typescript async-await导致变量未定义

Question

我遇到这个问题有一段时间了，在异步update_vm_raw_device函数中vm_res是未定义的，函数update_vm_raw_device运行，但是值是像/mnt/tank/ds/test_file_test_VM_undefined一样更新的，请注意最后没有定义。

async customSubmit(value) {
  const path = value.raw_file_directory+ '/' + value.raw_filename+ '_'+ value.name;
    const payload = {}
    const vm_payload = {}
    ......SNIP..........
    this.ws.call('vm.get_sharefs').subscribe((get_sharefs)=>{
      if(!get_sharefs){
        this.ws.call('vm.activate_sharefs').subscribe((sharefs)=>{
          this.ws.call('vm.create', [vm_payload]).toPromise().then(vm_res => {
            // here the assignment happens, but  this.vm_res is undefined in 
            // async update_vm_raw_device function.
            this.vm_res = vm_res;
          });
        }
      )
      }
      else {
        this.ws.call('vm.create', [vm_payload]).toPromise().then(vm_res => {
          this.vm_res = vm_res;
        });
      }
    },)
    await this.update_vm_raw_device(vm_payload, this.vm_res);
  }

  async update_vm_raw_device(vm_payload: any, vm_res: number) {
  vm_payload.path = vm_payload.path+"_"+this.vm_res
   await this.ws.call('datastore.update'[vm_payload])]).toPromise().then(
       res=>{});}

Answer 1

async/await与此无关。

据我所知，this.vm_res只会在subscribe回调中被设置，这在你调用this.update_vm_raw_device()之前是不会发生的。

您是否打算将对this.update_vm_raw_device()的调用放在订阅处理程序中？也许在设置该值之后？