我正在阅读reactjs文档的Forms部分,并尝试使用此代码来演示用法(JSBIN).onChange
var React= require('react');
var ControlledForm= React.createClass({
getInitialState: function() {
return {
value: "initial value"
};
},
handleChange: function(event) {
console.log(this.state.value);
this.setState({value: event.target.value});
console.log(this.state.value);
},
render: function() {
return (
<input type="text" value={this.state.value} onChange={this.handleChange}/>
);
}
});
React.render(
<ControlledForm/>,
document.getElementById('mount')
);
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当我<input/>在浏览器中更新值时,回调console.log内的第二个handleChange打印与value第一个相同console.log,为什么我看不到回调this.setState({value: event.target.value})范围内的结果handleChange?
我想问一下当我做onclick事件时为什么我的状态没有改变.我刚才搜索过我需要在构造函数中绑定onclick函数,但状态仍未更新.这是我的代码:
import React from 'react';
import Grid from 'react-bootstrap/lib/Grid';
import Row from 'react-bootstrap/lib/Row';
import Col from 'react-bootstrap/lib/Col';
import BoardAddModal from 'components/board/BoardAddModal.jsx';
import style from 'styles/boarditem.css';
class BoardAdd extends React.Component {
constructor(props){
super(props);
this.state = {
boardAddModalShow: false
}
this.openAddBoardModal = this.openAddBoardModal.bind(this);
}
openAddBoardModal(){
this.setState({ boardAddModalShow: true });
// After setting a new state it still return a false value
console.log(this.state.boardAddModalShow);
}
render() {
return (
<Col lg={3}>
<a href="javascript:;" className={style.boardItemAdd} onClick={this.openAddBoardModal}>
<div className={[style.boardItemContainer,style.boardItemGray].join(' ')}>
Create New Board
</div>
</a>
</Col> …Run Code Online (Sandbox Code Playgroud)