NGWS SDK Documentation  

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ColumnsCollection Class

Represents a collection of DataColumn objects for a DataTable.

Object
   BaseCollection
      ColumnsCollection

[Visual Basic]
Public Class ColumnsCollection
   Inherits BaseCollection
[C#]
public class ColumnsCollection : BaseCollection
[C++]
public __gc class ColumnsCollection : public BaseCollection
[JScript]
public class ColumnsCollection extends BaseCollection

Remarks

The ColumnsCollection is a major component of a DataTable. Accessed through the Columns property, the collection of columns defines the table's schema and thus determines what kind of data can be contained by a DataTable.

The ColumnsCollection contains is accessed through the Columns property of the DataTable.

The ColumnsCollection uses the standard collection methods, such as Add, Remove, Clear, and All. To determine the number of elements in the collection, use the Count property.

The Contains method verifies that a specified index or column name exists in the collection.

Requirements

Namespace: System.Data

Assembly: System.Data.dll

Example [Visual Basic]

The following example iterates through a collection of DataColumn objects and prints various properties of each column in the collection.

[Visual Basic]

Private Sub PrintDataTableColumnInfo(myTable As DataTable)
   Dim cols As ColumnsCollection
   ' Use a DataTable object's ColumnsCollection:
   cols = myTable.Columns
   ' Get all of the columns using a For Each statement:
   Dim col As DataColumn
   For Each col in cols
      Console.WriteLine(col.ColumnName)
      Console.WriteLine(col.DataType.ToString)
      Console.WriteLine(col.DefaultValue)
   Next
End Sub

See Also

ColumnsCollection Members | System.Data Namespace | Columns | DataColumn | DataTable | DataRelation | DataRow | DataSet