MVC : Generate random OTP (one time password)

In this article I am going to explain how to generate random OTP (one time password) in asp.net MVC application.

Description:

I want to generate OTP. OTP can be numeric or alphanumeric and it is used widely to validate the user’s information such as mobile number, in banks for transaction etc.

Implementation:

Add controller

Add an empty controller to project. Create 3 action to generate OTP, one to generate numeric and 2^nd one alphanumeric.

Complete code of controller:

using System;

using System.Collections.Generic;

using System.Data;

using System.Data.Entity;

using System.Linq;

using System.Web;

using System.Web.Mvc;

using infinitescroll.Models;

using System.Web.Security;

namespace infinitescroll.Controllers

{

    public class OTP : Controller

    {

       

        public ActionResult Index()

        {

            return View();

        }

        public ActionResult GenerateOTP()

        {

            return View();

        }

        [HttpPost]

        public ActionResult GenerateNumericOTP()

        {

            string numbers = "0123456789";

            Random objrandom = new Random();

            string strrandom = string.Empty;

            for (int i = 0; i < 5; i++)

            {

                int temp = objrandom.Next(0, numbers.Length);

                strrandom += temp;

            }

            ViewBag.otp = strrandom;

            return View("GenerateOTP");

        }

        [HttpPost]

        public ActionResult GenerateAlphaNumericOTP()

        {

            string numbers = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

            Random objrandom = new Random();

            string passwordString = "";

            string strrandom = string.Empty;

            for (int i = 0; i < 8; i++)

            {

                int temp = objrandom.Next(0, numbers.Length);

                passwordString = numbers.ToCharArray()[temp].ToString();

                strrandom += passwordString;

            }

            ViewBag.anotp = strrandom;

            return View("GenerateOTP");

        }

    }

}

Add view

Add view for GenerateOTP action.

Complete source of View:

@{

    ViewBag.Title = "Generate OTP";

}

@using (Html.BeginForm("GenerateNumericOTP", "OTP"))

{

    <table>

        <tr>

            <td>Click on button to Generate Numeric OTP :</td>

            <td><input id="Submit1" type="submit" value="Generate OTP" /></td>

        </tr>

        <tr>

            <td></td>

            <td>@ViewBag.otp</td>

        </tr>

    </table>

}

@using (Html.BeginForm("GenerateAlphaNumericOTP", "OTP"))

{

    <table>

        <tr>

            <td>Click on button to Generate Alphanumeric OTP :</td>

            <td><input id="Submit1" type="submit" value="Generate OTP" /></td>

        </tr>

        <tr>

            <td></td>

            <td>@ViewBag.anotp</td>

        </tr>

    </table>

}