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>