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Dynamically create a class and then create a list<dynamicClass> based on it in C#

I want to create a class and its properties on run time, the properties will be like Year2001, Year2002, Year2003, Year2004, Year2005... I get these property names on run-time, I get them in a list. Later I need to use this class to create a list which I need to show in the kendo grid.I surfed a lot and thought of using ExpandoObject, but was unsuccessful.

If all properties will be of the form YearX and contain some information about or related to that year, then I would strongly recommend you (if at all possible) to go with something along the lines of an IList<YearInfo> where YearInfo is some object containing the info you need for every year, including an integer property indicating what year the object corresponds to. If you require these objects to be unique you could use an IDictionary<int, YearObject> or ISet<YearObject> instead.
Reflection can be powerful, but it it comes at the price of complexity and loss of type safety/compile-time checks. Avoid when possible.

Sounds to me like you are really wanting to a grid with grouping support. Your idea of having the system create a CLASS at runtime is not going to fly. Even if it were possible, which I doubt it is, it is absolutely the wrong approach.
Like I say - have a read about Grouping / Hierarchy on Grid Controls (Kendo grid example here), and maybe have a look at OLAP cubes as well...

Although you have had some answers I would also like to suggest an alternative way of doing this which is using DataTables. This is the approach I take when I have any "Dynamic" data sets that I want to present to the grid.
This is also the approach that Telerik themselves take with one of their code samples.
here are a couple of links to show them doing this to DataTables and Dynamic Objects
Grid Binding to Data Table
Grid Binding to Dynamic Objects
Personally I find the binding to Tables easier to deal with as I am used to dealing with Data Tables.

Set the required field based on particular conditions

Is it possible to indicate a property is a required field without using data annotation attributes?
Instead of using annotation attributes, I want to set it as a required field, based on particular conditions.
For eg, something like below
if (true)
{
//set myObj.Name as required field
}
Edit: The reason why I need to do is, I'm calling a business service class of our own framework, which I can not touch, and inside the class, when the entity is being saved, mandatory checking is already catered.
But, in my requirement, I need to save my entity several times and , each times, the mandatory checking may be different . That's the reason why I need to mark the properties required fields dynamically.
Otherwise, I have to made my own mandatory checking before calling the business service class, which I don't want to do.

From your description, it seems like you need to provide your "own mandatory checking". I say this for two reasons;
To provide your user meaningful feedback as to why something field is required
Also, to satisfy the contract of your business service class
Can you have a "validate" method that simply runs through your set of rules (that mandatory checking, that you mentioned earlier) and have it return a list of strings indicating the rules that were violated on an attempt to save. Then you can use these strings to populate the text of a message box, logfile or whatever to provide meaningful feedback to the user as to why something wasn't saved, and also ensuring that data that is saved, is compliant to your business service class.

.Net/C# Reflection--Populating ComboBox

Greetings all,
I have a list of "Types" meeting a certain critera that I obtained through reflection. Each of the types is a different feature that the user will potentially choose at runtime. If I add more subclasses later, this dynamic implementation would save my having to remember to update the user control is the idea here.
The list of types is nice, but it'd be nice to display something more meaningful than the Name as it's written in code. For example, instead of "RacingBikeDesigner", I'd like to display "Racing Bike Designer", and maybe even display other properties associated with that type like "Description" so that the user knows what that particular choice does.
So I guess the question is, given a Type, how can I provide a more meaningful representation to the user? Could I maybe add a static field to each subclass and call that from the Type, or could I perhaps use a type converter somehow?
The user control (ListBox, ComboBox, etc) is bound to the return value below, but it's not user-friendly:
List<string> LeftHandedUserChoices = new List<string>();
Type[] AllTypesInThisAssembly = Assembly.GetAssembly(typeof(UserChoices)).GetTypes();
foreach (Type _currentType in AllTypesInThisAssembly)
if (_currentType.IsSubclassOf(typeof(UserChoices)))
LeftHandedUserChoices.Add(_currentType.Name);
return LeftHandedUserChoices;
Cheers,
Q

You have a couple of options for doing this. You could use an attribute on your type for the description, or put it in a static field/property on the Type and retrieve that using reflection.
If localization is an issue, you will probably want to store the resource string name, and display the resource value at runtme.

Add custom C# Attributes to your types.

One method is for you to parse class names based on the naming convention you are using (looks like Pascal in your case). For instance RacingBikeDesigner will become Racing Bike Designer. Here is a parsing example.

View model properties has changing validation rules at run time

I'm new to C# MVC and I'm trying to add some dynamic validation checks to my view models that are used in a form. For example, I have a string property called FirstName. I can add the attribute StringLength(10) and Required() to it.
My problem is, depending on some other field, the FirstName StringLength could vary from 10 to 20, etc. I still want to use the MVC validations but be able to modify it. I know that attributes are bound to the class so maybe I'm using the wrong thing.
I want the abilities for attribute validation but have it modifiable at run time. Is this possible?

The values in an attribute have to be literals. You can still use attribute based validation, but you will need to use the CustomValidation tag and point it at a method to use. If it depends on multiple fields in the object, you will want to put this on the class rather than the property.

It seems you can add validation attributes at runtime by implementing DataAnnotationsModelValidatorProvider:
Dynamic Attributes # forums.asp.net

How can I convert an XML structure to a defined object?

I am accessing a service and I get returned an object in the form of (for example)
Car _car = _service.FetchCar(carId)
Car.Color
Car.Tires.Right.Front
Car.Tires.Left.Front
Car.Tires.Right.Back
Car.Tires.Left.Back
Car.Spoiler
etc, etc...you get the idea. My application is recieving many different objects with many differen structures. What I'd like to do is to be able to have one method that would be able to take one type of object and map it to another...
What I don't want to have to do is to manually map all the fields from the service object to my domain object with every object type
for example
If I get a Car object from the service I'd like to map it to my own Car object and if I get a Table object I'd like to map it to my own table object
any ideas?

Have a look at tools like AutoMapper to handle these "copy all fields from object A to object B" scenarios.
AutoMapper will automatically copy all fields with identical names from one instance to the other, and you can set up additional rules to allow copying of fields where the names don't match (and you can also define custom converters if you need to convert data types along the way).
Very useful, very helpful!
Marc