Add example.

README.md

@@ -29,6 +29,54 @@ $ npm run build # 编译
 $ npm run watch # 开发模式
 ```
 
+## React中使用
+
+[react-hotkeys](https://github.com/jaywcjlove/react-hotkeys)，安装如下：
+
+```sh
+npm i -S react-hot-keys
+```
+
+例子
+
+```js
+import React, { Component } from 'react';
+import Hotkeys from 'react-hot-keys';
+
+export default class HotkeysDemo extends Component {
+  constructor(props) {
+    super(props);
+    this.state = {
+      output: 'Hello, I am a component that listens to keydown and keyup of a',
+    }
+  }
+  onKeyUp(keyName, e, handle) {
+    console.log("test:onKeyUp", e, handle)
+    this.setState({
+      output: `onKeyUp ${keyName}`,
+    });
+  }
+  onKeyDown(keyName, e, handle) {
+    console.log("test:onKeyDown", keyName, e, handle)
+    this.setState({
+      output: `onKeyDown ${keyName}`,
+    });
+  }
+  render() {
+    return (
+      <Hotkeys 
+        keyName="shift+a,alt+s" 
+        onKeyDown={this.onKeyDown.bind(this)}
+        onKeyUp={this.onKeyUp.bind(this)}
+      >
+        <div style={{ padding: "50px" }}>
+          {this.state.output}
+        </div>
+      </Hotkeys>
+    )
+  }
+}
+```
 
 ## 使用