Issue Type: - [x] Bug - [ ] Feature - [ ] Help Version & Environment: [在线demo](https://stackblitz.com/edit/angular-ifbork) Description: select 选择器在选择 0 (number 类型) 时没有触发 (modelChange) 事件，导致这个问题的代码可能是 [L116](https://github.com/ElemeFE/element-angular/blob/master/src/select/select.ts#L116)
Issue Type:
Version & Environment:
在线demo
Description:
select 选择器在选择 0 (number 类型) 时没有触发 (modelChange) 事件，导致这个问题的代码可能是 L116