JSFiddle - React, Tailwind, and code Playground

HTML

<input name="field[0]" />
<select name="field[1]" />

JavaScript

$("input, select").attr('name', function(i, val) {
    return val.replace(/\d+/, function(n) {
        return ++n;
    });
});

alert($("input")[0].name);
alert($("select")[0].name);