备忘一下

//关闭调用方法的时候网页会放大
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation
{
    NSString *injectionJSString = @"var script = document.createElement('meta');"
                                   "script.name = 'viewport';"
                                   "script.content=\"width=device-width, user-scalable=no\";"
                                   "document.getElementsByTagName('head')[0].appendChild(script);";
    [webView evaluateJavaScript:injectionJSString completionHandler:nil];
}