opened
Richard-Choooou
username_0
Please make sure these boxes are checked before submitting your PR, thank you!

* [x] Make sure you follow Element's contributing guide ([中文](https://github.com/ElemeFE/element/blob/master/.github/CONTRIBUTING.zh-CN.md) | [English](https://github.com/ElemeFE/element/blob/master/.github/CONTRIBUTING.en-US.md) | [Español](https://github.com/ElemeFE/element/blob/master/.github/CONTRIBUTING.es.md)).
* [x] Make sure you are merging your commits to `dev` branch.
* [x] Add some descriptions and refer relative issues for you PR.

如果代码里有不合理的地方还望指出
ImagePreview: 创建了新的组件用于图片预览，完成编码、测试用例以及中文文档的编写
issue
created
jikkai
username_1
感谢你的 PR 和新组件的构思。

不过我认为这个组件目前的必要性不是很大，现阶段已经可以通过已有组件自行封装一个的前提下由官方来提供并维护这样一个复合组件不一定合适。或许你可以将基于 element 封装好的组件提交到 [awesome-element](https://github.com/ElementUI/awesome-element) 以此进行社区贡献 😄
comment
created
Richard-Choooou
username_0
在编写组件的过程中学到了很多知识，感谢饿了么官方提供一个这么好的开源项目😄，(〒︿〒)
comment
created
Richard-Choooou
username_0
想请问一下为什么你们用webpack打包commonjs2模块的包后，可以直接通过improt elememt from 'element'引入工程，我也按照你们的配置，配置了一样的webpack，结果打包后引入工程，报

Cannot assign to read only property 'exports' of object '#<Object>'

错误
comment