---
order: 1
title:
zh-CN: 用户头像
en-US: Avatar
---
## zh-CN
点击上传用户头像，并使用 `beforeUpload` 限制用户上传的图片格式和大小。
> `beforeUpload` 的返回值可以是一个 Promise 以支持异步处理，如服务端校验等：[示例](https://upload-react-component.vercel.app/demo/before-upload#beforeupload)。
## en-US
Click to upload user's avatar, and validate size and format of picture with `beforeUpload` .
> The return value of function `beforeUpload` can be a Promise to check asynchronously. [demo](https://upload-react-component.vercel.app/demo/before-upload#beforeupload)
```jsx
import { Upload, message } from 'antd';
import { LoadingOutlined, PlusOutlined } from '@ant-design/icons';
function getBase64(img, callback) {
const reader = new FileReader();
reader.addEventListener('load', () => callback(reader.result));
reader.readAsDataURL(img);
}
function beforeUpload(file) {
const isJpgOrPng = file.type === 'image/jpeg' || file.type === 'image/png';
if (!isJpgOrPng) {
message.error('You can only upload JPG/PNG file!');
}
const isLt2M = file.size / 1024 / 1024 < 2 ;
if (!isLt2M) {
message.error('Image must smaller than 2MB!');
}
return isJpgOrPng & & isLt2M;
}
class Avatar extends React.Component {
state = {
loading: false,
};
handleChange = info => {
if (info.file.status === 'uploading') {
this.setState({ loading: true });
return;
}
if (info.file.status === 'done') {
// Get this url from response in real world.
getBase64(info.file.originFileObj, imageUrl =>
this.setState({
imageUrl,
loading: false,
}),
);
}
};
render() {
const { loading, imageUrl } = this.state;
const uploadButton = (
< div >
{loading ? < LoadingOutlined / > : < PlusOutlined / > }
< div style = {{ marginTop: 8 } } > Upload< / div >
< / div >
);
return (
< Upload
name="avatar"
listType="picture-card"
className="avatar-uploader"
showUploadList={false}
action="https://www.mocky.io/v2/5cc8019d300000980a055e76"
beforeUpload={beforeUpload}
onChange={this.handleChange}
>
{imageUrl ? < img src = {imageUrl} alt = "avatar" style = {{ width: ' 100 % ' } } / > : uploadButton}
< / Upload >
);
}
}
export default Avatar;
```
