Getting random response on hitting the POST API

Question

I am getting different response on hitting the same API. Sometimes its 200, and sometimes its showing cancelled. When I am hitting the API from Postman, its working absolutely fine but when I am hitting API from the js file, its showing this error in the network tab. Tried using Fetch but still facing the same issue.

Here is my API code

using PostQuestion.Models;
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using System.Web.Http.Description;

namespace PostQuestion.Controllers
{
    public class LoginController : ApiController
    {
        public string conString = "Data Source=DESKTOP-DO57SLF\\SQLEXPRESS;Initial Catalog=doubtdb;Integrated Security=True";
        [HttpPost]
        [Route("login")]
        [ResponseType(typeof(LoginResponse))]
        public IHttpActionResult Login([FromBody] LoginRequest login)
        {
            LoginResponse res = new LoginResponse();
            if (string.IsNullOrEmpty(login.Username))

            {
                res.Success = false;
                res.Message = "Username can not be empty";
                return Ok(res);

            }
            
            if (string.IsNullOrEmpty(login.Password))
            {
                res.Success = false;
                res.Message = "Password can not be empty";
                return Ok(res);
            }

            try
            {

                SqlConnection con = new SqlConnection(conString);
                con.Open();

                if (con.State == System.Data.ConnectionState.Open)
                {
                    String Username = login.Username.Trim();
                    String Password = login.Password.Trim();
                    if (Username.Contains(" "))

                    {
                        res.Success = false;
                        res.Message = "Invalid Credentials!";
                        return Ok(res);

                    }
                    if (Username.Contains('=') && Username.Contains("or"))
                    {
                        res.Success = false;
                        res.Message = "Invalid Credentials!";
                        return Ok(res);
                    }
                    SqlCommand cmd = new SqlCommand("spchecklogin", con);
                    cmd.CommandType = System.Data.CommandType.StoredProcedure;
                    cmd.Parameters.Add("@Username", SqlDbType.VarChar).Value = Username;
                    cmd.Parameters.Add("@Password", SqlDbType.VarChar).Value = Password;
                    cmd.Parameters.Add("@Count", SqlDbType.Int).Direction = ParameterDirection.Output;
                    cmd.ExecuteNonQuery();
                    int getcount = Convert.ToInt32(cmd.Parameters["@Count"].Value);
                    con.Close();
                    if (getcount == 1)
                    {
                        res.Success = true;
                        res.Message = "Login Successful!";
                        return Ok(res);
                    }
                    else
                    {
                        res.Success = false;
                        res.Message = "Invalid Credentials!";
                        return Ok(res);
                    } 
                    
                }
                else
                {
                    res.Success = false;
                    res.Message = "Unable to Login";
                    return Ok(res);
                }


            }
            catch (Exception ex)
            {
                res.Success = false;
                res.Message = "Unable to Login" + ex;
                return Ok(res);
            }

        }
    }
}

Here is my js code:

function Login() {

var username=document.getElementById("Email").value;
var password=document.getElementById("Password").value; 

var xhttp = new XMLHttpRequest();
var raw = JSON.stringify({"Username":username,"Password":password});
xhttp.onreadystatechange = function() {
     if (this.readyState == 4 && this.status == 200) {
         alert(this.responseText);
     }
};
xhttp.open("POST", "https://localhost:44393/login", true);
xhttp.setRequestHeader("Content-type", "application/json");
xhttp.send(raw);

}

When you navigate to a new page, AJAX requests are cancelled. It is likely you are navigating between pages. Click `All` next to `XHR`. — mjwills, Dec 26 '20 at 13:16
In the ALL tab, everything shows 200 status except the login API And both Gordan and GORDAN will be allowed since they don't contain '=' sign — Siddharth Kumar Shukla, Dec 26 '20 at 13:23
`In the ALL tab, everything shows 200 status except the login API` Yes. The point I am making is that you are likely moving to a new page. This causes the AJAX requests to be cancelled. I don't have a different way to word that, unfortunately. — mjwills, Dec 26 '20 at 13:29
But why is `gordon=` not allowed as a username? What is special about `=` and `or`? — mjwills, Dec 26 '20 at 13:30
Have you read https://stackoverflow.com/questions/16585157/ajax-post-getting-cancelled/16585362 and https://stackoverflow.com/questions/7577275/jquery-ajax-requests-are-getting-cancelled-without-being-sent ? — mjwills, Dec 26 '20 at 13:40
It worked after chaning the type to button Thanks a lot @mjwills — Siddharth Kumar Shukla, Dec 26 '20 at 13:52

score 0 · Answer 1 · answered Dec 26 '20 at 13:54

0

I was finally able to resolve the issue Earlier my button type was submit due to which the page was getting redirected After changing the type to button, everything is working fine Thanks everyone for your precious time.

answered Dec 26 '20 at 13:54

Siddharth Kumar Shukla

117
1
5

Getting random response on hitting the POST API

1 Answers1