我是ReactJS和JSX的新手,我对下面的代码有一个小问题。

我试图在每个li上添加多个类到className属性:

<li key={index} className={activeClass, data.class, "main-class"}></li>

我的React组件是:

var AccountMainMenu = React.createClass({
  getInitialState: function() {
    return { focused: 0 };
  },

  clicked: function(index) {
    this.setState({ focused: index });
  },

  render: function() {
    var self = this;
    var accountMenuData = [
      {
        name: "My Account",
        icon: "icon-account"
      },
      {
        name: "Messages",
        icon: "icon-message"
      },
      {
        name: "Settings",
        icon: "icon-settings"
      }
    /*{
        name:"Help &amp; Support &nbsp; <span class='font-awesome icon-support'></span>(888) 664.6261",
        listClass:"no-mobile last help-support last"
      }*/
    ];

    return (
      <div className="acc-header-wrapper clearfix">
        <ul className="acc-btns-container">
          {accountMenuData.map(function(data, index) {
            var activeClass = "";

            if (self.state.focused == index) {
              activeClass = "active";
            }

            return (
              <li
                key={index}
                className={activeClass}
                onClick={self.clicked.bind(self, index)}
              >
                <a href="#" className={data.icon}>
                  {data.name}
                </a>
              </li>
            );
          })}
        </ul>
      </div>
    );
  }
});

ReactDOM.render(<AccountMainMenu />, document.getElementById("app-container"));

当前回答

只要添加,我们就可以过滤掉空字符串。

className={[
    'read-more-box',
    this.props.className,
    this.state.isExpanded ? 'open' : 'close',
].filter(x => !!x).join(' ')}

其他回答

如果你想使用双条件css模块总是莫名其妙,所以我建议你遵循这个模式

import styles from "./styles.module.css"

const Conditonal=({large, redColor}) => {
 return(
  <div className={[large && styles.large] + [redColor && styles.color]>
   ...
  </div>
 )
}

export default Conditonal

如果它只是一个有两个类名的条件语句,使用这个

import styles from "./styles.module.css"

const Conditonal=({redColor}) => {
 return(
  <div className={styles.large + [redColor && styles.color]>
   ...
  </div>
 )
}

export default Conditonal

你可以像这样创建一个具有多个类名的元素,我尝试了这两种方式,工作正常…

如果你导入任何css,那么你可以这样做: 方式1:

import React, { Component, PropTypes } from 'react';
import csjs from 'csjs';
import styles from './styles';
import insertCss from 'insert-css';
import classNames from 'classnames';
insertCss(csjs.getCss(styles));
export default class Foo extends Component {
  render() {
    return (
      <div className={[styles.class1, styles.class2].join(' ')}>
        { 'text' }
      </div>
    );
  }
}

方式2:

import React, { Component, PropTypes } from 'react';
import csjs from 'csjs';
import styles from './styles';
import insertCss from 'insert-css';
import classNames from 'classnames';
insertCss(csjs.getCss(styles));
export default class Foo extends Component {
  render() {
    return (
      <div className={styles.class1 + ' ' + styles.class2}>
        { 'text' }
      </div>
    );
  }
}

**

If you applying css as internal : const myStyle = { color: "#fff" }; // React Element using Jsx const myReactElement = ( <h1 style={myStyle} className="myClassName myClassName1"> Hello World! </h1> ); ReactDOM.render(myReactElement, document.getElementById("app")); .myClassName { background-color: #333; padding: 10px; } .myClassName1{ border: 2px solid #000; } <script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.4.0/umd/react.production.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.4.0/umd/react-dom.production.min.js"></script> <div id="app"> </div>

我使用了这个语法

    <div
      className={[
        "d-inline-flex justify-content-center align-items-center ",
        withWrapper && `ft-icon-wrapper ft-icon-wrapper-${size}`,
        wrapperClass,
      ].join(" ")}
    >
      <img
        className={`ft-icon ft-icon-${size} ${iconClass}`}
        alt={id}
        src={icon}
      />
    </div>

对于这个问题,我使用这个util函数:

export function cn(...args: string[]): string{
    return args.filter(Boolean).join(' ');
}

然后这样应用:

<div className={cn(inter.className, styles.planColumns)}>

可以通过https://www.npmjs.com/package/clsx来完成:

https://www.npmjs.com/package/clsx

首先安装它:

npm install --save clsx

然后将它导入到组件文件中:

import clsx from  'clsx';

然后在组件中使用导入的函数:

<div className={ clsx(classes.class1, classes.class2)}>