how to get data from WebMethod in angular2

Your method is just returning Observable, they will just sit as a function. Observable are lazy in nature. They wouldn't get executed until you subscribe to them.

AttendanceMast() {   return this._http.get("AttendanceMast.apsx/GetDistinctBatch")         .map((response) => response.toString()); //better do it response.json();}myService.AttendanceMast().subscribe(  data => console.log(data);)

dataservice

getwithParamter(): Observable<JSON> {                            this.headers = new Headers();            this.headers.append('Content-Type', 'application/json; charset=utf-8');                           let options = new RequestOptions({                method: RequestMethod.Post,                url: "AttendanceMast.aspx/HelloWorldss",                                   headers: this.headers,                body:{program: 'pravin'}  //same like data: "{}" in ajax            });           return this._http.request(new Request(options)).retry(2)             .map((response: Response) => response.text())            .do(data => console.log('All: ' + JSON.stringify(data)))            .catch(this.handleError);                      }  handleError(error: any) {    console.error('An error occurred', error);    return Promise.reject(error.message || error);}

C#

[System.Web.Services.WebMethod]public static string HelloWorldss(string program){    return "welcome Angular" + program;}

call

  this.dataService.getwithParamter().subscribe(        tradeshows => this.getwithparamter = tradeshows,        error =>  console.error('Error: ' +error)    );

print this variable showing your output this.getwithparamter

I assume you are using the standard configuration for a WebService. If so, I believe your problem is that your are using the inbuilt rest capability of Angular2 to access a WebService, aka a Soap service, returning xml soap envelopes. Hence the 404.

Unfortunately, you have a bit more work to do to make it work than if you were accessing a rest service.Have a look at angular2-soap on github. It should get you on the right track.