javascript - react - 类型错误 : Cannot read property 'trim' of undefined

Question

我不确定我在这里做错了什么。

class Login extends Component {

    render() {
        const username = "me@domain.com  ";
        console.log(username)
        const password = this.refs.password;
        const creds = {
            username: username.value.trim(),
            password: password.value.trim()
        };
        const errorMessage  = this.props;

        return ( ... ) } }

控制台显示“me@domain.com”，但在用户名:username.value.trim()上出错

  11 | console.log(username)
  12 | const password = this.refs.password;
  13 | const creds = {
> 14 |     username: username.value.trim(),
  15 |     password: password.value.trim()
  16 | };
  17 | const errorMessage  = this.props;

Answer 1

username.value.trim()

username 本身是一个字符串，您不需要从中获取值。只是 trim 一下。

const creds = {
        username: username.trim(),
        password: password.value.trim()
    };