数组去重

 

  <script>
    // 封装一个  去重的函数 unique 独一无二的
    function unique(arr) {
      var newArr = [];
      for (var i = 0; i < arr.length; i++) {
        if (newArr.indexOf(arr[i]) === -1) {
          newArr.push(arr[i]);
        }
      }
      return newArr;
    }
    var demo = unique(["blue", "green", "blue"]);
    console.log(demo);
  </script>