如何在React组件中使用switch语句?

我有一个React组件，在组件的渲染方法中，我有这样的东西:

render() {
    return (
        <div>
            <div>
                // removed for brevity
            </div>

           { switch(...) {} }

            <div>
                // removed for brevity
            </div>
        </div>
    );
}

Now the point is that I have two div elements, one at the top and one at the bottom, that are fixed. In the middle I want to have a switch statement, and according to a value in my state I want to render a different component. So basically, I want the two div elements to be fixed always, and just in the middle to render a different component each time. I'm using this to implement a multi-step payment procedure). Though, as is the code currently it doesn't work, as it gives me an error saying that switch is unexpected. Any ideas how to achieve what I want?

当前回答


function Notification({ text, status }) {
  return (
    <div>
      {(() => {
        switch (status) {
          case 'info':
            return <Info text={text} />;
          case 'warning':
            return <Warning text={text} />;
          case 'error':
            return <Error text={text} />;
          default:
            return null;
        }
      })()}
    </div>
  );
}

2020-12-09 03:07:57

其他回答

  const [route, setRoute] = useState(INITIAL_ROUTE)

  return (
    <RouteContext.Provider value={{ route, setRoute }}>
      {(() => {
        switch (route) {
          case Route.Home:
            return <PopupHomePage />
          case Route.App:
            return <PopupAppPage />
          default:
            return null
        }
      })()}
    </RouteContext.Provider>

2023-02-07 22:27:59

下面是一个使用按钮在组件之间切换的完整工作示例

可以按如下方式设置构造函数

constructor(props)
{
    super(props);
    this.state={
        currentView: ''
    }
}

然后您就可以像下面这样渲染组件了

  render() 
{
    const switchView = () => {

    switch(this.state.currentView) 
    {

      case "settings":   return <h2>settings</h2>;
      case "dashboard":   return <h2>dashboard</h2>;

      default:      return <h2>dashboard</h2>
    }
  }

    return (

       <div>

            <button onClick={(e) => this.setState({currentView: "settings"})}>settings</button>
            <button onClick={(e) => this.setState({currentView: "dashboard"})}>dashboard</button>

            <div className="container">
                { switchView() }
            </div>


        </div>
    );
}

}

正如你所看到的，我正在使用一个按钮来切换状态。

2020-02-23 18:26:54

import React from 'react';

import ListView from './ListView';
import TableView from './TableView';

function DataView({
    currView,
    data,
    onSelect,
    onChangeStatus,
    viewTodo,
    editTodo,
    deleteTodo,
}) {
    return (
        <div>
            {(function () {
                switch (currView) {
                    case 'table':
                        return (
                            <TableView
                                todos={data}
                                onSelect={onSelect}
                                onChangeStatus={onChangeStatus}
                                viewTodo={viewTodo}
                                editTodo={editTodo}
                                deleteTodo={deleteTodo}
                            />
                        );

                    case 'list':
                        return (
                            <ListView
                                todos={data}
                                onSelect={onSelect}
                                onChangeStatus={onChangeStatus}
                                viewTodo={viewTodo}
                                editTodo={editTodo}
                                deleteTodo={deleteTodo}
                            />
                        );

                    default:
                        break;
                }
            })()}
        </div>
    );
}

export default DataView;

2021-09-02 12:16:40

一种在渲染块中使用条件操作符表示一种开关的方法:

{(someVar === 1 &&
    <SomeContent/>)
|| (someVar === 2 &&
    <SomeOtherContent />)
|| (this.props.someProp === "something" &&
    <YetSomeOtherContent />)
|| (this.props.someProp === "foo" && this.props.someOtherProp === "bar" &&
    <OtherContentAgain />)
||
    <SomeDefaultContent />
}

应该确保条件严格返回布尔值。

2018-08-07 21:09:29

React组件中的Switch-Case语句可以如下使用:

<div  id="time-list">
{   
    (() => {
        switch (groupByFilterId) {
            case 0:/*Case 0 */
                return (
                    <div>Case 0</div>
                )
               break;
           case 1: /*Case 1 */
           return ( 
            <div>Case 1</div>
            )
            break;
           case 2:/*Case 2 */
           return ( 
            <div>Case 2</div>
            )
            break;
        }
     })()}

      
       
    
    </div>

2021-05-09 12:05:43

如何在React组件中使用switch语句?

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