Angular 2 Token: Response for preflight has invalid HTTP status code 400

Question

I have an Angular2/TypeScript application running i Visual Studio Code.

An API running in VS 2015. This is the API project: http://www.asp.net/web-api/overview/security/

Answer 1

I found that in angular 4 you have to make it like this.

public addQuestion(data: any): Observable  {

    let headersObj = new Headers();
    headersObj.set('Content-Type', 'application/x-www-form-urlencoded');

    let requestArg: RequestOptionsArgs = { headers: headersObj, method: "POST" };

    var params = new URLSearchParams();
    for(let key of Object.keys(data)){ 
      params.set(key,data[key]);
    };

    return this.http.post(BaseApi.endpoint + 'Question', params.toString(), requestArg)
    .map((res: Response) => res.json().data);

  }