How to move an element specified in a JavaScript array to the first bit

Objective: To realize storage search history by Localstrorage--combining Store.js

The code is as follows:

functionaddsearchhistory (key,value) {varOldarr =Store.get (key); if(Oldarr) { for(vari = 0; i < oldarr.length; i++) {            if(Oldarr[i] = = =value) {Oldarr.splice (i,1);//if the element exists in the data group, the element is deleted                 Break; }} oldarr.unshift (value); //add to first position againStore.set (Key,oldarr); } Else {        varNEWARR =NewArray ();        Newarr.unshift (value);    Store.set (Key,newarr); }}

How to move an element specified in a JavaScript array to the first bit