javascipt的数组去重
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<input type="button" value="数组去重1" onclick="show()">
<input type="button" value="数组去重2" onclick="run()">
<input type="button" value="数组去重3" onclick="qq()">
<input type="button" value="数组去重4" onclick="spl()">
</body>
</html>
<script type="text/javascript">
//方法一
console.time()
function has(arr,num){
for(var i=0;i<arr.length-1;i++){
if(arr[i]==num){
return true;
}
}
return false;
}
function norepeat(arr){
var newarr=[];
for(var i=0;i<arr.length-1;i++){
if(has(newarr,arr[i])==false){
newarr.push(arr[i]);
}
}
return newarr;
}
function show(){
var arr=[4,6,4,7,3,7,5,8,9,10];
alert(norepeat(arr));
}
console.timeEnd()
//方法二
console.time()
function nore(arr){
var newarr=[];
for(var i=0;i<arr.length;i++){
if(newarr.indexOf(arr[i])<0){
newarr.push(arr[i]);
}
}
return newarr;
}
function run(){
var arr=[4,6,4,7,3,7,5,8,9,10];
alert(nore(arr));
}
console.timeEnd()
//方法三
console.time()
function qq(arr){
var arr=[4,6,4,7,3,7,5,8,9,10];
var arr1=new Set(arr);
arr1=Array.from(arr1);
alert(arr1);
}
console.timeEnd()
//方法四
console.time()
function norepeat1(arr){
for(var i=0;i<arr.length;i++){
for(var j=i+1;j<arr.length;j++){
if(arr[i]==arr[j]){
arr.splice(j,1);
j--;
}
}
}
return arr;
}
function spl(){
var arr=[4,6,4,7,3,7,5,8,9,10];
alert(norepeat1(arr))
}
console.timeEnd()
</script>
