iOS UIWebView和网页的交互(OC中调执行JS)

  UIWebView和网页的交互(OC中调执行JS)
- (void)viewDidLoad
{
[super viewDidLoad];
// 1.webView
UIWebView *webView = [[UIWebView alloc] init];
webView.frame = self.view.bounds;
webView.delegate = self;
// 伸缩页面至填充整个webView
webView.scalesPageToFit = YES;
// 隐藏scrollView
webView.scrollView.hidden = YES;
[self.view addSubview:webView];

// 2.加载网页
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"http://m.dianping.com/tuan/deal/5501525"]];
[webView loadRequest:request];

// 3.创建
UIActivityIndicatorView *loadingView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
[loadingView startAnimating];
loadingView.center = CGPointMake(160, 240);
[self.view addSubview:loadingView];
self.loadingView = loadingView;
}
// 在OC中调用JS
#pragma mark - UIWebViewDelegate
- (void)webViewDidFinishLoad:(UIWebView *)webView
{
NSMutableString *js1 = [NSMutableString string];
// 0.删除顶部的导航条
[js1 appendString:@"var header = document.getElementsByTagName('header')[0];"];
[js1 appendString:@"header.parentNode.removeChild(header);"];

// 1.删除底部的链接
[js1 appendString:@"var footer = document.getElementsByTagName('footer')[0];"];
[js1 appendString:@"footer.parentNode.removeChild(footer);"];
[webView stringByEvaluatingJavaScriptFromString:js1];

dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.25 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
NSMutableString *js2 = [NSMutableString string];
// 2.删除浮动的广告
[js2 appendString:@"var list = document.body.childNodes;"];
[js2 appendString:@"var len = list.length;"];
[js2 appendString:@"var banner = list[len - 1];"];
[js2 appendString:@"banner.parentNode.removeChild(banner);"];
[webView stringByEvaluatingJavaScriptFromString:js2];

// 显示scrollView
webView.scrollView.hidden = NO;

// 删除圈圈
[self.loadingView removeFromSuperview];
});
}
注意： 从网络上获取数据，如果不想看到某种效果，并且网页存放在服务器端，里面的JS和Html代码，没有办法修改，可以在UIWebView的代理方法执行JS代码，去掉不想看到的效果。