If you are using an array and want to use indexOf for them, Just run this code before making any calls in indexOf()
Below code will create a function call .IndexOf if it doesn’t exists.
if (!Array.prototype.indexOf) {
Array.prototype.indexOf = function (elt /*, from*/) {
var len = this.length >>> 0;
var from = Number(arguments[1]) || 0;
from = (from < 0)
? Math.ceil(from)
: Math.floor(from);
if (from < 0)
from += len;
for (; from < len; from++) {
if (from inthis&&
this[from] === elt)
return from;
}
return -1;
};
}