React-Native Fetch使用Promise封装(一)

项目中封装Fetch的方法

/** 
 *2017/04/23 dongtao
 * 基于 fetch 封装的 GET请求 
 * @param url 
 * @param params {} 
 * @param headers 
 * @returns {Promise} 
 */  
var HTTPUtil = {};  

HTTPUtil.get = function(url, params, headers) {  
    if (params) {  
        let paramsArray = [];  
        //encodeURIComponent  
        Object.keys(params).forEach(key => paramsArray.push(key + '=' + params[key]))  
        if (url.search(/\?/) === -1) {  
            url += '?' + paramsArray.join('&')  
        } else {  
            url += '&' + paramsArray.join('&')  
        }  
    }  
    return new Promise(function (resolve, reject) {  
      fetch(url, {  
            method: 'GET',  
            headers: headers,  
          })  
          .then((response) => {  
              if (response.ok) {  
                  return response.json();  
              } else {  
                  reject({status:response.status})  
              }  
          })  
          .then((response) => {  
              resolve(response);  
          })  
          .catch((err)=> {  
            reject({status:-1});  
          })  
    })  
}  
  
  
/** 
 * 基于 fetch 封装的 POST请求  FormData 表单数据 
 * @param url 
 * @param formData   
 * @param headers 
 * @returns {Promise} 
 */  
HTTPUtil.post = function(url, formData, headers) {  
    return new Promise(function (resolve, reject) {  
      fetch(url, {  
            method: 'POST',  
            headers: headers,  
            body:formData,  
          })  
          .then((response) => {  
              if (response.ok) {  
                  return response.json();  
              } else {  
                  reject({status:response.status})  
              }  
          })  
          .then((response) => {  
              resolve(response);  
          })  
          .catch((err)=> {  
            reject({status:-1});  
          })  
    })  
}  
  
export default HTTPUtil;  

使用

let formData = new FormData();  
formData.append("id",1060);  
        
HTTPUtil.post(url,formData,headers).then((json) => {  
    //处理 请求success  
    if(json.code === 0 ){  
            //我们假设业务定义code为0时，数据正常  
        }else{  
             //处理自定义异常  
            this.doException(json);  
        }  
   },(json)=>{  
     //TODO 处理请求fail  
        
})