React:将道具传递给功能组件

React: Passing down props to functional components(React:将道具传递给功能组件)

问题描述

我有一个关于道具和功能组件的看似微不足道的问题.基本上，我有一个容器组件，它在用户单击按钮触发的状态更改时呈现模态组件.modal 是一个无状态的功能组件，它包含一些需要连接到容器组件内的功能的输入字段.

I have a seemingly trivial question about props and functional components. Basically, I have a container component which renders a Modal component upon state change which is triggered by user click on a button. The modal is a stateless functional component that houses some input fields which need to connect to functions living inside the container component.

我的问题:当用户与无状态模态组件内的表单字段交互时，如何使用父组件内的函数来更改状态?我是否错误地传递了道具?提前致谢.

My question: How can I use the functions living inside the parent component to change state while the user is interacting with form fields inside the stateless Modal component? Am I passing down props incorrectly? Thanks in advance.

容器

export default class LookupForm extends Component {
    constructor(props) {
        super(props);

        this.state = {
            showModal: false
        };
    }
    render() {
        let close = () => this.setState({ showModal: false });

        return (
            ... // other JSX syntax
            <CreateProfile fields={this.props} show={this.state.showModal} onHide={close} />
        );
    }

    firstNameChange(e) {
      Actions.firstNameChange(e.target.value);
    }
};

功能(模态)组件

const CreateProfile = ({ fields }) => {
  console.log(fields);
  return (
      ... // other JSX syntax

      <Modal.Body>
        <Panel>
          <div className="entry-form">
            <FormGroup>
              <ControlLabel>First Name</ControlLabel>
              <FormControl type="text"
                onChange={fields.firstNameChange} placeholder="Jane"
                />
            </FormGroup>
  );
};

示例:假设我想从 Modal 组件中调用 this.firstNameChange.我猜想将道具传递给功能组件的解构"语法让我有点困惑.即:

Example: say I want to call this.firstNameChange from within the Modal component. I guess the "destructuring" syntax of passing props to a functional component has got me a bit confused. i.e:

const SomeComponent = ({ someProps }) = >{//... };

推荐答案

您需要为需要调用的每个函数单独传递每个 prop

You would need to pass down each prop individually for each function that you needed to call

<CreateProfile
  onFirstNameChange={this.firstNameChange} 
  onHide={close}
  show={this.state.showModal}
/>

然后在 CreateProfile 组件中你可以这样做

and then in the CreateProfile component you can either do

const CreateProfile = ({onFirstNameChange, onHide, show }) => {...}

通过解构，它将匹配的属性名称/值分配给传入的变量.名称只需要与属性匹配

with destructuring it will assign the matching property names/values to the passed in variables. The names just have to match with the properties

或者干脆做

const CreateProfile = (props) => {...}

并在每个地方调用 props.onHide 或您尝试访问的任何道具.

and in each place call props.onHide or whatever prop you are trying to access.

这篇关于React:将道具传递给功能组件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！