JavaScript 去除数组重复项的简单实现

<!DOCTYPE html>
<html lang="zh-cn">
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<script>
var arr = ["aaa","bbb","aaa","ccc","ddd","ccc"];
function unique(arr) {
  var result = [], hash = {};
  for (var i = 0, elem; (elem = arr[i]) != null; i++) {
    if (!hash[elem]) {
      result.push(elem);
      hash[elem] = true;
    }
  }
  return result;
}
console.info(unique(arr));
</script>
</body>
</html>