---
title: Use Array.map() to Dynamically Render Elements
localeTitle: 使用Array.map()动态渲染元素
---
## 使用Array.map()动态渲染元素
## 提示1:
将两个状态定义为JavaScript `object` 。
```javascript
{object: state, object: state}
```
## 提示2:
您需要`.map()`为数组中的每个对象生成一行。
```javascript
this.state.toDoList.map(i =>
{i});
```
## 解:
添加地图功能后,您会注意到它会为您放入列表中的每个项目生成`` 。
```jsx
const textAreaStyles = {
width: 235,
margin: 5
};
class MyToDoList extends React.Component {
constructor(props) {
super(props);
// change code below this line
this.state = {
userInput: '',
toDoList: []
}
// change code above this line
this.handleSubmit = this.handleSubmit.bind(this);
this.handleChange = this.handleChange.bind(this);
}
handleSubmit() {
const itemsArray = this.state.userInput.split(',');
this.setState({
toDoList: itemsArray
});
}
handleChange(e) {
this.setState({
userInput: e.target.value
});
}
render() {
const items = this.state.toDoList.map(i => {i}); // change code here
return (
My "To Do" List:
);
}
};
```