日期:2008-07-18  浏览次数:20554 次

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 使用输出缓冲来改善你的XML Web服务的性能。当输出缓冲开启时,服务请求的结果被保存在输出缓冲中一段指定的时间。如果一个类似的XML Web服务请求被产生,结果可以从缓冲中取得,而不用重新计算。这样就通过减少XML Web服务服务器所需的处理来改善了XML Web服务的反馈时间。高速缓存可在客户端和服务器两者上执行。Duration属性允许你指定高速缓冲保存XML Web服务输出的时间。

  在客户端上使用输出高速缓冲的指令是:

<%@ OutputCache Duration="60" %>

  下面的代码示例显示如何在客户应用程序上使用Duration属性来指定输出高速缓冲为60秒。

[C#]
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Net" %>
<%@ OutputCache Duration="60" VaryByParam="none" %>
<HTML>
<script language="C#" runat="server">
void EnterBtn_Click(Object Src, EventArgs e)
{
 MyMath.Math math = new MyMath.Math();
 // Call the XML Web service.
 float total = math.Add(Convert.ToInt32(Num1.Text),
 Convert.ToInt32(Num2.Text));
 // Display the results in a Label control.
 Total.Text = "Total: " + total.ToString();
}
</script>
<body>
<form action="MathClient.ASPx" runat=server>
<font face="Verdana">
Enter the two numbers you want to add and press
the Total button.
<p>
Number 1:
<ASP:textbox id="Num1" runat=server/>
+ Number 2:
<ASP:textbox id="Num2" runat=server/>
= <ASP:button id="Total_Button" text="Total" OnClick="EnterBtn_Click" runat=server/>
<p>
<ASP:label id="Total" runat=server/>
</font>
</form>
</body>
</HTML>
[Visual Basic]
<%@ Page Language="VB" %>
<%@ Import Namespace="System.Net" %>
<%@ OutputCache Duration="60" VaryByParam="none" %>
<HTML>
<script language="VB" runat="server">
Sub EnterBtn_Click(Src As Object, e As EventArgs)
 Dim math As New MyMath.Math()
 ' Call the XML Web service.
 Dim addtotal As Single = math.Add(Convert.ToInt32(Num1.Text), Convert.ToInt32(Num2.Text))
 ' Display the results in a Label control.
 Total.Text = "Total: " & addtotal.ToString()
End Sub
</script>
<body>
<form action="MathClient.ASPx" runat=server>
<font face="Verdana">
Enter the two numbers you want to add and press
the Total button.
<p>
Number 1:
<ASP:textbox id="Num1" runat=server/>
+
Number 2:
<ASP:textbox id="Num2" runat=server/>
= <ASP:button id="Total_Button" text="Total" OnClick="EnterBtn_Click" runat=server/>
<p>
<ASP:label id="Total" runat=server/>
</font>
</form>
</body>
</HTML>

  你还可以使用WebMethod属性类的CacheDuration属性来在服务器上允许高速缓冲。下面的代码示例显示如何在XML Web服务方法上使用CacheDuration属性来指定输出高速缓冲为60秒。

[C#]
<%@ WebService Language="C#" Class="MathService" %>
using System;
using System.Web.Services;
public class MathService : WebService {
[WebMethod(CacheDuration=60)]
public float Add(float a, float b)
{
return a + b;
}
[WebMethod(CacheDuration=60)]
public float Subtract(float a, float b)
{
return a - b;
}
[WebMethod(CacheDuration=60)]
public float Multiply(float a, float b)
{
return a * b;
}
[WebMethod(CacheDuration=60)]
public float Divide(float a, float b)
{
if (b==0) return -1;
return a / b;
}
}
[Visual Basic]
<%@ WebService Language="VB" Class="MathService" %>
Imports System
Imports System.Web.Services
Public Class MathService
Inherits WebService
<WebMethod(CacheDuration := 60)> _
Public Function Add(a As Single, b As Single) As Single
Return a + b
End Function

<WebMethod(CacheDuration := 60)> _
Public Function Subtract(a As Single, b As Single) As Single
Return a - b
End Function

<WebMethod(CacheDuration :