我是angularjs的新手，很难验证我的span内容。。我无法在下面的代码中验证邮件。我使用自定义指令创建电子邮件芯片，我需要更改错误格式的芯片颜色。我尝试了ng模式，但遇到了一些问题。

myAngApp.directive("emailTags", [
      function () {
        return {
          require: "ngModel",
          restrict: "EA",
          scope: {
            mailid: "=ngModel",
          },
          template:
            '<div class="mailid">' +
            '<span class="to-id" >To:</span>' +
            '<div class="email" ng-repeat="mail in mailid track by $index">' +
            '<span class="mail-text" ng-pattern="mailpattern">{{ mail }}</span>' +
            '<a ng-show="isEdit" class="mail-remove" ng-click="remove(mail)">x</a>' +
            "</div>" +
            '<input ng-show="isEdit" type="text"name="email" id="mail-input" ng-model="mail" ' +
            'placeholder="sample@mail.com"' +
            'ng-keyup="$event.keyCode == 13? add(mail) : null" ' +
            'ng-keydown="$event.keyCode == 8 ? removelast(mail) : null"/>' +
            "</div>",
          link: function (scope, element, attrs) {
            scope.isEdit = _.has(attrs.$attr, "edit");
            scope.mailpattern = /^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
            console.log(scope.isEdit);
            scope.add = function (mail) {
              if (!_.isArray(scope.mailid)) scope.mailid = [];
              scope.mailid.push(mail);
              scope.mail = "";
            };
            scope.remove = function (mail) {
              scope.mailid = _.without(scope.mailid, mail);
            };
            scope.removelast = function (mail) {
              // console.log(mail);
              if (!mail) {
                var last = scope.mailid.pop();
              }
            };
          },
        };
      },
    ]);