JS traversal array duplicate values and objects duplicate values in a group

Array to remove duplicate values:

The Arr.indexof () method returns the position of the first occurrence of a specified string value in the second character,  or 1 if none is present in the array.

var arr=[2,8,5,0,5,2,6,7,2];function unique1 (arr) {  var result=[];  for (var i = 0; i < arr.length; i++) {     if (Hash.indexof (Arr[i]) ==-1) {      resule.push (arr[i]);     }  }  return result;}

The repetition of object removal in the array is worth the method:
var arr=[
    {ID: "45545", Text: "Admin"},

    {ID: "4556545", Text: "Preview"},

    {ID: "455455", Text: "No Permission"},

     {ID: "45545", Text: "Admin"}

];
Method 1
var result=[];
var obj={};
for (i=0;i<arr.length;i++)
{
   if (!obj[arr[i].id])
    {
       Resule.push (Arr[i]);
       Obj[arr (i). Id]=true;
    }
}
Console.log (Result)

     Method 2: Use the Reduce method to iterate through the array, and reduce the first parameter to traverse the function that needs to be executed, the second parameter is the initial value of item       var obj = {};       arr = arr.Reduce(function (item, next) {           ? ": obj[next.key] = True && Item.push (next);       return item;    }, []);

      
     A different way
    arr = arr.Reduce(function (item, next) {;
               if (!obj[next.key])
                    {
                       Item.push (next);
                       Obj[next.key]=true

                     }       return item;    }, []);

JS traversal array duplicate values and objects duplicate values in a group