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DataTableReader.GetInt64(Int32) Method

Definition

Gets the value of the specified column as a 64-bit signed integer.

public:
 override long GetInt64(int ordinal);
public override long GetInt64 (int ordinal);
override this.GetInt64 : int -> int64
Public Overrides Function GetInt64 (ordinal As Integer) As Long

Parameters

ordinal
Int32

The zero-based column ordinal.

Returns

The value of the specified column.

Exceptions

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

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

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

The specified column does not contain a 64-bit signed integer value.

Examples

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 is not of the correct type, the example displays an error message for each row.

private static void PrintColumn(DataTableReader reader)
{
    // Loop through all the rows in the DataTableReader
    while (reader.Read())
    {
        if (reader.IsDBNull(2))
        {
            Console.Write("<NULL>");
        }
        else
        {
            try
            {
                Console.Write(reader.GetInt64(2));
            }
            catch (InvalidCastException)
            {
                Console.Write("Invalid data type.");
            }
        }
        Console.WriteLine();
    }
}
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.GetInt64(2))
         Catch ex As InvalidCastException
            Console.Write("Invalid data type.")
         End Try
      End If
      Console.WriteLine()
   End While
End Sub

Remarks

No conversions are performed; therefore, the data retrieved must already be an Int64 or coercible to an Int64.

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

Applies to