小编Est*_*sti的帖子

我是ReactJS的新手.当我点击它时,我试图同时更改文本和按钮的颜色.此代码有效:

class ToggleHelp extends React.Component {
  constructor(props) {
    super(props);
    this.state = {isHelpOn: true};

    // This binding is necessary to make `this` work in the callback
    this.handleClick = this.handleClick.bind(this);
  }

  handleClick() {
    this.setState(prevState => ({
      isHelpOn: !prevState.isHelpOn
    }));
  }

  render() {
    return (
      <button onClick={this.handleClick}>
        {this.state.isHelpOn ? 'HELP ON' : 'HELP OFF'}
      </button>
    );
  }
}

ReactDOM.render(
  <ToggleHelp />,
  document.getElementById('root')
);

但是,当我尝试使用如下所示的内联样式时,代码停止工作.

<button style={background:yellow} onClick={this.handleClick}>
  {this.state.isHelpOn ? 'HELP ON' : 'HELP OFF'}
</button>

我已经尝试了几次,以各种方式做到这一点.我希望它能成为当下的内联风格.是否可以直接从React应用内联样式？如果是,那么想法是评估状态并通过条件语句在另一种颜色上设置一种颜色.

我是Clojure的新手,我有一个关于嵌套doseq循环的问题.

我想迭代一个序列并得到一个子序列,然后得到一些键来在所有序列元素上应用一个函数.

给定的序列具有或多或少的结构,但有数百本书籍,书架和许多库:

([:state/libraries {6 #:library {:name "MUNICIPAL LIBRARY OF X" :id 6 
:shelves {3 #:shelf {:name "GREEN SHELF" :id 3 :books  
{45 #:book {:id 45 :name "NECRONOMICON" :pages {...}, 
{89 #:book {:id 89 :name "HOLY BIBLE" :pages {...}}}}}}}}])

这是我的代码:

(defn my-function []   (let [conn  (d/connect (-> my-system :config :datomic-uri))]
(doseq [library-seq (read-string (slurp "given-sequence.edn"))]
  (doseq [shelves-seq (val library-seq)]
    (library/create-shelf conn {:id (:shelf/id (val shelves-seq)) 
                                :name (:shelf/name (val shelves-seq))})
    (doseq [books-seq (:shelf/books (val shelves-seq))]
      (library/create-book conn (:shelf/id (val shelves-seq)) {:id …