML document.

The ColumnMapping property corresponds to the constructor argument type.

Applies to

See also