DataTableReader.GetString Method (Int32)

 

Gets the value of the specified column as a string.

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

Public Overrides Function GetString (
	ordinal As Integer
) As String

Parameters

ordinal
Type: System.Int32

The zero-based column ordinal

Return Value

Type: System.String

The value of the specified column.

Exception Condition
ArgumentOutOfRangeException

The index passed was outside the range of 0 to FieldCount - 1.

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.

InvalidCastException

The specified column does not contain a string.

Call IsDBNull to see if there are null values before calling this method.

The following example displays the contents of the column numbered 2 within the passed-in DataTableReader. If the value the column within a particular row is null, the code displays the text <NULL>. If the data within the column of the correct type, the example displays an error message for each row.

Private Sub PrintColumn(ByVal reader As DataTableReader)
   ' Loop through all the rows in the DataTableReader
   While reader.Read()
      If reader.IsDBNull(2) Then
         Console.Write("<NULL>")
      Else
         Try
            Console.Write(reader.GetString(2))
         Catch ex As InvalidCastException
            Console.Write("Invalid data type.")
         End Try
      End If
      Console.WriteLine()
   End While
End Sub

.NET Framework
Available since 2.0
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