17.获取链接后缀名

正则写法

var arr = [
  {
    icon: 'https://xxxxxxxx.png'
  },
  {
    icon: 'https://xxxxx/abc.zip'
  }
]；
var sum=[]
arr.forEach((item,index) => {
    var patternFileExtension = /\.([0-9a-z]+)(?:[\?#]|$)/i;
    //获得文件扩展名 
    var fileExtension = (item.icon).match(patternFileExtension);
    if (fileExtension[1] === "png"){
        sum.push('png')
      }else{
        sum.push('zip')
      }
   }); console.log(sum)