About using fetch to upload images in React Native (detailed tutorial)-JS Tutorial-php.cn

About using fetch to upload images in React Native (detailed tutorial)

亚连

Release： 2018-06-01 09:11:45

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This article mainly introduces the sample code of React Native using fetch to upload images. Now I share it with you and give it as a reference.

This article introduces the sample code for React Native to use fetch to upload images, and shares it with everyone. The details are as follows:

Ordinary network request parameters are JSON objects

The request parameters for image upload use the formData object

Use fetch to upload the image code encapsulation as follows:

let common_url = &#39;http://192.168.1.1:8080/&#39;; //服务器地址
let token = &#39;&#39;;  //用户登陆后返回的token
/** 
 * 使用fetch实现图片上传
 * @param {string} url 接口地址
 * @param {JSON} params body的请求参数
 * @return 返回Promise 
 */
function uploadImage(url,params){
  return new Promise(function (resolve, reject) {
    let formData = new FormData();
    for (var key in params){
      formData.append(key, params[key]);
    }
    let file = {uri: params.path, type: &#39;application/octet-stream&#39;, name: &#39;image.jpg&#39;};
    formData.append("file", file);
    fetch(common_url + url, {
      method: &#39;POST&#39;,
      headers: {
        &#39;Content-Type&#39;: &#39;multipart/form-data;charset=utf-8&#39;,
        "x-access-token": token,
      },
      body: formData,
    }).then((response) => response.json())
      .then((responseData)=> {
        console.log(&#39;uploadImage&#39;, responseData);
        resolve(responseData);
      })
      .catch((err)=> {
        console.log(&#39;err&#39;, err);
        reject(err);
      });
  });
}

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Usage

let params = {
  userId:&#39;abc12345&#39;,  //用户id
  path:&#39;file:///storage/emulated/0/Pictures/image.jpg&#39;  //本地文件地址
}
uploadImage(&#39;app/uploadFile&#39;,params )
  .then( res=>{
    //请求成功
    if(res.header.statusCode == &#39;success&#39;){
      //这里设定服务器返回的header中statusCode为success时数据返回成功
      upLoadImgUrl = res.body.imgurl; //服务器返回的地址
    }else{
       //服务器返回异常，设定服务器返回的异常信息保存在 header.msgArray[0].desc
      console.log(res.header.msgArray[0].desc);
    }
  }).catch( err=>{ 
     //请求失败
  })

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Note: Due to different background server configurations,
let file = {uri: params.path, The type in type: 'application/octet-stream', name: 'image.jpg'} may also be multipart/form-data
The file field in formData.append("file", file) may also be images

The above is what I compiled for everyone. I hope it will be helpful to everyone in the future.

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