檢查專案中是否自定義了UserAgent請求頭

解決方法：保留原來的請求頭

UIWebView *webView2 = [[UIWebView alloc] init];
NSString *oldAgent = [webView2 stringByEvaluatingJavaScriptFromString: @"navigator.userAgent"];
NSString *newAgent = [NSString stringWithFormat: @"%@;%@", oldAgent, @"vic-higher-ios"];
NSDictionary *dictionary = [NSDictionary dictionaryWithObjectsAndKeys:newAgent, @"UserAgent", nil];
[[NSUserDefaults standardUserDefaults] registerDefaults: dictionary];