Question

我在我的angular2 +组件中做了一个函数，输出首先出现，该函数随后运行，因此，我想要的适当输出随后出现。该函数将变量参数和http请求一起传递给后端NodeJS。并返回结果。我想找到我能找到的长度。但是，我想通过传递多个参数多次调用此参数。所以我将其定义为异步函数。代码是-

app.component.ts

 // Function 1

 getNodesCount() {

        console.log("INSIDE  getNodesCount()")

          if (this.selectedAPIName.length == 1) {

            this.nodesObjQ1 = {
                'relationObj': this.menuItem,
                'nodeValue1': this.selectedAPIName[0]
            }

            this.callFunctionCount(this.nodesObjQ1).then((rs: any[]) 
            => {

            this.nodesObjL1 = rs;
            });


            console.log("this.nodesObjL1 =", this.nodesObjL1)
        }

  }


  //Function 2


  async callFunctionCount(trueNodesObject) {

    console.log("nodesObj =", trueNodesObject);

    await new Promise(next => { 

    this.http.get("http://localhost:3003/seekExtraction/nodesObj/" + 
         JSON.stringify(trueNodesObject))
        .map(Response => Response)

        .catch((err) => {
            console.log("err =", err)
            return Observable.throw(err);

        })
            .subscribe((res: Response) => {

            console.log("XXXXXXXXXXXX Response on /seekExtraction", 
            res);

               this.nodesInfo = res;

            this.nodesLength = this.nodesInfo.records.length
            next()
        })

        });

        console.log("return this.nodesLength =",  this.nodesLength)
         return this.nodesLength;


       }

主要产出-

 this.nodesObjL1 = undefined

 return this.nodesLength = 2

请帮助检索该值-

 this.nodesObjL1

此值之后

 this.nodesInfo.records.length=  2

Answer 1

实际的最小示例将有助于确保干净的代码...但是尝试一下...

        getData = function (trueNodesObject) {

            return new promise((resolve, reject) => {
                this.http.get("http://localhost:3003/seekExtraction/nodesObj/" +
                    JSON.stringify(trueNodesObject))
                    .map(Response => Response)

                    .catch((err) => {
                        console.log("err =", err)
                        return Observable.throw(err);
                        reject(err);
                    })
                    .subscribe((res: Response) => {

                        console.log("XXXXXXXXXXXX Response on /seekExtraction",
                            res);

                        this.nodesInfo = res;

                        this.nodesLength = this.nodesInfo.records.length
                        resolve(this.nodesLength);
                        next()
                    });

            })

        }


        async function callFunctionCount(trueNodesObject) {

            console.log("nodesObj =", trueNodesObject);
            const someVal = await getData(trueNodesObject);

            console.log("return this.nodesLength =", someVal)
        }

异步的实现也不起作用angular2 +

1 个答案: