function insert_text(el,ins) {
    if (el.setSelectionRange){
        el.value = el.value.substring(0,el.selectionStart) + ins + el.value.substring(el.selectionStart,el.selectionEnd) + el.value.substring(el.selectionEnd,el.value.length);
    }
    else if (document.selection && document.selection.createRange) {
        el.focus();
        var range = document.selection.createRange();
        range.text = ins + range.text;
    }
}