JS实现数组去重,显示重复元素及个数的方法示例

<script>
var arr = ['土豆','土豆','茄子','土豆','茄子','土豆','紫红色'];
function qc(arr){
    var resultObj = {};
    var result = [];
    var result2 = [];
    for(var i=0; i<arr.length; i++){
      if(result.indexOf(arr[i]) == -1){
        result.push(arr[i]);
      }else{
      if(result2.indexOf(arr[i]) == -1){
        result2.push(arr[i]);
      }
      }
    }
    var obj = {}
    arr.forEach((v,k)=>{
      if(obj[v]){
        obj[v]++;
      }else{
        obj[v] = 1;
      }
    });
    resultObj.result = result;
    resultObj.result2 = result2;
    resultObj.obj = obj;
    return resultObj
}
console.log(qc(arr));
</script>

<script>
var a=[1,2,3,4,5,3,5,42,0,2,3,0]
function qc(arr){
    var result=[];
    for(var i=0; i<arr.length; i++){
      for(var j=i+1;j<arr.length;j++){
        if(arr[i] === arr[j]){
          j=++i
        }
      }
      result.push(arr[i])
    }
    document.write(result)
}
qc(a);
</script>