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SqlCeDataReader.Read Method

Advances SqlCeDataReader to the next record.

Namespace: System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (in system.data.sqlserverce.dll)

Syntax

'Declaration
Public Overrides Function Read As Boolean
'Usage
Dim instance As SqlCeDataReader
Dim returnValue As Boolean

returnValue = instance.Read
public override bool Read ()
public:
virtual bool Read () override
public boolean Read ()
public override function Read () : boolean
Not applicable.

Return Value

true if there are more rows; otherwise, false.

Remarks

The default position of the SqlCeDataReader is prior to the first record. To begin accessing any data, you must call Read.

While SqlCeDataReader is in use, the associated SqlCeConnection is busy serving it until you call Close.

Example

The following example creates a SqlCeConnection, a SqlCeCommand, and a SqlCeDataReader. The example reads through the data and writes it out to the console. Finally, the example closes the SqlCeDataReader, then the SqlCeConnection.

Dim conn As SqlCeConnection = Nothing
Dim cmd As SqlCeCommand = Nothing
Dim rdr As SqlCeDataReader = Nothing

Try
    ' Open the connection and create a SQL command
    '
    conn = New SqlCeConnection("Data Source = AdventureWorks.sdf")
    conn.Open()
    
    cmd = New SqlCeCommand("SELECT * FROM DimEmployee", conn)
    
    rdr = cmd.ExecuteReader()
    
    ' Iterate through the results
    '
    While rdr.Read()
        Dim employeeID As Integer = rdr.GetInt32(0) ' or: rdr["EmployeeKey"];
        Dim lastName As String = rdr.GetString(5) ' or: rdr["FirstName"];
    End While
    
    ' Always dispose data readers and commands as soon as practicable
    '
    rdr.Close()
    cmd.Dispose()
Finally
    ' Close the connection when no longer needed
    '
    conn.Close()
End Try
SqlCeConnection conn = null;
SqlCeCommand cmd = null;
SqlCeDataReader rdr = null;

try
{
    // Open the connection and create a SQL command
    //
    conn = new SqlCeConnection("Data Source = AdventureWorks.sdf");
    conn.Open();

    cmd = new SqlCeCommand("SELECT * FROM DimEmployee", conn);

    rdr = cmd.ExecuteReader();

    // Iterate through the results
    //
    while (rdr.Read())
    {
        int employeeID = rdr.GetInt32(0);   // or: rdr["EmployeeKey"];
        string lastName = rdr.GetString(5); // or: rdr["FirstName"];
    }

    // Always dispose data readers and commands as soon as practicable
    //
    rdr.Close();
    cmd.Dispose();
}
finally
{
    // Close the connection when no longer needed
    //
    conn.Close();
}

Platforms

Windows CE, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows XP Professional x64 Edition, Windows XP SP2

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

Version Information

.NET Framework

Supported in: 3.0

.NET Compact Framework

Supported in: 2.0, 1.0

See Also

Reference

SqlCeDataReader Class
SqlCeDataReader Members
System.Data.SqlServerCe Namespace