我今天在学习 React 时遇到了这行代码：
import React, {Component, PropTypes } from 'react';
class App extends Component {
static propTypes = {
transactions: PropTypes.array,
summary: PropTypes.object,
gridFields: PropTypes.array,
actions: PropTypes.object
};
componentWillMount() {
const { transactions, actions } = this.props;
actions.requestSum(transactions);
}
render() {
const {
transactions,
gridFields,
summary,
actions
} = this.props;
return (
<div className="viewport">
<Header addTodo={actions.addTodo} />
<Grid fields={gridFields} data={transactions}>
<TransactionForm action={actions.addTransaction}/>
<TransactionSummary data={summary} fields={gridFields} />
</Grid>
</div>
);
}
}
}
但是是什么const {transactions, actions} = this.props意思呢？我习惯了这样的事情：
const myVariable = 3;
React 如何知道在事务和动作中存储什么？
这个解构语句
const {transactions, actions} = this.props;
类似于下面的意思：
const transactions = this.props.transactions,
actions = this.props.actions;
如需更多解构理解，请访问此处：https : //developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment
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我来说两句