TypeError：无法读取 angularJS 中未定义的属性“名称”

Question

当有人忘记输入组名时，我想显示一条错误消息。所以我为输入标签创建了一个 group.name 模型。调用 createGroup 函数时检查条件（提交表单时）。但它给 “TypeError: Cannot read property 'name' of undefined”在读取名称属性时。

          <form name="serverGroup" role="form" ng-model="group" ng-submit="createGroup(group)">
                <div class="form-group createGrpField">
                    <label for="groupname" class="nameField">Name</label>
                    <input id="nameField" type="text" ng-model="group.name" class="form-control" placeholder="Enter group name" />
                </div>

                <div class="createServerPadding">
                    <button id="saveBtn" class="btn btn-default btn-primary" type="submit">Save</button>
                    <button class="btn btn-default" type="cancel">Cancel</button>
                </div>
            </form>

控制器

 $scope.createGroup = function(group) {
        selectedRows = $scope.gridApi.selection.getSelectedRows();

        $scope.emptyName = false
        $scope.selectServer = false;

        if (!group.name || !group) {
            console.log("group", group);
            $scope.emptyName = true;
            $scope.selectServer = false;
         }
  }

Answer 1

使用angular.isDefined();检查其在此处定义的范围是否为DOC

if ( angular.isDefined(group) && group.hasOwnProperty('name') ) {
    console.log("group", group);
    $scope.emptyName = true;
    $scope.selectServer = false;
 }