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RE: MVC3 and custom Captcha

Posted By:      Posted Date: April 14, 2011    Points: 0   Category :ASP.Net

I'm writing my own CAPTCHA generator for MVC3 - mostly to learn the MVC3 architecture in more depth. I'm looking for a coding solution rather than an existing solution. I'm looking for ways in which I can integrate my solution in to MVC3 WITHOUT using the ViewBag or a custom HttpHandler.

I'm fairly new to MVC and I'm finding the concepts behind it quite a challenge. I've written the captcha generator, and now I need to do is plumb it in to the MVC framework. Below is the signature of my captcha class:

	public class Captcha {
		public string CaptchaString {
		public Captcha(string captchaString = "") {
		public static string GenerateCaptchaString(Int32 length = 0) {
		public byte[] GetCaptchaImageBytes() {


The code I've ripped out of the methods works fine and returns everything correctly. The issue I'm having is getting it working with MVC itself.

The first thing I tried was exposing the following method on my controller:

		public FileResult CaptchaImage() {
			var captcha = new Captcha();

			return File(captcha.GetCaptchaImageBytes(), "image/png");


Then calling @Url.Action("CaptchaImage") in the view. Voila, it generates a captcha on every refresh, but this in itself is pretty useless. I need to be able to

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