iOS清理WebView的缓存

  

    NSHTTPCookie *cookie;  
    NSHTTPCookieStorage *storage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
    for (cookie in [storage cookies]){  
          [storage deleteCookie:cookie];  
    }  

   //清除UIWebView的缓存  
    [[NSURLCache sharedURLCache] removeAllCachedResponses];  
     NSURLCache * cache = [NSURLCache sharedURLCache];  
     [cache removeAllCachedResponses];  
     [cache setDiskCapacity:0];  
     [cache setMemoryCapacity:0];