Question

尝试通过以下方法与JavaScript中的数组进行比较。

componentDidMount () {
    this.props.onInitIngredients();
}


//Some Code...


const mapStateToProps = state => {
    return {
        ings: state.ingredients,
        price: state.totalPrice,
        error: state.error
    }
};

const mapDispatchToProps = dispatch => {
    return {
        onIngredientAdded: (ingName) => dispatch(burgerbuilderActions.addIngredient(ingName)),
        onIngredientRemoved: (ingName) => dispatch(burgerbuilderActions.removeIngredient(ingName)),
        onInitIngredients: () => dispatch(burgerbuilderActions.initIngredients())
    }
};

export default connect(mapStateToProps, mapDispatchToProps)(withErrorHandler(BurgerBuilder, axios));

我想让它工作，但是如果数组相同，它将返回undefined而不是true或false。

这是完整的代码：

import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';
import {Provider} from 'react-redux';
import {createStore, applyMiddleware, compose} from 'redux';
import {BrowserRouter} from 'react-router-dom';
import thunk from 'redux-thunk';
import burgerBuilderReducer from './store/reducers/burgerBuilder';

const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION__ || compose;

const store = createStore(burgerBuilderReducer, composeEnhancers(
    applyMiddleware(thunk)
));

const app = (
    <Provider store={store}>
        <BrowserRouter>
            <App/>
        </BrowserRouter>
    </Provider>
);

使用类似方法来修复我比较数组的方式的任何帮助将不胜感激。

Answer 1

以下是我用来比较 JS 中两个数组的一些方法。我通常喜欢的方法是JSON.stringify。

不过，我觉得你的方法是最快的，只是你必须用.every()代替forEach()。

let stack1 = [1, 2, 3, 4];
let stack2 = [1, 2, 3, 4];

console.log('every compare:', stack1.every((v, i) => v === stack2[i]));
// or
console.log('toString compare:', stack1.toString() === stack2.toString());
// or
console.log('JSON compare:', JSON.stringify(stack1) === JSON.stringify(stack2));
// or
console.log('short compare:', stack1+'' === stack2+'');

比较两个JS数组的内容

1 个答案: