在下面示例中,appMyServiceUsage状态变量被访问来递增其值。下面的代码示例是一个使用两个XML Web服务方法的XML Web服务:ServerUsage和PerSessionServerUage。ServerUsage是一个点击计数器,用于访问ServerUsage XML Web服务方法时计数,而不管客户端如何与XML Web服务方法通信。例如,如果三个客户端连续地调用ServerUsage XML Web服务方法,最后一个接收一个返回值3。而PerSessionServiceUsage则是用于一个特别的客户端会话的计数器。如果三个客户端连续地访问PerSessionServiceUsage,每个客户端都会在第一次调用的时候接收到相同的结果。[C#]
<%@ WebService Language="C#" Class="ServerUsage" %>
using System.Web.Services;
public class ServerUsage : WebService {
[ WebMethod(Description="Number of times this service has been accessed.") ]
public int ServiceUsage() {
// If the XML Web service method hasn't been accessed,
// initialize it to 1.
if (Application["appMyServiceUsage"] == null)
{
Application["appMyServiceUsage"] = 1;
}
else
{
// Increment the usage count.
Application["appMyServiceUsage"] = ((int) Application["appMyServiceUsage"]) + 1;
}
return (int) Application["appMyServiceUsage"];
}
[ WebMethod(Description="Number of times a particualr client session has accessed this XML Web service method.",EnableSession=true) ]
public int PerSessionServiceUsage() {
// If the XML Web service method hasn't been accessed, initialize
// it to 1.
if (Session["MyServiceUsage"] == null)
{
Session["MyServiceUsage"] = 1;
}
else
{
// Increment the usage count.
Session["MyServiceUsage"] = ((int) Session["MyServiceUsage"]) + 1;
}
return (int) Session["MyServiceUsage"];
}
}
[Visual Basic]
<%@ WebService Language="VB" Class="ServerUsage" %>
Imports System.Web.Services
Public Class ServerUsage
Inherits WebService
<WebMethod(Description := "Number of times this service has been accessed.")> _
Public Function ServiceUsage() As Integer
' If the XML Web service method hasn't been accessed, initialize
' it to 1.
If Application("appMyServiceUsage") Is Nothing Then
Application("appMyServiceUsage") = 1
Else
' Increment the usage count.
Application("appMyServiceUsage") = _
CInt(Application("appMyServiceUsage")) + 1
End If
Return CInt(Application("appMyServiceUsage"))
End Function
<WebMethod(Description := "Number of times a particular client session has accessed this XML Web service method.", EnableSession := True)> _
Public Function PerSessionServiceUsage() As Integer
' If the XML Web service method hasn't been accessed,
' initialize it to 1.
If Session("MyServiceUsage") Is Nothing Then
Session("MyServiceUsage") = 1
Else
' Increment the usage count.
Session("MyServiceUsage") = CInt(Session("MyServiceUsage")) + 1
End If
Return CInt(Session("MyServiceUsage"))
End Function
End Class
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