var arry = [1br 2];
arry [2] / / undefined
is there a way like indexOf to return the index value of the placeholder?
var arry = [1br 2];
arry [2] / / undefined
is there a way like indexOf to return the index value of the placeholder?
var arry = [1,2,,4,5];
for(var i=0;i<arry.length;iPP){
if(arry[i]){
console.log("success");
}else {
console.log(i);
}
}the place where success is printed can also be left empty
arr.findIndex (I = > i=undefined)
only returns the index, found for the first time. If there are more than one, you have to traverse
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