JS实现的字符串数组去重功能小结

本文实例讲述了JS实现的字符串数组去重功能。分享给大家供大家参考，具体如下：

这里只考虑最简单字符串的数组去重，暂不考虑，对象，函数，NaN等情况，这种用正则实现起来就吃力不讨好了。

非正则实现：ES6实现

<script>
let str_arr=["b","c",1,"a", 3,"v", "2","e", "6","g", "9", "arr",9, "hello",",6", "9", "1", 2, 6, "b", "c"]
function unique(arr){
 return [...new Set(arr)]
}
console.log(unique(str_arr)) 
</script>

运行结果：

ES5实现

<script>
var str_arr = ["b","c",1,"a", 3,"v", "2","e", "6","g", "9", "arr",9, "hello",",6", "9", "1", 2, 6, "b", "c"]
  function unique(arr) {
    return arr.filter(function(ele, index, array) {
      return array.indexOf(ele) === index
    })
  }
  console.log(unique(str_arr))
</script>

运行结果同上

ES3实现

<script>
var str_arr = ["b","c",1,"a", 3,"v", "2","e", "6","g", "9", "arr",9, "hello",",6", "9", "1", 2, 6, "b", "c"]
function unique(arr) {
  var obj = {},
    array = []
  for (var i = 0, len = arr.length; i < len; i++) {
    var key = arr[i] + typeof arr[i]
    if (!obj[key]) {
      obj[key] = true
      array.push(arr[i])
    }
  }
  return array
}
console.log(unique(str_arr))
</script>

运行结果同上

用正则实现

<script>
 var str_arr = ["b","c",1,"a", 3,"v", "2","e", "6","g", "9", "arr",9, "hello",",6", "9", "1", 2, 6, "b", "c"]
 function unique(arr) {
   return arr.sort().join(",,").
   replace(/(,|^)([^,]+)(,,\2)+(,|$)/g, "$1$2$4").
   replace(/,,+/g, ",").
   replace(/,$/, "").
   split(",")
 }
 console.log(unique(str_arr))
</script>

运行结果：

感兴趣的朋友可以使用在线HTML/CSS/JavaScript代码运行工具：http://tools.3water.com/code/HtmlJsRun测试上述代码运行效果。