不会从'react-bootstrap'导出'ControlLabel'

Question

您好，我正在React中创建一个登录表单，以使用软件包的Checkbel来检查登录参数，但是当我运行代码时，我抛出了此异常： ./src/App.js尝试导入错误：“ ControlLabel”为不是从'react-bootstrap'导出的。我该如何解决？

反应代码：

import React, { Component } from "react";
import { Form,Button, FormGroup, FormControl, ControlLabel } from "react-bootstrap";
import "./Login.css";
import Bootstrap from "react-bootstrap";

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

    this.state = {
      email: "",
      password: ""
    };
  }

  validateForm() {
    return this.state.email.length > 0 && this.state.password.length > 0;
  }

  handleChange = event => {
    this.setState({
      [event.target.id]: event.target.value
    });
  }

  handleSubmit = event => {
    event.preventDefault();
  }

  render() {
    return (
      <div className="Login">
        <form onSubmit={this.handleSubmit}>
          <FormGroup controlId="email" bsSize="large">
            <ControlLabel>Email</ControlLabel>
            <FormControl
              autoFocus
              type="email"
              value={this.state.email}
              onChange={this.handleChange}
            />
          </FormGroup>
          <FormGroup controlId="password" bsSize="large">
            <ControlLabel>Password</ControlLabel>
            <FormControl
              value={this.state.password}
              onChange={this.handleChange}
              type="password"
            />
          </FormGroup>
          <Button
            block
            bsSize="large"
            disabled={!this.validateForm()}
            type="submit"
          >
            Login
          </Button>
        </form>
      </div>
    );
  }
}

Answer 1

尝试使用FormLabel代替ControlLabel。

Answer 2

<ControlLabel>来自旧版本的 react-bootstrap。当前版本（“react-bootstrap”：“^1.4.3”）使用<FormLabel>或<Form.Label>

Answer 3

根据这个 url https://react-bootstrap.github.io/components/buttons/#button-props和你的版本，你应该像这样修改你的代码。

    import React, { Component } from "react";
    import Form from 'react-bootstrap/Form'
    import Button from 'react-bootstrap/Button'
    import Bootstrap from "react-bootstrap";

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

        this.state = {
          email: "",
          password: ""
        };
      }

      validateForm() {
        return this.state.email.length > 0 && this.state.password.length > 0;
      }

      handleChange = event => {
        this.setState({
          [event.target.id]: event.target.value
        });
      }

      handleSubmit = event => {
        event.preventDefault();
      }

      render() {
        return (
          <div className="Login">
            <Form onSubmit={this.handleSubmit}>
              <Form.Group controlId="email" bsSize="large">
                <Form.Control
                  autoFocus
                  type="email"
                  value={this.state.email}
                  onChange={this.handleChange}
                />
              </Form.Group>
              <Form.Group controlId="password" bsSize="large">
                <Form.Control
                  value={this.state.password}
                  onChange={this.handleChange}
                  type="password"
                />
              </Form.Group>
              <Button
                block
                bsSize="large"
                disabled={!this.validateForm()}
                type="submit"
              >
                Login
              </Button>
            </Form>
          </div>
        );
      }
    }

Answer 4

这"react-bootstrap": "^1.0.0-beta.16",不包含 ControlLabel，所以使用卸载它

   npm uninstall react-bootstrap

然后用这个"react-bootstrap": "^0.32.4"版本重新安装

   npm install react-bootstrap@0.32.4 --save

肯定会解决这个问题