DataTableReader.GetValues(Object[]) Method

Definition

Namespace:

System.Data

Assembly:

System.Data.Common.dll

Source:

DataTableReader.cs

Populates an array of objects with the column values of the current row.

public:
 override int GetValues(cli::array <System::Object ^> ^ values);

public override int GetValues (object[] values);

override this.GetValues : obj[] -> int

Public Overrides Function GetValues (values As Object()) As Integer

Parameters

values

Object[]

An array of Object into which to copy the column values from the DataTableReader.

Returns

Int32

The number of column values copied into the array.

Exceptions

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 .

Examples

The following example demonstrates using an array that is the correct size, to read all values from the current row in the supplied DataTableReader. In addition, the sample demonstrates using a fixed-sized array that could be either smaller or larger than the number of available columns.

private static void TestGetValues(DataTableReader reader)
{
    // Given a DataTableReader, use the GetValues
    // method to retrieve a full row of data.
    // Test the GetValues method, passing in an array large
    // enough for all the columns.
    Object[] values = new Object[reader.FieldCount];
    int fieldCount = reader.GetValues(values);

    Console.WriteLine("reader.GetValues retrieved {0} columns.",
        fieldCount);
    for (int i = 0; i < fieldCount; i++)
        Console.WriteLine(values[i]);

    Console.WriteLine();

    // Now repeat, using an array that may contain a different
    // number of columns than the original data. This should work correctly,
    // whether the size of the array is larger or smaller than
    // the number of columns.

    // Attempt to retrieve three columns of data.
    values = new Object[3];
    fieldCount = reader.GetValues(values);
    Console.WriteLine("reader.GetValues retrieved {0} columns.",
        fieldCount);
    for (int i = 0; i < fieldCount; i++)
        Console.WriteLine(values[i]);
}

Private Sub TestGetValues(ByVal reader As DataTableReader)

    ' Given a DataTableReader, use the GetValues
    ' method to retrieve a full row of data.

    ' Test the GetValues method, passing in an array large
    ' enough for all the columns.
    Dim values(reader.FieldCount - 1) As Object
    Dim fieldCount As Integer = reader.GetValues(values)
    Console.WriteLine("reader.GetValues retrieved {0} columns.", _
         fieldCount)
    For i As Integer = 0 To fieldCount - 1
        Console.WriteLine(values(i))
    Next

    Console.WriteLine()

    ' Now repeat, using an array that may contain a different 
    ' number of columns than the original data. This should work correctly,
    ' whether the size of the array is larger or smaller than 
    ' the number of columns.

    ' Attempt to retrieve three columns of data.
    ReDim values(2)
    fieldCount = reader.GetValues(values)
    Console.WriteLine("reader.GetValues retrieved {0} columns.", _
         fieldCount)
    For i As Integer = 0 To fieldCount - 1
        Console.WriteLine(values(i))
    Next
End Sub

Remarks

For most applications, this method provides an efficient means for retrieving all columns, instead of retrieving each column individually. If your intent is to retrieve all the column values from a row within the DataTableReader, the GetValues method provides the most efficient solution.

You can pass an Object array that contains fewer than the number of columns that are contained in the resulting row. Only the amount of data the Object array can hold is copied to the array. You can also pass an Object array whose length is more than the number of columns that are contained in the resulting row, in which case the additional array elements remains unchanged by the method call.

This method places DBNull in the output array for null columns.