Angular2 http.post:使用subscribe创建promise

Question

我正在尝试创建一个函数,它返回一个Promise作为代码:(someprovider.ts)

postToPaymentApi(url:string, data:string, options:RequestOptions, order:Order):Promise<any>{
let result =  this.http.post(url, data, options).map(res => res.json())
  .subscribe(data => {
    // all my logic here!
    });
  }, error => {
    console.log(error)
  })

  return new Promise((resolve)=>{
    resolve(result)
  })

}

问题是,当我调用这个函数时,我没有得到数据,因为这个帖子需要几秒钟才能完成,我在完成后得到了承诺.

this.postToPaymentApi(url, data, options, order).then(data => {
    console.log(data);
  })

我究竟做错了什么？

Answer 1

如果你想创建一个返回promise的函数,你的函数应该是:

postToPaymentApi(url:string, data:string, options:RequestOptions, order:Order):Promise<any >{
   return new Promise((resolve, reject) => {
          this.http.post(url, data, options)
           .map(res => res.json())
           .subscribe(data => {
             resolve(data);
            }
           }, error => {
             console.log(error)
             reject({error: error});
           });
        });
}