React，js语法不好400请求bug

Question

我试图发送一个Post请求到我的API，但收到了错误的语法错误。我参考了StackOverflow上的这篇文章，但我看不出我的代码有什么不同。

反应.js，如何将多部分/表单数据发送到服务器

export default class CapsuleForm extends React.Component {
  constructor (props) {
    super(props);

    this.state = {
      userUrl: this.props.auth.domain + "/users/" + this.props.userID,
      dateToPost: moment(),
      image: "",
      caption: "",
      redirect: false
    };

    this.handleChange = this.handleChange.bind(this);
    this.handleFormSubmit = this.handleFormSubmit.bind(this);
    this.handleDateChange = this.handleDateChange.bind(this);
  }

  handleFormSubmit(e) {
    e.preventDefault();
    var form = new FormData()
    form.append("user", this.state.userUrl);
    form.append("dateToPost", this.state.dateToPost.format());
    form.append("image", this.state.image.files[0]);
    form.append("caption", this.state.caption);

    for (var pair of form.entries()) {
       console.log(pair[0]+ ', ' + pair[1]);
    }

    this.props.auth.postCapsule(
      form
    ).then(() => {
       this.setState({redirect: true})
    })
    .catch(err =>{
        alert(err);
    })
  }

  handleDateChange(date) {
    this.setState({
      dateToPost: date
    });
  }

  handleChange(e) {
    this.setState(
         {
             caption: e.target.value
         }
     )
  }

  render() {
    function FieldGroup({ id, label, help, ...props }) {
      return (
        <FormGroup controlId={id}>
          <ControlLabel>{label}</ControlLabel>
          <FormControl {...props} />
        </FormGroup>
      );
    }

    return (
      <Form onSubmit={this.handleFormSubmit.bind(this)}>
        <h1> Create a SnapCapusle </h1>
        {/* TODO Find out why FieldGroup component does not pass onChange function
         correctly */}
        <ControlLabel> Date </ControlLabel>
        <DatePicker
          selected={this.state.dateToPost}
          onChange={this.handleDateChange}
          style={ css }
          showTimeSelect
          dateFormat="LLL"
        />
        <FormGroup id="1">
          <ControlLabel> File </ControlLabel>
          <FormControl
            type="file"
            label="Image"
            name="image"
            inputRef={ref => {
              this.state.image = ref;
            }}
          />
        </FormGroup>
        <FormGroup id="2">
          <ControlLabel> Caption </ControlLabel>
          <FormControl
            type="text"
            placeholder="Enter text"
            name="caption"
            onChange={this.handleChange}
          />
        </FormGroup>
        <FormGroup>
            <Button type="submit"> Submit </Button>
        </FormGroup>
      </Form>
    );
  }
}

这是后胶囊功能。

postCapsule(formData) {
      console.log("PostCapsule called to " + `${this.domain}/snapcapsule/`)
      return fetch(`${this.domain}/snapcapsule/`, {
          method: 'POST',
          credentials: 'same-origin',
          body: formData
      })
    }

Answer 1

我通过在控制台中查看http错误来解决此问题。如果您转到“网络”选项卡，则可以单击该请求，它将为您提供一条错误消息。错误消息告诉我没有与我给出的网址匹配的网址。我意识到我忘了用“/”结束用户URL。

this.state = {
    userUrl: this.props.auth.domain + "/users/" + this.props.userID + "/",
    dateToPost: moment(),
    image: "",
    caption: "",
    redirect: false
};