Gets or sets the number of seconds the response should be held in the cache.
Assembly: System.Web.Services (in System.Web.Services.dll)
When caching is enabled requests and responses are held in memory on the server for at least the cache duration so caution must be used if you expect requests or responses to be very large or you expect requests to vary widely.
There are two issues that can affect output caching in an ASP.NET 2.0 Web service application.
In ASP.NET 2.0 the HTTP method of the test page has changed from GET to POST. However, POSTs are not normally cached. If you change the test page in an ASP.NET 2.0 Web service application to use GET, caching works properly.
In addition, HTTP indicates that a user agent (the browser or calling application) should be able to override server caching by setting the "Cache-Control" to "no-cache". ASP.NET applications, therefore, ignore cached results when they find a "no-cache" header.
The following example places the result of the call to the ServiceUsage XML Web service method in the cache for 60 seconds. Any time an XML Web service client executes the ServiceUsage XML Web service method during that time, the same result is returned.
<%@ WebService Language="VB" Class="Counter" %> Imports System.Web.Services Imports System Imports System.Web Public Class Counter Inherits WebService <WebMethod(Description := "Number of times this service has been accessed", _ CacheDuration := 60, _ MessageName := "ServiceUsage")> _ Public Function ServiceUsage() As Integer ' If the XML Web service has not been accessed, initialize it to 1. If Application("MyServiceUsage") Is Nothing Then Application("MyServiceUsage") = 1 Else ' Increment the usage count. Application("MyServiceUsage") = CInt(Application("MyServiceUsage")) + 1 End If ' Return the usage count. Return CInt(Application("MyServiceUsage")) End Function End Class