SqlCeResultSet Class

Article
10/22/2009

An updateable, scrollable, and bindable cursor.

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

Syntax

'Declaration
<DefaultMemberAttribute("Item")> _
Public Class SqlCeResultSet
    Inherits SqlCeDataReader
    Implements IEnumerable, IListSource

[DefaultMemberAttribute("Item")] 
public class SqlCeResultSet : SqlCeDataReader, IEnumerable, IListSource

[DefaultMemberAttribute(L"Item")] 
public ref class SqlCeResultSet : public SqlCeDataReader, IEnumerable, IListSource

/** @attribute DefaultMemberAttribute("Item") */ 
public class SqlCeResultSet extends SqlCeDataReader implements IEnumerable, IListSource

DefaultMemberAttribute("Item") 
public class SqlCeResultSet extends SqlCeDataReader implements IEnumerable, IListSource

Remarks

In earlier versions of SQL Server Compact 3.5 SP1, to bind controls to data, you had to use a DataSet. While a SqlCeDataReader provides better performance than a DataSet, it is a forward-only, non-updateable cursor. In SQL Server Compact 3.5 SP1, the SqlCeResultSet provides a combination of functionality: the updateability and scrollability of the DataSet plus performance similar to a SqlCeDataReader.

To create a SqlCeResultSet, you must call the ExecuteResultSet method rather than using the object's constructor.

The ResultSetOptions let you specify the scrollabilty, updatability, and sensitivity (which determines if the SqlCeResultSet sees changes made by itself or others) of the SqlCeResultSet.

The default position of the SqlCeDataReader is prior to the first record. To begin accessing any data, you must call Read. The first Read will position the cursor to the first record. The behaviour is different from that of SqlCeResultSet.Read method. The default position of the SqlCeResultSet is the first record. Calling SqlCeResultSet.Read method immediately after creating the SqlCeResultSet will move the cursor to the second record.

Inheritance Hierarchy

System.Object
   System.MarshalByRefObject
     System.Data.Common.DbDataReader
       System.Data.SqlServerCe.SqlCeDataReader
        System.Data.SqlServerCe.SqlCeResultSet

Example

In the following example, a new SQL Server Compact 3.5 SP1 database is created. A SqlCeResultSet is then initialized to populate the dataset with data.

Dim conn As SqlCeConnection = Nothing

Try
    File.Delete("Test.sdf")

    Dim engine As New SqlCeEngine("Data Source = Test.sdf")
    engine.CreateDatabase()

    conn = New SqlCeConnection("Data Source = Test.sdf")
    conn.Open()

    Dim cmd As SqlCeCommand = conn.CreateCommand()
    cmd.CommandText = "CREATE TABLE myTable (col1 INT, col2 MONEY, col3 NVARCHAR(200))"
    cmd.ExecuteNonQuery()

    cmd.CommandText = "SELECT * FROM myTable"

    Dim rs As SqlCeResultSet = cmd.ExecuteResultSet(ResultSetOptions.Updatable Or ResultSetOptions.Scrollable)

    Dim rec As SqlCeUpdatableRecord = rs.CreateRecord()

    rec.SetInt32(0, 34)
    rec.SetDecimal(1, System.Convert.ToDecimal(44.66))
    rec.SetString(2, "Sample text")

    rs.Insert(rec)
Catch e As Exception
    MessageBox.Show(e.Message)
Finally
    conn.Close()
End Try

SqlCeConnection conn = null;

try
{
    File.Delete("Test.sdf");

    SqlCeEngine engine = new SqlCeEngine("Data Source = Test.sdf");
    engine.CreateDatabase();

    conn = new SqlCeConnection("Data Source = Test.sdf");
    conn.Open();

    SqlCeCommand cmd = conn.CreateCommand();
    cmd.CommandText = "CREATE TABLE myTable (col1 INT, col2 MONEY, col3 NVARCHAR(200))";
    cmd.ExecuteNonQuery();

    cmd.CommandText = "SELECT * FROM myTable";

    SqlCeResultSet rs = cmd.ExecuteResultSet(ResultSetOptions.Updatable | 
        ResultSetOptions.Scrollable);

    SqlCeUpdatableRecord rec = rs.CreateRecord();

    rec.SetInt32(0, 34);
    rec.SetDecimal(1, (decimal)44.66);
    rec.SetString(2, "Sample text");

    rs.Insert(rec);
}
catch (Exception e)
{
    MessageBox.Show(e.Message);
}
finally
{
    conn.Close();
}

Thread Safety

Any public static (Shared in Microsoft Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Platforms

Development Platforms

Windows Vista, Windows Mobile 5.0, Windows XP Professional with Service Pack 2 (SP2), Windows Server 2003, Windows Mobile 2003 for Pocket PC, Windows CE 5.0
Version Information
.NET Framework and NET Compact Framework
Supported in 3.5
.NET Framework
Supported in 3.0
.NET Compact Framework and .Net Framework
Supported in 2.0

Share via