javascript - Add array value dynamically with a specific index?

createObjectDataadd: function(component, event)
            {
 var index = event.getParam("indexVar");


            console.log(index);

 var RowItemList1 =
            component.get("v.QuotelinitemList"); 
 RowItemList1.push({

            'sobjectType': 'Quote_Line_Item__c',
 'Name':'',
 'Client_P_N__c':
            ''
 });
 RowItemList1.splice(index+1,0,RowItemList1);
            


 // for (var i = index; i             { 
 // RowItemList1.splice(index+1,0,rowli); 
 // } 

            component.set("v.QuotelinitemList", RowItemList1);

            //RowItemList1.splice(index-1,0,RowItemList1);
            
},

Quote_Line_Item__c
is an object. suppose it has three records. Every record has index value. Every record
has button new quote_line_item button which it is pushing a new quote line item record
at end of the array.

My problem is it
adding at the last index.I want to add it on next index where the record new quote line
item button is pressed.

I tried many ways but it
is not coming.

itemprop="text">

class="normal">Answer

For adding
item at specified index in Array, you can use " href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice"
rel="nofollow noreferrer">Array.splice" like below. It takes 3 arguments:
index, number of items to remove from that index, new value(s) to add. So, trick is you
can pass 0 as second argument which means you do not want to delete any
item

data-hide="false" data-console="true" data-babel="false">
class="snippet-code">

let arr =
            [1,2,3,4]


function addItem(item, index) {

            arr.splice(index, 0, item)
}

addItem(10,
            1)
console.log(arr)