A dialog appears confirming the status of the connection.

5.Click OK to return to the Borland Data Provider: Connections Editor dialog.
6.Click OK to return to the Data Adapter Configuration dialog.
In the Command tab, the areas for Tables and Columns are updated with information from your connection.

于是把BdpConnection1的ConnectionString属性设为databas=localhost:g:\Program
Files\Borland\Interbase\Examples\Database\employee.gdb;assembly=Borland.Data.Interbase,Version=2.0.0.0,Culture=neutral,Public
KeyToken=91d62ebb5b0d1b1b;vendorclient=gds32.dll;provider=Interbase;username=sysdba;password=masterkey
BdpDataAdapter1的Active属性设为true

去掉所加按钮及其代码，再次编译运行，一切正常。