后臺更新了URL的內容之后，在沒有刪除app的情況下直接進行了安裝，導致出現了網頁內容不更新的情況，在刪除了原來的APP，重新打包之后，情況恢復，懷疑是自己寫的webview沒有添加清除緩存功能造成，下面是清除緩存的代碼：

- (void)leftBarButtonAction : (UIBarButtonItem *)sender {
    [self.baseButton removeFromSuperview];
    _baseWebView = nil;
    [self cleanCacheAndCookie];
    [self.navigationController popViewControllerAnimated:YES];
}

- (void)cleanCacheAndCookie{
    //清除cookies
    NSHTTPCookie *cookie;
    NSHTTPCookieStorage *storage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
    for (cookie in [storage cookies]){
        [storage deleteCookie:cookie];
    }
    //清除UIWebView的緩存
    [[NSURLCache sharedURLCache] removeAllCachedResponses];
    NSURLCache * cache = [NSURLCache sharedURLCache];
    [cache removeAllCachedResponses];
    [cache setDiskCapacity:0];
    [cache setMemoryCapacity:0];
} 

或者加載的時候直接禁止緩存

request = [NSURLRequest requestWithURL:url  cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:10];