Get cursor position (in characters) within a text Input field

Question

How can I get the caret position from within an input field?

I have found a few bits and pieces via Google, but nothing bullet proof.

Basically something lik

Answer 1

Perhaps you need a selected range in addition to cursor position. Here is a simple function, you don't even need jQuery:

function caretPosition(input) {
    var start = input[0].selectionStart,
        end = input[0].selectionEnd,
        diff = end - start;

    if (start >= 0 && start == end) {
        // do cursor position actions, example:
        console.log('Cursor Position: ' + start);
    } else if (start >= 0) {
        // do ranged select actions, example:
        console.log('Cursor Position: ' + start + ' to ' + end + ' (' + diff + ' selected chars)');
    }
}

Let's say you wanna call it on an input whenever it changes or mouse moves cursor position (in this case we are using jQuery .on()). For performance reasons, it may be a good idea to add setTimeout() or something like Underscores _debounce() if events are pouring in:

$('input[type="text"]').on('keyup mouseup mouseleave', function() {
    caretPosition($(this));
});

Here is a fiddle if you wanna try it out: https://jsfiddle.net/Dhaupin/91189tq7/