限制输入减号

Question

我需要限制用户输入minus 符号。如何使用以下 jQuery 我得到？

$("#Age").keydown(function (e) {

            // Allow: backspace, delete, tab, escape, enter  
            if ($(this).val().length <= 2 || $.inArray(e.keyCode, [46, 8, 9, 27, 13, 110]) !== -1 ||              
                (e.keyCode >= 35 && e.keyCode <= 39)) {
                // let it happen, don't do anything
                return;
            }
            else {
                event.preventDefault();
            }
            // Ensure that it is a number and stop the keypress
            if ($(this).val().length <= 2 || (e.shiftKey || (e.keyCode < 48 || e.keyCode > 57)) && (e.keyCode < 96 || e.keyCode > 105)) {
                e.preventDefault();
            }
            else {
                event.preventDefault();
            }
        });
    }); // end of $

Answer 1

ASCII key codes

减号 ASCII 值为 45

$("#Age").keydown(function (e) {
  if (e.keyCode != 45) { //it does't allow user to enter minus(-) symbol
    ..
  }
  else {
    event.preventDefault();
  }
}); // end of $