如何用VB.Net创建一个三层的数据库应用程序(1)

Public Function Get_Dataset() As super_ds    
customer_da.Fill(Super_ds1.Customers)    
order_da.Fill(Super_ds1.Orders)    
Return Super_ds1    
End Function    
Public Sub Update_Dataset()    
Super_ds1.AcceptChanges()    
End Sub 

Imports System.Web.Services    
Public Class Service1    
Inherits System.Web.Services.WebService    
‘Web Services Designer Generated Code…….    
Public Function Get_Dataset() As super_ds    
customer_da.Fill(Super_ds1.Customers)    
order_da.Fill(Super_ds1.Orders) 
Return Super_ds1    
End Function    
Public Sub Update_Dataset()    
Super_ds1.AcceptChanges()    
End Sub    
' WEB SERVICE EXAMPLE 
' The HelloWorld() example service returns the string Hello World.    
' To build, uncomment the following lines then save and build the project.    
' To test this web service, ensure that the .asmx file is the start page 
' and press F5. 
' 
' Public Function HelloWorld() As String 
' HelloWorld = "Hello World" 
' End Function 
End Class