swift 获取网页中图片地址的正则表达式

func URLRegex(text: String){    do{        let pattern = "\\bhttp?://.*?(jpg|png)"        let dataDetector = try NSRegularExpression(pattern: pattern, options: NSRegularExpressionOptions.CaseInsensitive)        let res = dataDetector.matchesInString(text, options: NSMatchingOptions(rawValue: 0), range: NSMakeRange(0, text.characters.count))        for checkingRes in res        {            let str = (text as NSString).substringWithRange(checkingRes.range)            print(str)            self.dataArray.append(str)        }        print(self.dataArray)         self.collection.reloadData()    }catch    {        print(error)    }}