In this post i will show you how to remove duplicates from array in javascript.
1. We can use filter()
method to remove duplicates from array , if the index of the element gets matched with the indexOf value then only that element will get added.
let data = [1, 2, 3, 2, 1];
let uniqueData = data.filter((c, index) => {
return data.indexOf(c) == index;
});
console.log(uniqueData);
Output - [ 1, 2, 3 ]
2. Using we can remove duplicate from array , Set
is nothing but a collection of unique data , we used set to convert the array into Set to remove the duplicates, then using spread operator we have converted back the Set into array again.
let data = [1, 2, 3, 2, 1];
let setData= new Set(data);
let uniqueData = [... setData]
console.log(uniqueData);
Output - [ 1, 2, 3 ]
3. Another way to remove duplicate from array . using forEach and includes method.
array.includes(element) if the element if there in the array the include
method will return true
else false
. so below example we are iterating the data array using forEach loop and inside of it we are checking if() uniqueData array is having each the data element or not , if not then we are pushing that element to the uniqueData array.
let data = [1, 2, 3, 2, 1];
let uniqueData=[];
data.forEach(elem=>{
if(!uniqueData.includes(elem)){
uniqueData.push(elem);
}
})
console.log(uniqueData);
Output - [ 1, 2, 3 ]
You can choose any of the three examples to remove duplicate from array in your project.
I hope this article is helpful for you , i am very glad to help you thanks for reading