64 lines
1.3 KiB
Markdown
64 lines
1.3 KiB
Markdown
---
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title: Use State to Toggle an Element
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localeTitle: 使用State切换元素
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---
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## 使用State切换元素
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* 您可以通过检查和更改其状态来切换元素。
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## 提示1：
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* 记住要结合`this`的方法构造。
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```javascript
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this.toggleVisibility = this.toggleVisibility.bind(this);
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```
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## 提示2：
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* 请记住，您可以使用JavaScript函数来检查元素的状态。
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## 解：
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```jsx
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class MyComponent extends React.Component {
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constructor(props) {
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super(props);
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this.state = {
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visibility: false
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};
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// change code below this line
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this.toggleVisibility = this.toggleVisibility.bind(this);
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// change code above this line
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}
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// change code below this line
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toggleVisibility() {
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if (this.state.visibility == true) {
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this.setState({
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visibility: false
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});} else {
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this.setState({
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visibility: true
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})
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}
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}
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// change code above this line
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render() {
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if (this.state.visibility) {
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return (
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<div>
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<button onClick={this.toggleVisibility}>Click Me</button>
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<h1>Now you see me!</h1>
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</div>
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);
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} else {
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return (
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<div>
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<button onClick={this.toggleVisibility}>Click Me</button>
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</div>
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);
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}
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}
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};
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``` |