GetAdapter method

The method returns a new object of type DbDataAdapter, specific to this connection. This object is used to fill the table with data.

The following parameters are passed to the method:

Parameter	Description
selectCommand	SQL query text.
connection	Object of type DbConnection, created in the GetConnection method.
Parameters	Query parameters, if defined.

Let's look at an example implementation of this method in MsSqlDataConnection:

public override DbDataAdapter GetAdapter(string selectCommand, DbConnection connection,
  CommandParameterCollection parameters)
{
  SqlDataAdapter adapter = new SqlDataAdapter(selectCommand, connection as SqlConnection);
  foreach (CommandParameter p in parameters)
  {
    SqlParameter parameter = adapter.SelectCommand.Parameters.Add(p.Name, (SqlDbType)p.DataType, p.Size);
    parameter.Value = p.Value;
  }
  return adapter;
}

The method creates an adapter specific to MS SQL, fills the query parameters and returns the adapter. The parameters should be described in more detail. The query text may contain parameters. In this case, a collection of parameters in the parameters variable is passed to the method - these are the parameters defined in the FastReport designer when the query was created. You must add the parameters to the adapter.SelectCommand.Parameters list. Each parameter in the parameters collection has the following properties:

Property	Description
Name	Parameter name.
DataType	The data type of the parameter. This is an int type property; you must cast it to the type used for the parameters in this connection.
Size	The size of the parameter data.
Value	The value of the parameter.

Most of the time you have to override this method. It is used in two other methods, FillTableSchema and FillTableData. If your connection type doesn't use the DbConnection and DbDataAdapter objects to get information about the table and load data into it, you may not override this method. In that case, you must override the FillTableSchema and FillTableData methods.