HttpResponse.AddCacheDependency(CacheDependency[]) 方法

  • 参考

定义

命名空间:
System.Web
程序集:
System.Web.dll

将一组缓存依赖项与响应关联，这样，如果响应存储在输出缓存中并且指定的依赖项发生变化，就可以使该响应失效。

public:
 void AddCacheDependency(... cli::array <System::Web::Caching::CacheDependency ^> ^ dependencies);
public void AddCacheDependency (params System.Web.Caching.CacheDependency[] dependencies);
member this.AddCacheDependency : System.Web.Caching.CacheDependency[] -> unit
Public Sub AddCacheDependency (ParamArray dependencies As CacheDependency())

参数

dependencies
CacheDependency[]

要添加到应用程序依赖项列表的文件、缓存键或 CacheDependency。

例外

ArgumentNullException

dependencies 参数为 null。

InvalidOperationException

在缓存处理管线中调用此方法太迟，已经在创建了缓存响应之后。

示例

以下示例演示如何使用 AddCacheDependency 方法和 CacheDependency 对象创建缓存依赖项。

<%@ Page Language="C#" %>
<%@ outputcache duration="30" varybyparam="none" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="Server">
    private void Page_Load(object sender, System.EventArgs e)
    {
        // Create a Cache Dependency 
        // using a CacheDependency object.
        CacheDependency authorsDependency = new CacheDependency("authors.xml");


        // Make the page invalid if either of the
        // cached items change or expire.        
        Response.AddCacheDependency(authorsDependency);

        // Display the current time for cache reference
        lblOutputCacheMsg.Text = DateTime.Now.ToString();
    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>Cache Dependencies</title> 
</head>
<body>
    <form id="Form1" method="post" runat="server">
        <table>
            <tbody>
                <tr>
                    <td style="WIDTH: 118px">
                        The page was generated at:</td>
                    <td>
                        <asp:Label id="lblOutputCacheMsg" runat="server"></asp:Label>
                    </td>
                </tr>
            </tbody>
        </table>
    </form>
</body>
</html>

<%@ Page Language="VB" %>
<%@ outputcache duration="30" varybyparam="none" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="Server">
    Sub Page_Load()
        ' Create a Cache Dependency 
        ' using a CacheDependency object.
        Dim authorsDependency("authors.xml") As CacheDependency

        ' Make the page invalid if either of the
        ' cached items change or expire.        
        Response.AddCacheDependency(authorsDependency)

        ' Display the current time for cache reference
        lblOutputCacheMsg.Text = DateTime.Now.ToString()
        
        
    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>Cache Dependencies</title> 
</head>
<body>
    <form id="Form1" method="post" runat="server">
        <table>
            <tbody>
                <tr>
                    <td style="WIDTH: 118px">
                        The page was generated at:</td>
                    <td>
                        <asp:Label id="lblOutputCacheMsg" runat="server"></asp:Label>
                    </td>
                </tr>
            </tbody>
        </table>
    </form>
</body>
</html>

注解

方法 AddCacheDependency 允许在缓存的响应和 CacheDependency 对象之间创建依赖项。

适用于

另请参阅