jQuery Command for form

jQuery Command for form.md

Type in one input field and show in other input field realtime. Also replace non alpha numeric with empty space and replace space with underscore.

$('body').on('keyup', '.input-label', function(event) {
     var me = $(this);
     var valOfme = me.val();   
     valOfme = valOfme.replace(/[^a-zA-Z 0-9]+/g,'').replace(/\s+/g,'_');
     me.closest('tr').find('input.input-field').val(valOfme);   
});

Allow only alhpa numeric and underscore, backspace or delete key

$('body').on('keypress', '.input-field', function (e) {   
  var keycode =  e.keyCode ? e.keyCode : e.which;
  if (keycode != 8 && keycode != 46) {        
    var regex = new RegExp("^[a-zA-Z0-9_]+$");
    var str = String.fromCharCode(!e.charCode ? e.which : e.charCode);
    if (regex.test(str)) {
        return true;
    }

    e.preventDefault();
    return false;
  }
});