業(yè)務(wù)需求是獲取到網(wǎng)頁文章里的圖片
這里就用公眾號來舉個例子:
聲明一個wkwebview
lazy var wkwebview:WKWebView = {
return WKWebView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height - 160))
}()
加載
let url = "https://mp.weixin.qq.com/s/eoQsC4bR2KWnvr3HIL6-DA"
//"https://mp.weixin.qq.com/s/JumTmzPMKPzwylC3SDn7MQ"
//"http://www.baidu.com"
let request = URLRequest(url: URL(string: url)!)
self.wkwebview.load(request)
獲取圖片杂腰,這里要聲明一下:頁面load完成跟資源加載完成是不一樣的。所以在didFinish之后立即調(diào)用這個函數(shù)或許是拿不到圖片的咬荷。最后是延時幾秒執(zhí)行。要解決這個問題白群,應(yīng)該需要監(jiān)聽js的window.onload事件盘榨。
func loadWebView(){
//獲取網(wǎng)頁里面積較大的且靠前的圖片,這里有個問題朴译,在WKWebView, didFinish執(zhí)行完實際上是沒法立即拿到網(wǎng)頁內(nèi)的資源的井佑。
let jsStr = "function getImgArr(){const arr=[];const imgs=document.querySelectorAll(\"img\");Array.prototype.forEach.call(imgs,function(el,index){arr.push({src:el.src,index:index,size:el.width*el.height})});arr.sort(function(a,b){return b.size-a.size});return arr}function getBigImg(arr){if(arr.length){if(arr.length>1){return arr[0].index>arr[1].index?arr[1].src:arr[0].src}}};"
self.wkwebview.evaluateJavaScript(jsStr, completionHandler: nil)
self.wkwebview.evaluateJavaScript("getBigImg(getImgArr())") { (result, error) in
print(result ?? "000")
print(error ?? "sure")
if let resultStr = result as? String, resultStr != ""{
if let imageUrl = URL(string: resultStr) {
do{
if let imageData = try? Data(contentsOf: imageUrl) {
self.imgVie.image = UIImage(data: imageData)
}
}catch let error as NSError {
print(error)
}
}
}
}
}