Unexpected token < in JSON at position 1 ----ionic3

Question

The data can be inserted into the database and the JSON also can be generated very well but why is 'Unexpected token < in JSON at position 1' thrown?

The problem has been shown in the picture

signup.ts

signup(){
     this.authService.postData(this.userData,'signup').then((result) => {
      this.responseData = result;
      if(this.responseData.userData){
      console.log(this.responseData);
      localStorage.setItem('userData', JSON.stringify(this.responseData));
      this.navCtrl.push(LoginPage);
      }
      else{ {swal({
        title: "User already exist.Please try again",
         })
         } }
    }, (err) => { ;
      // Error log
    });

}

Answer 1

You're getting BR tag in your response, and because of that it can't be parsed to JSON, so remove the

>  <br />batman2@gmail.comhere

tag from your response.

Answer 2

您可以使用rxjs 映射操作符来验证服务中的JSON响应：

this.http.get(YOUR_URL).map(res => res.json());