Javascript react组件中未定义的参数

我有一个模拟登录的navbar组件，它从一个模式向我发送用户电子邮件，但当我向signinmenu组件发送属性时，电子邮件显示为未定义

我还发送了一个注销功能，这是工作，但字符串电子邮件显示为未定义

导航栏组件

render() {
    const { auth } = this.props;
    const authenticated = auth.authenticated;

    return (
      <Menu inverted fixed="top">
        <Container>
          <Menu.Item as={Link} to="/" header>
            <img src="/assets/images/logo.png" alt="logo" />
            Re-vents
          </Menu.Item>
          <Menu.Item as={NavLink} to="/events" name="Events" />
          <Menu.Item as={NavLink} to="/test" name="Test" />
          {authenticated &&
          <Menu.Item as={NavLink} to="/people" name="People" />}

          {authenticated &&
          <Menu.Item>
            <Button
              as={Link}
              to="/createEvent"
              floated="right"
              positive
              inverted
              content="Create Event"
            />
          </Menu.Item>}
          {authenticated ? (
            <SignedInMenu currentUser={auth.currentUser} signOut={this.handleSignOut} /> 
          ) : (
            <SignedOutMenu signIn={this.handleSignIn} register={this.handleRegister} />
          )}
        </Container>
      </Menu>
    );
  }
}

import React from 'react';
import { Menu, Image, Dropdown } from 'semantic-ui-react';
import { Link } from 'react-router-dom'

const SignedInMenu = ({signOut, currentuser}) => {
  console.log(currentuser)
  return (
    <Menu.Item position="right">
      <Image avatar spaced="right" src="/assets/images/user.png" />
      <Dropdown pointing="top left" text={currentuser}>
        <Dropdown.Menu>
          <Dropdown.Item text="Create Event" icon="plus" />
          <Dropdown.Item text="My Events" icon="calendar" />
          <Dropdown.Item text="My Network" icon="users" />
          <Dropdown.Item text="My Profile" icon="user" />
          <Dropdown.Item as={Link} to='/settings' text="Settings" icon="settings" />
          <Dropdown.Item onClick={signOut} text="Sign Out" icon="power" />
        </Dropdown.Menu>
      </Dropdown>
    </Menu.Item>
  );
};

export default SignedInMenu;


I know the string is on the props but when I tried to show in the text attribute or console.log appears as undefined

render（）{
const{auth}=this.props；
const authenticated=auth.authenticated；
返回(
出口
{已验证&&
}
{已验证&&
}
{认证(
) : (
)}
);
}
}

符号菜单组件

render() {
    const { auth } = this.props;
    const authenticated = auth.authenticated;

    return (
      <Menu inverted fixed="top">
        <Container>
          <Menu.Item as={Link} to="/" header>
            <img src="/assets/images/logo.png" alt="logo" />
            Re-vents
          </Menu.Item>
          <Menu.Item as={NavLink} to="/events" name="Events" />
          <Menu.Item as={NavLink} to="/test" name="Test" />
          {authenticated &&
          <Menu.Item as={NavLink} to="/people" name="People" />}

          {authenticated &&
          <Menu.Item>
            <Button
              as={Link}
              to="/createEvent"
              floated="right"
              positive
              inverted
              content="Create Event"
            />
          </Menu.Item>}
          {authenticated ? (
            <SignedInMenu currentUser={auth.currentUser} signOut={this.handleSignOut} /> 
          ) : (
            <SignedOutMenu signIn={this.handleSignIn} register={this.handleRegister} />
          )}
        </Container>
      </Menu>
    );
  }
}

import React from 'react';
import { Menu, Image, Dropdown } from 'semantic-ui-react';
import { Link } from 'react-router-dom'

const SignedInMenu = ({signOut, currentuser}) => {
  console.log(currentuser)
  return (
    <Menu.Item position="right">
      <Image avatar spaced="right" src="/assets/images/user.png" />
      <Dropdown pointing="top left" text={currentuser}>
        <Dropdown.Menu>
          <Dropdown.Item text="Create Event" icon="plus" />
          <Dropdown.Item text="My Events" icon="calendar" />
          <Dropdown.Item text="My Network" icon="users" />
          <Dropdown.Item text="My Profile" icon="user" />
          <Dropdown.Item as={Link} to='/settings' text="Settings" icon="settings" />
          <Dropdown.Item onClick={signOut} text="Sign Out" icon="power" />
        </Dropdown.Menu>
      </Dropdown>
    </Menu.Item>
  );
};

export default SignedInMenu;


I know the string is on the props but when I tried to show in the text attribute or console.log appears as undefined

从“React”导入React；
从“语义ui反应”导入{菜单、图像、下拉列表}；
从“react router dom”导入{Link}
const signedMenu=（{signOut，currentuser}）=>{
console.log（当前用户）
返回(
);
};
导出默认签名菜单；
我知道字符串在道具上，但当我尝试在文本属性或console.log中显示时，显示为未定义

SignedMenu是一个功能组件，它的所有道具都包含在第一个参数中。所以你需要像这样使用它：

SignedInMenu = (props) => {
  return <h1>Hello, {props.name}</h1>;
}

signedMenu=（道具）=>{
返回Hello，{props.name}；
}

这是一个案例输入错误-您在父组件中以

currentUser

的身份传递道具，在子组件中以

currentUser

的身份接收道具。你需要

<SignedInMenu currentuser={auth.currentUser} signOut={this.handleSignOut} /> 

---

避免这些问题是很棘手的，但是在某些情况下，使用可以帮助，你可以考虑把它们添加到你的项目中。p> Sergio在他的组件声明中使用es6对象解构。您是wright，但最好将函数中的参数更改为currentUser，因为在其他地方使用camel case，这可能是我要做的。没问题。祝你的项目好运！