<defaultFtpCachePolicy> Element (Network Settings)

项目
12/08/2006

Describes whether FTP caching is active and describes the default caching policy.

< defaultFtpCachePolicy
  policyLevel="BypassCache|Default|CacheOnly|CacheIfAvailable|Revalidate|Reload|NoCacheNoStore|Revalidate"
/>

Attributes and Elements

The following sections describe attributes, child elements, and parent elements.

Attributes

Attribute	Description
policyLevel	Specifies the FTP caching policy. The default value is Default.

policyLevel Attribute

Value	Description
Default	Returns the cached resource if the resource is fresh, the content length is accurate, and the expiration, modification, and content length attributes are present.
BypassCache	Returns the resource from the server.
CacheOnly	Returns the cached resource if the content length is present and matches the entry size.
CacheIfAvailable	Returns the cached resource if the content length is provided and matches the entry size; otherwise, the resource is downloaded from the server and is returned to the caller.
Revalidate	Returns the cached resource if the timestamp of the cached resource is the same as the timestamp of the resource on the server; otherwise, the resource is downloaded from the server, stored in the cache, and returned to the caller.
Reload	Downloads the resource from the server, stores it in the cache, and returns the resource to the caller.
NoCacheNoStore	If a cached resource exists, it is deleted. The resource is downloaded from the server and is returned to the caller.
Revalidate	Satisfies a request by using the cached copy of the resource if the timestamp is the same as the timestamp of the resource on the server; otherwise, the resource is downloaded from the server, presented to the caller, and stored in the cache.

Child Elements

None.

Parent Elements

Element	Description
requestCaching	Controls the caching mechanism for network requests.

Remarks

Example

The following code example shows how to specify an FTP caching policy of NoCacheNoStore.

<configuration>
  <system.net>
    <requestCaching>
      <defaultFtpCachePolicy
        Level="NoCacheNoStore">
      </defaultFtpCachePolicy>
    </requestCaching>
  </system.net>
</configuration>

通过