如何创建获取数据的发布请求

Question

当用户点击商家名称时，需要将其保存为收藏夹，获取商家 ID 和用户 ID 并将其插入数据库。后端已准备好获取 post 请求，但我还没有弄清楚如何发送该数据。

这是我一直使用的代码，用于获取带有用户 ID 和业务 ID 的最喜欢的业务（在后端有一个查询 SELECT * from business 等...）

如何更改此代码以发出 POST 请求？ （插入一个新的最爱业务）假设在后端有一个带有 INSERT INTO ....的查询）

saveBusiness = (e) => {
    fetch("http://localhost:3030/favbusiness/" + this.state.selectedUserid + "/" + this.state.selectedBusiness)
    .then((response) => {
      return response.json();
    })
    .then(data => {
        let favBusinessFromApi = data.map(favorite => {
          return { value: favorite.businessid }
        });
        this.setState({
          favoriteBusiness: favBusinessFromApi
        });
    .catch(error => {
      console.log(error);
    });
  }  ```

Answer 1

你需要在 URL 之前添加 OPTIONS 来表示它是一个 POST，像这样：

saveBusiness = (e) => {
    const OPTIONS = {
        method: 'POST'
    }
    fetch("http://localhost:3030/favbusiness/" + this.state.selectedUserid + "/" + this.state.selectedBusiness, OPTIONS)
    .then((response) => {
      return response.json();
    })
    .then(data => {
        let favBusinessFromApi = data.map(favorite => {
          return { value: favorite.businessid }
        });
        this.setState({
          favoriteBusiness: favBusinessFromApi
        });
    .catch(error => {
      console.log(error);
    });
  }

如果您需要更多选项或更多信息：https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API/Using_Fetch

Answer 2

您可以简单地添加method: 'POST',

saveBusiness = (e) => {
    fetch("http://localhost:3030/favbusiness/" + this.state.selectedUserid + "/" + this.state.selectedBusiness,{
  method: 'POST', 
})
    .then((response) => {
      return response.json();
    })
    .then(data => {
        let favBusinessFromApi = data.map(favorite => {
          return { value: favorite.businessid }
        });
        this.setState({
          favoriteBusiness: favBusinessFromApi
        });
    .catch(error => {
      console.log(error);
    });
  };

阅读有关 fetch 以及如何传递标头 Here 的更多信息

Answer 3

saveBusiness = (e) => {
    fetch("http://localhost:3030/favbusiness/" + this.state.selectedUserid + "/" + this.state.selectedBusiness, {
    method: 'POST',
    body: JSON.stringify(e.data), // this should be the data that you want to post
})
    .then((response) => {
      return response.json();
    })
    .then(data => {
        let favBusinessFromApi = data.map(favorite => {
          return { value: favorite.businessid }
        });
        this.setState({
          favoriteBusiness: favBusinessFromApi
        });
    .catch(error => {
      console.log(error);
    });
  }