MVC: Run a method on Application startup without calling it from Application_Start

Question

I have a class with a method that should run on application startup. I don't want to call this method directly from Application_Start event. What's the best way to get this class instantiated and method run on application_start?

In other words, I want to inject this code into application startup.

Answer 1

I've noticed that some people use WebActivatorEx.PostApplicationStartMethod. I've not delved into the details but it is the first place I would look. Here's an example of a class registered to automatically run when RegisterBundles is called. One of the other hooks may be what you are looking for.

[assembly: WebActivatorEx.PostApplicationStartMethod(typeof(BootstrapBundleConfig), "RegisterBundles")]

namespace Deloitte.EmploymentMemo.Presentation.App_Start
{
    public class BootstrapBundleConfig
    {
        public static void RegisterBundles()
        {
            // Add @Styles.Render("~/Content/bootstrap") in the <head/> of your _Layout.cshtml view
            // For Bootstrap theme add @Styles.Render("~/Content/bootstrap-theme") in the <head/> of your _Layout.cshtml view
            // Add @Scripts.Render("~/bundles/bootstrap") after jQuery in your _Layout.cshtml view
            // When <compilation debug="true" />, MVC4 will render the full readable version. When set to <compilation debug="false" />, the minified version will be rendered automatically
            BundleTable.Bundles.Add(new ScriptBundle("~/bundles/bootstrap").Include("~/Scripts/bootstrap.js"));
            BundleTable.Bundles.Add(new StyleBundle("~/Content/bootstrap").Include("~/Content/bootstrap.css"));
            BundleTable.Bundles.Add(new StyleBundle("~/Content/bootstrap-theme").Include("~/Content/bootstrap-theme.css"));
        }
    }
}

Answer 2

One of possible solutions to use OWIN startup.

Install nuget package: install-package Microsoft.Owin.Host.SystemWeb

Add to appsettings startup class:

   <appSettings>
          <add key="owin:appStartup" value="MyProject.Code.Startup" />
   </appSettings>

And by convention you will need class with method called Configuration:

    public class Startup
    {
            public void Configuration(IAppBuilder app)
            {
                app.Run(context =>
                {
                    string t = DateTime.Now.Millisecond.ToString();
                    return context.Response.WriteAsync(t + " Production OWIN App");
                });
            }
    }

Or do anything you need.

If you interesting in it, check it asp.net: OWIN and Katana project

Answer 3

Use delegates. They hold references to methods and that give you possibility to call some methods at one time; An example of using delegates :

public delegate void myDelegate();

private static void Main()
{
    myDelegate myFunctions = Method1; //initialize delegate with Method1
    myFunctions += Method2;           //Add Method2 to delegate

    myFunctions(); //call all methods added to delegate
}

public static void Method1()
{
    Console.WriteLine("Hello from method1");
}

public static void Method2( )
{
    Console.WriteLine("Hello from method2");
}

This will call both Method1 and Method2