SqlCeDataAdapter Class

Článek
10/22/2009

Represents a set of data commands and a database connection that are used to fill the DataSet and update the data source.

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

Syntax

'Declaration
Public NotInheritable Class SqlCeDataAdapter
    Inherits DbDataAdapter
    Implements ICloneable

public sealed class SqlCeDataAdapter : DbDataAdapter, ICloneable

public ref class SqlCeDataAdapter sealed : public DbDataAdapter, ICloneable

public final class SqlCeDataAdapter extends DbDataAdapter implements ICloneable

public final class SqlCeDataAdapter extends DbDataAdapter implements ICloneable

Remarks

The SqlCeDataAdapter serves as a bridge between a DataSet and data source. It is used for retrieving data from, and saving data to, the data source. The SqlCeDataAdapter provides this bridge by using Fill to load data from the data source into the DataSet, and using Update to send changes made in the DataSet back to the data source.

When the SqlCeDataAdapter fills a DataSet, it creates the necessary tables and columns for the returned data if they do not already exist. However, primary key information will not be included in the implicitly created schema unless the MissingSchemaAction property is set to AddWithKey. You can also have the SqlCeDataAdapter create the schema of the DataSet, including primary key information, before filling it with data by using FillSchema.

The SqlCeDataAdapter includes the SelectCommand, InsertCommand, DeleteCommand, UpdateCommand, and TableMappings properties to facilitate the loading and updating of data.

When you create an instance of SqlCeDataAdapter, properties are set to their initial values. For a list of these values, see the SqlCeDataAdapter constructor.

Inheritance Hierarchy

System.Object
   System.MarshalByRefObject
     System.ComponentModel.Component
       System.Data.Common.DataAdapter
         System.Data.Common.DbDataAdapter
          System.Data.SqlServerCe.SqlCeDataAdapter

Example

The following example uses the SqlCeCommand, SqlCeDataAdapter, and SqlCeConnection to select records from a data source and populate a DataSet with the selected rows. The populated DataSet is then returned. To accomplish this, the method is passed an initialized DataSet, a connection string, and a query string that is an SQL SELECT statement.

Try
    Dim strDataSource As String
    strDataSource = "" & _
        "Data Source = C:\Program Files\" & _
        "Microsoft SQL Server Compact Edition\v3.5\Samples\" & _
        "Northwind.sdf"
    Dim conn As New SqlCeConnection
    conn.ConnectionString = strDataSource & ";Password='<password>'"

    Dim selectCmd As SqlCeCommand = conn.CreateCommand
    selectCmd.CommandText = "SELECT * FROM Employees"

    Dim adp As New SqlCeDataAdapter(selectCmd)

    Dim ds As New DataSet

    ' Note: Fill will leave the connection in its original state;
    ' In this case, the connection was closed so it will be left closed
    adp.Fill(ds)

    Console.WriteLine(("The SqlCeDataAdapter succesfully filled " & _
                       ds.Tables.Item(0).Rows.Count & " rows in the DataSet!"))
Catch ds As Exception
    Console.WriteLine(ds.Message)
Finally
    Console.WriteLine(vbNewLine & vbNewLine & vbNewLine & _
                      "Press any key to continue...")
    Console.ReadKey()
End Try

try
{
    string strDataSource =
        @"Data Source = C:\Program Files\" +
        @"Microsoft SQL Server Compact Edition\v3.5\Samples\" +
        @"Northwind.sdf";
    SqlCeConnection conn = new SqlCeConnection();
    conn.ConnectionString = strDataSource + ";Password='<password>'";

    SqlCeCommand selectCmd = conn.CreateCommand();
    selectCmd.CommandText = "SELECT * FROM Employees";

    SqlCeDataAdapter adp = new SqlCeDataAdapter(selectCmd);

    DataSet ds = new DataSet();

    // Note: Fill will leave the connection in its original state;
    // In this case, the connection was closed so it will be left closed
    //
    adp.Fill(ds);
    
    Console.WriteLine("The SqlCeDataAdapter succesfully filled " +
        ds.Tables[0].Rows.Count + " rows in the DataSet!");
}
catch (Exception ex)
{
    Console.WriteLine(ex.Message);
}
finally
{
    Console.WriteLine("\n\n\nPress any key to continue...");
    Console.ReadKey();
}

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

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