如何通过js获取网页中所有图片并加入点击事件,实现

JavaScript020

如何通过js获取网页中所有图片并加入点击事件,实现,第1张

在网页加载完成时,通过js获取图片和添加点击的识别方式

- (void)webViewDidFinishLoad:(UIWebView *)webView {

[IDProgressHUD IDPlaceViewHideDirect:self.view]

//这里是js,主要目的实现对url的获取

static NSString * const jsGetImages =

@"function getImages(){\

var objs = document.getElementsByTagName(\"img\")\

var imgScr = ''\

for(var i=0i<objs.lengthi++){\

imgScr = imgScr + objs[i].src + '+'\

}\

return imgScr\

}"

[webView stringByEvaluatingJavaScriptFromString:jsGetImages]//注入js方法

NSString *urlResurlt = [webView stringByEvaluatingJavaScriptFromString:@"getImages()"]

mUrlArray = [NSMutableArray arrayWithArray:[urlResurlt componentsSeparatedByString:@"+"]]

if (mUrlArray.count >= 2) {

[mUrlArray removeLastObject]

}

//urlResurlt 就是获取到得所有图片的url的拼接;mUrlArray就是所有Url的数组

//添加图片可点击js

[mWebView stringByEvaluatingJavaScriptFromString:@"function registerImageClickAction(){\

var imgs=document.getElementsByTagName('img')\

var length=imgs.length\

for(var i=0i<lengthi++){\

img=imgs[i]\

img.onclick=function(){\

window.location.href='image-preview:'+this.src}\

}\

}"]

[mWebView stringByEvaluatingJavaScriptFromString:@"registerImageClickAction()"]

}

//在这个方法中捕获到图片的点击事件和被点击图片的url

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType {

//预览图片

if ([request.URL.scheme isEqualToString:@"image-preview"]) {

NSString* path = [request.URL.absoluteString substringFromIndex:[@"image-preview:" length]]

path = [path stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]

//path 就是被点击图片的url

return NO

}

return YES

}

var imgs = document.getElementsByTagName("img")var imgURLs=new Array(imgs.length)for(var i = 0i<imgs.lengthi++){ imgURLs[i] = imgs[i].src//如果用document.getElementsByTagName("img")[i].src每取一个图片地址就会对全部图片查找一次,这样效率比较低,还是储存在imgs中比较好!}//以上代码最好放在页面的最后面,或window.onload事件里,这样就不会因为页面没有全部加载完而没有全部读取到img元素使用js获取页面中所有的图片地址