封装JSONP

import originJSONP from 'jsonp';
 
export default function jsonp(url, data, option){
  url += (url.indexOf('?')<0?'?':'&')+param(data)
  return new Promise((resolve,reject)=>{
      originJSONP(url,option,(err,data)=>{
        if(!err){
          resolve(data)
        }else{
          reject(err)
        }
      })
  })
}


function param(data){
  let url='';
  for (var k in data){
    let value=data[k] !== undefined?data[k]:'';
    url += `&${k}=${encodeURIComponent(value)}`
  }
  return url ? url.substring(1):''
}