javascript - ReactJS:使用alert()从用户那里获取输入

如何使用alert()允许用户输入其名称并将其保存为状态？

到目前为止，这是我尝试过的事情:

render: function() {
    return (
      <div>
        <input type="text" onChange={ this.handleChange } />
        <Button>Save</Button>
      </div>
    );
  }
}

最佳答案

一种选择是使用the prompt() function，它显示一个模式对话框，通过该对话框可以输入和获取用户输入。 prompt()方法还允许您提供自定义问候语，可以将其作为第一个参数传递，如下所示:

    const enteredName = prompt('Please enter your name')

可以通过多种方式将其与您现有的react组件集成-一种方法可能如下:

/* Definition of handleClick in component */
handleClick = (event) => {

    /* call prompt() with custom message to get user input from alert-like dialog */
    const enteredName = prompt('Please enter your name')

    /* update state of this component with data provided by user. store data
       in 'enteredName' state field. calling setState triggers a render of
       this component meaning the enteredName value will be visible via the
       updated render() function below */
    this.setState({ enteredName : enteredName })
}

render: function() {
    return (
      <div>

        {/* For demonstration purposes, this is how you can render data
            previously entered by the user */ }
        <p>Previously entered user name: { this.state.enteredName }</p>

        <input type="text" onChange={ this.handleChange } />
        <input
          type="button"
          value="Alert the text input"
          onClick={this.handleClick}
        />
      </div>
    );
  }
});