DataTableReader.Item Property (String)

 

Gets the value of the specified column in its native format given the column name.

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

Public Overrides ReadOnly Property Item (
	name As String
) As Object

Parameters

name
Type: System.String

The name of the column.

Property Value

Type: System.Object

The value of the specified column in its native format.

Exception Condition
ArgumentException

The name specified is not a valid column name.

DeletedRowInaccessibleException

An attempt was made to retrieve data from a deleted row.

InvalidOperationException

An attempt was made to read or access a column in a closed DataTableReader.

A case-sensitive lookup is performed first. If it fails, a second case-insensitive search is made.

This method is kana-width insensitive.

This overloaded version of M:System.Data.DataTableReader.Item corresponds to calling the M:System.Data.DataTableReader.GetOrdinal method, and then subsequently calling the GetValue method.

Given a DataTableReader and a column name, the GetValueByName procedure returns the value of the specified column. Before calling this procedure, you must create a new DataTableReader instance and call its Read method at least one time to position the row pointer on a row of data.

Private Function GetValueByName( _
   ByVal reader As DataTableReader, _
   ByVal columnName As String) As Object

   ' Consider when to use a procedure like this one carefully:
   ' If you're going to retrieve information from a column
   ' in a loop, it would be better to retrieve the column
   ' ordinal once, store the value, and use the methods
   ' of the DataTableReader class directly. 
   ' Use Item(columnName) sparingly.
   Dim columnValue As Object

   Try
      columnValue = reader.Item(columnName)
   Catch ex As ArgumentException
      ' Throw all other errors back out to the caller.
      columnValue = Nothing
   End Try
   Return columnValue
End Function

.NET Framework
Available since 2.0
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