通过因特网产生许多服务请求可能影响客户应用程序的性能。当设计你的XML Web服务时，通过创建把有关信息集中在一起的方法可以有效利用服务请求。例如，假定你有一个XML Web服务，用来检索一本书的信息。我们可以创建一个在一条服务请求中返回所有的信息的方法，来代替单独的检索书名、作者和出版社的方法。一次传送大块的信息比多次传送小块的信息更有效率。
下面的代码示例解释如何把有关信息组织到单个XML Web服务方法中。
| [C#] ＜%@ WebService Language="C#" Class="DataService" %＞ using System; using System.Data; using System.Data.SqlClient; using System.Web.Services; public class DataService { [WebMethod] public DataSet GetTitleAuthors() { SqlConnection myConnection = new SqlConnection("Persist Security Info=False;Integrated Security=SSPI;server=localhost;database=pubs"); SqlDataAdapter myCommand1 = new SqlDataAdapter ("select * from Authors", myConnection); SqlDataAdapter myCommand2 = new SqlDataAdapter("select * from Titles", myConnection); DataSet ds = new DataSet(); myCommand1.Fill(ds, "Authors"); myCommand2.Fill(ds, "Titles"); return ds; } } [Visual Basic] ＜%@ WebService Language="VB" Class="DataService" %＞ Imports System Imports System.Data Imports System.Data.SqlClient Imports System.Web.Services Public Class DataService ＜WebMethod＞ _ Public Function GetTitleAuthors() As DataSet Dim myConnection As New SqlConnection("Persist Security Info=False;Integrated Security=SSPI;server=localhost;database=pubs") Dim myCommand1 As New SqlDataAdapter("select * from Authors", myConnection) Dim myCommand2 As New SqlDataAdapter("select * from Titles", myConnection) Dim ds As New DataSet() myCommand1.Fill(ds, "Authors") myCommand2.Fill(ds, "Titles") Return ds End Function End Class |
| [C#] ＜%@ WebService Language="C#" Class="Add" %＞ using System; using System.Web.Services; abstract public class MathService : WebService { [WebMethod] abstract public float CalculateTotal(float a, float b); } public class Add : MathService { [WebMethod] override public float CalculateTotal(float a, float b) { return a + b; } } public class Subtract : MathService { [WebMethod] override public float CalculateTotal(float a, float b) { return a - b; } } public class Multiply : MathService { [WebMethod] override public float CalculateTotal(float a, float b) { return a * b; } } public class Divide : MathService { [WebMethod] override public float CalculateTotal(float a, float b) { if (b==0) return -1; else return a / b; } } [Visual Basic] ＜%@ WebService Language="VB" Class="Add" %＞ Imports System Imports System.Web.Services MustInherit Public Class MathService : Inherits WebService ＜WebMethod＞ _ Public MustOverride Function CalculateTotal(a As Single, _ b As Single) As Single End Class Public Class Add : Inherits MathService ＜WebMethod＞ Public Overrides Function CalculateTotal(a As Single, b As Single) As Single Return a + b End Function End Class Public Class Subtract : Inherits MathService ＜WebMethod＞ Public Overrides Function CalculateTotal(a As Single, b As Single) As Single Return a - b End Function End Class Public Class Multiply : Inherits MathService ＜WebMethod＞ Public Overrides Function CalculateTotal(a As Single, b As Single) As Single Return a * b End Function End Class Public Class Divide : Inherits MathService ＜WebMethod＞ Public Overrides Function CalculateTotal(a As Single, b As Single) As Single If b = 0 Then Return - 1 Else Return a / b End If End Function End Class |
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