Hangfire and VB.NET - Gettings things configured i

问题:

Earlier this week I ran across Scott Hanselman's post about background processing in ASP.NET (http://www.hanselman.com/blog/HowToRunBackgroundTasksInASPNET.aspx). I've written routines in the past that automatically hits a page every so often to run some tasks, but this background processing idea is something I never even considered, and Hangfire (http://hangfire.io/) looks perfect for my background processing needs (mainly sending emails).

To get HangFire going (after installing it via NuGet) I need to get it started up in the Application Startup class. The documentation provides C# code that I'm not sure how to convert to VB.NET. It looks like some lambda code, which I'm somewhat familiar with through my use of LINQ, but I can't quick figure this one out.

public void Configure(IAppBuilder app)
{
    app.UseHangfire(config =>
    {
        config.UseSqlServerStorage("<connection string or its name>");
        config.UseServer();
    });
}

This is where I'm starting, which is basically next to nothing, I know... :)

Public Sub Configuration(app As IAppBuilder)
     'This is where I know this code should go... 
End Sub

I'd appreciate some direction or explanation as to what's going on here and how to port this code to VB.NET. Thanks!

回答1:

You should be able to write that as:

Public Sub Configure(app As IAppBuilder)
    Dim act = Sub(config As IBootstrapperConfiguration)
                config.UseSqlServerStorage("<...>")
                config.UseServer()
              End Sub

    app.UseHangfire(act)
End Sub

For more on creating multi line lambdas in VB.Net, refer to the MSDN.

回答2:

I must be doing something wrong. I too found Scott's blog post quite intriguing. I too use VB and was having trouble. The code @rfernandes shared was a welcome site. However, I get an error at run time.

Here's my code:

Public Sub Configuration(app As IAppBuilder)
    Dim act = Sub(config As IBootstrapperConfiguration)
                  config.UseSqlServerStorage("HangfireDb")
                  config.UseServer()
              End Sub

    app.UseHangfire(act)
End Sub

The error occurs in the config.UseSqlServerStorage("HangfireDb") call. An SqlException with the message "Column, parameter, or variable #5: Cannot find data type datetime2" is thrown. I'm not sure what to do about this one.

*** After posting this non-answer I realized that I needed to post a separate question. See this Stackoverflow question for the rest of the story.