My next major task is to implement ASP.NET MVC and figure out how it works. However, I have come to understand that reflection is incredibly useful in figuring out how things work so I have digressed. 

From the first reflection tutorial I tried:

The First Experiment

This code:

rosters_studentsDataContext gridData = new rosters_studentsDataContext()

Type testType = gridData.GetType();
 Response.Write("testType=" + testType);



And does not requires a "using namespace" reference.

The Second Experiment

This code:

            MethodInfo testMethodInfo = testType.GetMethod("helloWorld");
            Response.Write("<BR>testMethodInfo=" + testMethodInfo);


testMethodInfo=System.String helloWorld(System.String) 

But does require adding a namespace directive:

using System.Reflection;

Also note that the object against which the GetMethod is applied is the Type object produced by the first step, testType.

The Third Experiment

This code:
            string[] invokeData = new string[] {"reflection invoke"};
            var testResult= testMethodInfo.Invoke(gridData, invokeData);
            Response.Write("<br>invocation result="+testResult);


invocation result=reflection invoke says, Hello World 

Note that 1) invoke is applied to the method that was extracted from the type, 2) an instance of the class was passed to invoke and 3) the test data has to be an array (I tried every simpler version). (ps, As you can see from the second experiment, the definition of helloWorld() is that it takes a string but, invoke needs an array to pop it off of.)

Moving right along to a different person's view of a reflection tutorial, I try these things:

The Fourth Experiment

This code:

            ConstructorInfo[] info = testType.GetConstructors();
            foreach (ConstructorInfo cf in info) { Response.Write("<br>Constructor=" + cf); }


Constructor=Void .ctor()
Constructor=Void .ctor(System.String)
Constructor=Void .ctor(System.Data.IDbConnection)
Constructor=Void .ctor(System.String, System.Data.Linq.Mapping.MappingSource)
Constructor=Void .ctor(System.Data.IDbConnection, System.Data.Linq.Mapping.MappingSource) 

SInce I am using a LINQ generated class, this is sensible though it does make me realize that the idea of a constructor is different in C# than in PHP. Note that this is executed against the Type object, testType.

The Fifth Experiment

This code:

            MethodInfo[] info2 = testType.GetMethods();
            foreach (MethodInfo cf in info2) { Response.Write("<br>Method=" + cf); }


Method=System.String helloWorld(System.String)
Method=System.Data.Linq.Table`1[roster] get_rosters()
Method=System.Data.Linq.Table`1[student] get_students()
Method=Void Dispose()
Method=System.Data.Common.DbConnection get_Connection()
... and another jillion more like them

Again, the LINQ generated class has a lot of stuff in it. Note that my helloWorld() method shows up nicely though, at the beginning where I put it. It's also interesting that there are many of these that do not appear in the class definition file, eg, Dispose(). The class is opened with a lot of "using" declarations and then, "public partial class rosters_studentsDataContext : System.Data.Linq.DataContext". I'm guessing that a lot of those are in that DataContext stuff but, it won't let me open it. Perhaps that will be another day's reflection experiment.

And to put a Bow on it, I wrap up with the obvious, but absolutely necessary

This code:

            PropertyInfo[] info3 = testType.GetProperties();
            foreach (PropertyInfo cf in info3) { Response.Write("<br>Property=" + cf); }


Property=System.String tqTestVar
Property=System.Data.Linq.Table`1[roster] rosters
Property=System.Data.Linq.Table`1[student] students
Property=System.Data.Common.DbConnection Connection
Property=System.Data.Common.DbTransaction Transaction  
... and another jillion more

OK, so the bottom line is this:

Given the addition of System.Reflection to an assembly (another thing whose definition I need to nail down), you can crack open the class and operate on it. There are methods to extract the components of classes and methods to activate them (I only tried invoke() today but there are more, I'm sure).

Tomorrow, I think I will try to figure out how to set a property and how to reflect upon System.Data.Linq.DataContext.