iOS webview 适应屏幕宽

- (void)webViewDidFinishLoad:(UIWebView *)webView {
    
    [webView stringByEvaluatingJavaScriptFromString:[NSString stringWithFormat:@"document.body.style.zoom=%lf",ScreenWidth/webView.scrollView.contentSize.width-0.00001]];
    [webView stringByEvaluatingJavaScriptFromString:@"document.getElementsByTagName('body')[0].style.textAlign = 'center';"];
      
}