XZ_iOS之网页去广告

// 方法一：

 - (void)showNews:(NSDictionary *)news

 {

 // 1.取出网页内容

 NSString *body = news[@"body"];

 

 // 2.取出图片

 NSDictionary *img = [news[@"img"] lastObject];

 NSString *imgHTML = [NSString stringWithFormat:@"<img src=\"%@\" width=\"300\" height=\"171\">", img[@"src"]];

 

 // 2.创建一个webView，显示网页

 UIWebView *webView = [[UIWebView alloc] init];

 webView.frame = self.view.bounds;

 [self.view addSubview:webView];

 

 // 3.拼接网页内容

 NSString *html = [body stringByReplacingOccurrencesOfString:img[@"ref"] withString:imgHTML];

 

 // 4.取出新闻标题

 NSString *title = news[@"title"];

 // 5.取出新闻的时间

 NSString *time = news[@"ptime"];

 

 // 头部内容

 NSString *header = [NSString stringWithFormat:@"<div class=\"title\">%@</div><div class=\"time\">%@</div>", title, time];

 html = [NSString stringWithFormat:@"%@%@", header, html];

 

 // 链接mainBundle中的CSS文件

 NSURL *cssURL = [[NSBundle mainBundle] URLForResource:@"news" withExtension:@"css"];

 html = [NSString stringWithFormat:@"%@<link rel=\"stylesheet\" href=\"%@\">", html, cssURL];

 

 // 5.加载网页内容

 [webView loadHTMLString:html baseURL:nil];

 }

 

// 方法二：火狐浏览器：在要去掉的广告上，右键”查看元素“，将代码粘贴到要替换的字符串处

 NSString *url = @"http://ibaby.ipadown.com/api/food/food.show.detail.php?id=";

    NSString *webSite = [url stringByAppendingString:self.Idtext];

    NSURL *siteURL= [NSURL URLWithString:webSite];

    NSURLRequest *request = [NSURLRequest requestWithURL:siteURL];

    // 加载请求

//    [self.webView.web loadRequest:request];

    dispatch_async(dispatch_get_global_queue(0, 0), ^{

        NSURLSessionDataTask *dataTask = [[NSURLSession sharedSession]dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {

 

            self.htmlAbosluteString = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding];

            self.htmlAbosluteString = [self.htmlAbosluteString stringByReplacingOccurrencesOfString:@"<img width=\"0\" height=\"0\" style=\"width: 803px; height: 121px;\" src=\"http://ubmcmm.baidustatic.com/media/v1/0f0007y3CMO4YsUwoxXbB6.jpg\"></img>" withString:@""];

// 这是要去掉广告的第二个地方

self.htmlAbosluteString = [self.htmlAbosluteString stringByReplacingOccurrencesOfString:str9 withString:@""];

            dispatch_async(dispatch_get_main_queue(), ^{

                [self.webView.web loadHTMLString:self.htmlAbosluteString baseURL:nil];

            });

        }];

        [dataTask resume];

        CGRect tmpFrame = self.webView.web.frame;

        CGFloat h = self.navigationController.navigationBar.frame.size.height + 20;

        tmpFrame.origin.y -= h;

        self.webView.web.frame = tmpFrame;

    });

// 方法三：

 NSString *str = @".jpg\" height=\"200\" width=\"340\"/>";

- (NSString *)transformMessage:(NSString *)message withString:(NSString *)string

{

    NSString *messageCopy = message;

    NSScanner *theScanner;

    NSString *text = nil;

    theScanner = [NSScanner scannerWithString:messageCopy];

    while ([theScanner isAtEnd] == NO)

    {

         // find start of tag

        [theScanner scanUpToString:@".jpg" intoString:NULL] ;

         // find end of tag

        if ([theScanner scanUpToString:@">" intoString:&text] || [theScanner scanUpToString:@"/>" intoString:&text]) {

            // .jpg" height="200" width="340"/>

            // 如果不需要第二个参数 ：

            // 可以将string替换为 [NSString stringWithFormat:@".jpg\" height=\\\"200\" width=\"340\"/>"]

            if (text != nil) {

                messageCopy = [messageCopy stringByReplacingOccurrencesOfString:[NSString stringWithFormat:@"%@>", text] withString:string];

                NSLog(@"%@",messageCopy);

                break;

            }

        }

    }

    return messageCopy;

}

作用是把start tag和end tag 之间替换成string的值