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What is syntax for creating a class in C# that would be equal to a Module in VB.net

I do almost all of my programming in VB.net (all flavors). I am now been assigned a task to make a new routine in an existing C# application. What I want to be able to do is pass a string variable to a class where I can figure out device type of a symbol handheld and figure out where an executable resides on device.
I am trying to keep the class to contain changes we make going forward in one place.
so a brief description is on a screen there will be a button. on that button click I want pass the text of the button to a (what would be a module in VB) a class and depending on text being passed and device type call a separate executable that lives on the device.
Everything I have tried so far has thrown errors.
On my button click i have
String Reponse = clsCallAction("Activity");
but that gets a message that clsCallAction is a type but is used like a variable.
here is the smaple of clsCallaction
internal static partial class clsCallAction
{
public static object GetPath(object lAppName)
{
string resp = "";
if (lAppName.Equals("Activity"))
{
resp = #"\application\activity.exe";
}
return resp;
}
}
If I put new in front of the clsCallAction("Activity") on button click I get a
cannot create instance of the static class 'clsCalACtion'
appreciate any pointers. very new at C#

It would look something like this:
public static class CallAction
{
public static object GetPath(object lAppName)
{
string resp = "";
if (lAppName.Equals("Activity"))
{
resp = #"\application\activity.exe";
}
return resp;
}
}
And would be used like this:
String Reponse = CallAction.GetPath("Activity");
Don't prefix classes with cls
Avoid using object if possible - it just makes everything harder work than it needs to be.. Kinda like calling everything "thing" - ("Put the thing in the thing and open the thing" is harder to understand than "put the key in the lock and open the door")

How to maintain culture through session variable

I have a multilingual web-forms web application which I am using resource files and a BasePage class which sets the culture based on the QueryString that was included in the page which is inheriting from this class. This is all working well, if a tad clunky as I am having to do this sort of thing for every button which takes the user to a different page to maintain the culture:
if (Thread.CurrentThread.CurrentCulture.ToString() == "cy-GB")
{
return "~/Secure/Details.aspx?lang=cy-GB&PersonId=" + currentPersonId;
}
else
{
return "~/Secure/Details.aspx?PersonId=" + currentPersonId;
}
I knew there was probably a better way of doing this but being a novice as it worked I simply made do.
This was until I had to implement an asp:SiteMapPath control. I initially assumed that I could simply create a resource entry for the url property like I had done for the title:
<siteMapNode
title="$resources:SiteMapLocalizations,HomePageTitle"
description="Home"
url="~$resources:SiteMapLocalizations,HomePageUrl">
However this resulted in a server error:
A potentially dangerous Request.Path value was detected from the client (:).
I've done some reading and I believe I need to somehow store the current culture to a session variable which will follow the user around so when they click 'Home' on the breadcrumb it will be consistent with the culture and grab the appropriate text from the resource files, I'm also hoping this will allow me to remove all of the IF ELSE statements I've had to write to maintain the current language throughout the application.
My question is however, where do I start with this, I cannot find any guide step by step to follow in order to achieve this, can anyone provide some instructions?

Make sure you have a button of some sort which triggers the change of language. In my case I have two versions of the header, one with an English link which will append the Query String to English and one for Welsh, something like:
ASP
<a id="languagelink" runat="server" title="Cymraeg">Cymraeg</a>
C#
if (Thread.CurrentThread.CurrentCulture.ToString() == "en-GB")
{
Uri uri = new Uri(currentPage);
languagelink.HRef = String.Format(uri.GetLeftPart(UriPartial.Path)+"?lang=cy-GB");
}
Every page which requires the language switch needs to inherit from my custom BasePage like so:
Inheritance
public partial class Secure_CustomerSummary : BasePage
Base_Page
public partial class BasePage : System.Web.UI.Page
{
protected override void InitializeCulture()
{
if (Session["language"] == null)
{
Session["language"] = "en-GB";
}
else
{
if (Request.QueryString["lang"] == null)
{
SetSessionCulture();
}
if (Request.QueryString["lang"] != null)
{
string qs = Request.QueryString["lang"];
Session["language"] = qs;
}
SetSessionCulture();
}
SetSessionCulture();
}
private void SetSessionCulture()
{
Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(Session["language"].ToString());
Thread.CurrentThread.CurrentUICulture = new CultureInfo(Session["language"].ToString());
base.InitializeCulture();
}
}

What does "DisplayClass" name mean when calling lambda?

According to this answer when code uses local variables from inside lambda methods the compiler will generate extra classes that can have name such as c__DisplayClass1. For example the following (completely useless) code:
class Program
{
static void Main()
{
try {
implMain();
} catch (Exception e) {
Console.WriteLine(e.ToString());
}
}
static void implMain()
{
for (int i = 0; i < 10; i++) {
invoke(() => {
Console.WriteLine(i);
throw new InvalidOperationException();
});
}
}
static void invoke(Action what)
{
what();
}
}
outputs the following call stack:
System.InvalidOperationException
at ConsoleApplication1.Program.<>c__DisplayClass2.<implMain>b__0()
at ConsoleApplication1.Program.invoke(Action what)
at ConsoleApplication1.Program.implMain()
at ConsoleApplication1.Program.Main()
Note that there's c__DisplayClass2 in there which is a name of a class generated by the compiler to hold the loop variable.
According to this answer c__DisplayClass "means"
c --> anonymous method closure class ("DisplayClass")
Okay, but what does "DisplayClass" mean here?
What does this generated class "display"? In other words why is it not "MagicClass" or "GeneratedClass" or any other name?

From an answer to a related question by Eric Lippert:
The reason that a closure class is called "DisplayClass" is a bit unfortunate: this is jargon used by the debugger team to describe a class that has special behaviours when displayed in the debugger. Obviously we do not want to display "x" as a field of an impossibly-named class when you are debugging your code; rather, you want it to look like any other local variable. There is special gear in the debugger to handle doing so for this kind of display class. It probably should have been called "ClosureClass" instead, to make it easier to read disassembly.

You can get some insight from the C# compiler source as available from the SSCLI20 distribution, csharp/sccomp subdirectory. Searching the code for "display" gives most hits in the fncbind.cpp source code file. You'll see it used in code symbols as well as comments.
The comments strongly suggest that this was a term used internally by the team, possibly as far back as the design meetings. This is .NET 2.0 vintage code, there was not a lot of code rewriting going on yet. Just iterators and anonymous methods, both implemented in very similar ways. The term "display class" is offset from "user class" in the comments, a clear hint that they used the term to denote auto-generated classes. No strong hint why "display" was favored, I suspect that it might have something to do with these classes being visible in the metadata of the assembly.

Based on Reflector, DisplayClass can be translated as CompilerGeneratedClass
[CompilerGenerated]
private sealed class <>c__DisplayClass16b
{
// Fields
public MainForm <>4__this;
public object sender;
// Methods
public void <cmdADSInit_Click>b__16a()
{
ADS.Initialize();
this.<>4__this._Sender = this.sender;
this.<>4__this.SelectedObject = ADS.Instance;
}
}

Error with xml serialization in c# - paramaterless constructor

I am trying to serialse a fingerprint FMD to XML using the code below, but get an error:
Error: DPUruNet.DataResult`1[DPUruNet.Fmd] cannot be serialized
because it does not have a parameterless constructor.
public void storePrint(DataResult<Fmd> resultConversion)
{
//store fingerprint as byte and insert to server------------
using (StreamWriter myWriter = new StreamWriter("test.txt", false))
{
System.Xml.Serialization.XmlSerializer x = new System.Xml.Serialization.XmlSerializer(resultConversion.GetType());
x.Serialize(myWriter, resultConversion);
}
MessageBox.Show("Fingerprint Stored!");
//------------------------------------------------------------
}
private void OnCaptured(CaptureResult captureResult)
{
try
{
// Check capture quality and throw an error if bad.
if (!_sender.CheckCaptureResult(captureResult)) return;
count++;
DataResult<Fmd> resultConversion = FeatureExtraction.CreateFmdFromFid(captureResult.Data, Constants.Formats.Fmd.ANSI);
SendMessage(Action.SendMessage, "A finger was captured. \r\nCount: " + (count));
if (resultConversion.ResultCode != Constants.ResultCode.DP_SUCCESS)
{
_sender.Reset = true;
throw new Exception(resultConversion.ResultCode.ToString());
}
preenrollmentFmds.Add(resultConversion.Data);
//--------------------CALL METHOD
storePrint(resultConversion);
//
The class DataResult is being referenced, so I can not alter it

UPDATE
If you don't have access to the DataResult<T> class, then you might have to take a slightly different approach and wrap this class with a different, serializable one. You can find a full example here:
How can I XML Serialize a Sealed Class with No Parameterless Constructor?
Previous Answer
The error is clear; you just need to add a parameterless constructor to the DataResult<T> class:
public class DataResult<T>
{
// Add a default constructor (public visibility, no parameters)
public DataResult()
{
// You can still define a method body if you wish,
// no restrictions there. Just don't do anything that
// could jeopardize the (de)serialization.
}
}
As for the implications of adding a default constructor, without knowing what
FeatureExtraction.CreateFmdFromFid(...)
is doing to create the DataResult<Fmd>, it would be impossible to know whether it would cause any issues.

Thanks to Cory, that is a useful answer, however in this example there is another way of serializing using
tempFingerPrint = Fmd.SerializeXml(resultConversion.Data);
this is specific to the Digital Persona SDK

"Use of unassigned local variable" error with an Interface

I'm having trouble with some syntax. I'm not really familiar with interfaces so please excuse my ignorance.
VS2010 is giving me an error at... application.Name = System.AppDomain.CurrentDomain.FriendlyName;
public static void AddApplication(string applicationName = null, string processImageFileName = null)
{
INetFwAuthorizedApplications applications;
INetFwAuthorizedApplication application;
if(applicationName == null)
{
application.Name = System.AppDomain.CurrentDomain.FriendlyName;/*set the name of the application */
}
else
{
application.Name = applicationName;/*set the name of the application */
}
if (processImageFileName == null)
{
application.ProcessImageFileName = System.Reflection.Assembly.GetExecutingAssembly().Location; /* set this property to the location of the executable file of the application*/
}
else
{
application.ProcessImageFileName = processImageFileName; /* set this property to the location of the executable file of the application*/
}
application.Enabled = true; //enable it
/*now add this application to AuthorizedApplications collection */
Type NetFwMgrType = Type.GetTypeFromProgID("HNetCfg.FwMgr", false);
INetFwMgr mgr = (INetFwMgr)Activator.CreateInstance(NetFwMgrType);
applications = (INetFwAuthorizedApplications)mgr.LocalPolicy.CurrentProfile.AuthorizedApplications;
applications.Add(application);
}
I can make that error go away by setting application to null but that causes a run-time null reference error.
Edit:
Here's where I'm adapting the code from. I hope it gives more context
http://blogs.msdn.com/b/securitytools/archive/2009/08/21/automating-windows-firewall-settings-with-c.aspx

You never initialize
application
before using it here:
application.Name = System.AppDomain.CurrentDomain.FriendlyName;
The variable application is defined as:
INetFwAuthorizedApplication application
You need to assign an instance of a class that implements the interface INetFwAuthorizedApplication.
Somewhere there must be one (or probably more) classes in your project that look something like this:
public class SomeClass : INetFwAuthorizedApplication
{
// ...
}
public class AnotherClass : INetFwAuthorizedApplication
{
// ...
}
You need to determine what class you should use (SomeClass, AnotherClass) then assign an appropriate object, e.g. like this:
INetFwAuthorizedApplication application = new SomeClass();

Interfaces are used to describe what an object does, not what it is specifically. To put into "real world" terms, an interface might be like:
ISmallerThanABreadbox with a FitIntoBreadbox() method. I can't ask you to give me "the smaller than a breadbox" ... as that doesn't make any sense. I can only ask you to give me something that "IS smaller than a breadbox". You have to come up with your own object that makes sense to have the interface on it. An apple is smaller than a breadbox, so if you have a breadbox that only holds items smaller than it, an apple is a good candidate for the ISmallerThanABreadbox interface.
Another example is IGraspable with a Hold() method and FitsInPocket bool property. You can ask to be given something that IS graspable that may or may not fit in your pocket, but you can't ask for "the graspable".
Hope that helps...