JS实现的字符串数组去重功能小结

更新时间：2020-09-01 00:36:01 作者：startmvc

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

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：