DataColumn Constructor (String, Type, String, MappingType)


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.

Namespace:   System.Data
Assembly:  System.Data (in System.Data.dll)

new : 
        columnName:string *
        dataType:Type *
        expr:string *
        type:MappingType -> DataColumn


Type: System.String

A string that represents the name of the column to be created. If set to null or an empty string (""), a default name will be specified when added to the columns collection.

Type: System.Type

A supported DataType.

Type: System.String

The expression used to create this column. For more information, see the Expression property.

Type: System.Data.MappingType

One of the MappingType values.

Exception Condition

No dataType was specified.

The type argument sets the ColumnMapping property. The property specifies how a DataColumn is mapped when a DataSet is transformed into an XML document. For example, if the column is named "fName," and the value it contains is "Bob," and type is set to MappingType.Attribute, the XML element would be as follows:

<Name fName = 'Bob'/>

For more information about how columns are mapped to elements or attributes, see the ColumnMapping property.

The following example constructs a computed column.

No code example is currently available or this language may not be supported.

.NET Framework
Available since 1.1
Return to top