function checkEmail(field) {
      var email = document.getElementById(field);
      var filter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
      if (!filter.test(email.value)) {
            return false;
      }
      return true;
}

$(document).ready(
      function() {
            
            var errorMessages = {
                  name: 'Please check your name',
                  email: 'Please check your E-Mail'
            }
            
            $('#contactform').submit(
                  function() {
                        var errorcode =0;
                        $('#errormessage').hide().empty();
                        
                        $('#contactform .required').removeClass('error');
                        
                        if($('#contactform #name').val() == '') {
                              $('#contactform #name').addClass('error');
                              $('#errormessage').show().append('<p>'+errorMessages.name+'</p>');
                              errorcode = 1;
                        }
                              
                        if($('#contactform #email').val() == '' || ! checkEmail('email')) {
                              $('#contactform #email').addClass('error');
                              $('#errormessage').show().append('<p>'+errorMessages.email+'</p>');
                              errorcode = 1;
                        }
                        
                        if (errorcode == 0) {
                              return true;
                        } else {
                              return false;
                        }     
                  }
            );                      
      }
);