JS :: get and set caret position inside input box

js caret position.js

function getCaretPosition (ctrl) {
    var caretPos = 0;    
    // IE
    if (document.selection) {
        ctrl.focus ();
        var sel = document.selection.createRange();
        sel.moveStart ('character', -ctrl.value.length);
        caretPos = sel.text.length;
    }
    // Firefox
    else if (ctrl.selectionStart || ctrl.selectionStart == '0'){
        caretPos = ctrl.selectionStart;
    }
    return caretPos;
}

function setCaretPosition (ctrl, pos){
    if(ctrl.setSelectionRange) {
        ctrl.focus();
        ctrl.setSelectionRange(pos,pos);
    }
  else if (ctrl.createTextRange) {
        var range = ctrl.createTextRange();
        range.collapse(true);
        range.moveEnd('character', pos);
        range.moveStart('character', pos);
        range.select();
    }
}