Getting All Test Methodes Names

First of all, you need to define the criteria by which you will distinguish test methods from other methods.

If you are using a special tool/library for testing, like NUnit, or VisualStudio.TestTools.UnitTesting, then this may be relatively easy; if you have created your own testing library, then you would probably create a Custom Attribute to adorn test methods with.

In the case whatever you use doesn't provide a way to get at all the methods easily ... I assume that's the case here ... you are going to select a .dll, or .dll's, and search recursively, using recursion, for Methods that meet your criteria.

A recursive search is going to have this kind of "flow:"

// this is pseudo-code:
foreach FileInfo theFileInfo in AWholeBunchOfDLLFiles

Assembly theAssembly = Assembly.LoadFrom(theFileInfo.FullName);

foreach Type theType in theAssembly.GetTypes()
foreach MethodInfo theMethod in theType.GetMethods()
foreach Attribute attr in Attribute.GetCustomAttributes(theMethod)

// this is an example from working code:
if (attr.GetType() == typeof (YourTestMethodAttribute))
{
    // Bingo !

    YourTestMethodAttribute mta = attr as MyTestMethodAttribute;

    Console.WriteLine
    (
        "Method {0} with MyTestMethodAttribute ID: {1}",
        mInfo.Name,
        mta.ID
    );
}

This is an example of an actual Custom Attribute that would work with the code shown above:

public class YourTestMethodAttribute : Attribute
{
    private static int _id;

    protected int ID
    {
        set { _id = value; }
        get { return _id; }
    }

    public YourTestMethodAttribute()
    {
        ID++;
    }
}