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SqlDataReader.GetValues(Object[]) Method

  • Reference

Definition

Namespace:
System.Data.SqlClient
Assembly:
System.Data.SqlClient.dll
Assembly:
System.Data.dll
Package:
System.Data.SqlClient v4.9.0
Source:
System.Data.SqlClient.notsupported.cs

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

public:
 override int GetValues(cli::array <System::Object ^> ^ values);
public:
 virtual int GetValues(cli::array <System::Object ^> ^ values);
public override int GetValues (object[] values);
public int GetValues (object[] values);
override this.GetValues : obj[] -> int
abstract member GetValues : obj[] -> int
override this.GetValues : obj[] -> int
Public Overrides Function GetValues (values As Object()) As Integer
Public Function GetValues (values As Object()) As Integer

Parameters

values
Object[]

An array of Object into which to copy the attribute columns.

Returns

Int32

The number of instances of Object in the array.

Implements

GetValues(Object[])

Examples

The following example demonstrates using a correctly sized array to read all values from the current row in the supplied SqlDataReader. 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(SqlDataReader reader)
{
    // Given a SqlDataReader, 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 SqlDataReader)

    ' Given a SqlDataReader, 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.

You can pass an Object array that contains fewer than the number of columns contained in the resulting row. Only the amount of data the Object array holds is copied to the array. You can also pass an Object array whose length is more than the number of columns contained in the resulting row.

This method returns DBNull for null database columns.

Applies to

See also