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How can I compare a ClassDeclarationSyntax object against an IdentifierNameSyntax object?

I'm writing a source generator in C#, and I've got 2 objects that I need to compare to see if they relate to the same class, but I can't find a way to do it.
My first object is an instance of ClassDeclarationSyntax. This is coming from my custom ISyntaxContextReceiver to find classes that match specific conditions.
Elsewhere in my generator I have an IdentifierNameSyntax object, which is coming from looking at the types within a TypeOfExpressionSyntax that I find within a different class's list of attributes.
I need to compare the two objects here to see if they are talking about the same thing.
With the IdentifierNameSyntax I can get the type information by using the semantic model:
ITypeSymbol semanticType = semanticModel.GetTypeInfo(targetType).Type;
But I don't know how to compare this ITypeSymbol against ClassDeclarationSyntax either.
Is there a way to do this, or is there a way to get the semantic model type information for a ClassDeclarationSyntax object?

The method you are looking for is GetDeclaredSymbol on semanticModel. As you can see from the documentation, there are huge number of overloads which will allow you to get the associated symbol information for not only classes, but also fields, methods, properties, events, parameters, and so forth. Definitely a method you'll want to keep in your back pocket!

Object Serialization to Dictionary per propertyname

I asking this mostly to see if there is something that ressembles what I am trying to achive.
My ultimate goal is to serialize an object graph, keeping references, but making all the properties accessible via a Path of sorts.
My first thoughts were something like dictionary and recursively loop through all the objects properties/fields, and if the value is different than the Default one, try and serialize if its a primitive, otherwise keep going till the type can be serialized.
I need to support Types not marked as [Serializable], and to be able to add custom serialization, similiar to how surrugates work in the BinaryFormatter.
Is there a serializer that works remotely like I said?
Or what other caveats can you think of, by this aproach?
Note: The serialization Size is not a big issue nor is the speed that it serializes/deserializes, at least for now.
An example of what I want to to is something like this :
SerializationContext.GetValue["root/Prop/X"] returns me the X value.
This needs to work with .Net 3.5, and it should serialize based on field/property name.

A change in one object changes the second one too

I'm creating two objects and assign them with a data from IsolatedStorage.
But when I change one object the second one changes too. ( I think the problem may be the pointers are the same, but I can't solve it. )
private ArrayOfClsSimpleData lstUsers;
private ArrayOfClsSimpleData tmpLstUsers;
in class' globals
tmpLstUsers = IsolatedStorageHelper.GetObject<ArrayOfClsSimpleData>("users");
lstUsers = IsolatedStorageHelper.GetObject<ArrayOfClsSimpleData>("users");
The first status of the arrays:
Debug.Write(lstUsers.Count)
Output: 2
Debug.Write(tmpLstUsers.Count)
Output: 2
The counts are the same as expected. But, after I add an item to one list, the other list gets updated too and the counts are still same.
lstUsers.Add(new ArrayOfClsSimpleData());
Debug.Write(lstUsers.Count)
Output: 3
Debug.Write(tmpLstUsers.Count)
Output: 3
EDIT : IsolatedStorageHelper class is something to help to get objects, save object etc. that I do use for simplifying things, so just think it as getting objects from IsolatedStorage.
it is implemented like this:
public static T GetObject<T>(string key)
{
if (IsolatedStorageSettings.ApplicationSettings.Contains(key))
{
return (T)IsolatedStorageSettings.ApplicationSettings[key]; // return the object
}
return default(T); // if key doesn't exists , return default object
}
So it just gets it from IsolatedStorage.
If you don't know isolated storage you can see it from here
So, how can I fix the code so that I can change one without changing the other?

So, basically lstUsers and tmpLstUsers are references to the same object. All you have to do is to create a new one and copy content from the original. If you need a quick solution, then you can do it like this (code below). I just guess that ArrayOfClsSimpleData is some kind of array.
lstUsers = IsolatedStorageHelper.GetObject<ArrayOfClsSimpleData>("myKey");
tmpLstUsers = new ArrayOfClsSimpleData();
foreach (object user in lstUsers) // I don't know the type of objects in ArrayOfClsSimpleData, so I wrote 'object', but you should use the actual type
tmpLstUsers.Add(user);

The problem is that IsolatedStorage is just returning two pointers to the same data. So unless you copy the data, all changes will ultimately be to the same underlying data.
Think of it as two copies of your home address. Anything you change on your home affects all copies of your address since it is just an address and not the home itself.
What you will want to do is clone your object. Built in collections have clone or copy methods built in to do shallow copies, or if you built something yourself you will need to implement it yourself
The easiest way is to implement the IClonable interface and to use the clone method to achieve your copying.
https://msdn.microsoft.com/en-us/library/System.ICloneable.aspx
This basically involves going through and calling member wise clone for each complex object (which will copy all value types for you)
https://msdn.microsoft.com/en-us/library/system.object.memberwiseclone.aspx

I don't think cloning is necessary. Just create a new list instead of operating on the same instance. You can do that by calling ToList() on the returned instance:
lstUsers = IsolatedStorageHelper.GetObject<ArrayOfClsSimpleData>("myKey").ToList();

Can't you use the Clone() method of IClonable while fetching the object? looks like both list objects are getting same reference objects.

Create object names dynamically

I am building web service in C# for a particular application, I have a XML definition of module. I have created a class called Field that holds the properties of all fields on a module. What I would like to do is create the field objects but name them dynamically then add them to a list of some sort. So when I reference them from the client it would be like this:
Module.Fields.MyDynamicName.FieldProperty
Is this possible to do? and could anyone point me in the right direction on how to do this.
Hope my question makes sense.

Basically you need to design for "deferred design", which means you do not know at compile time what the design is, but you still need to accommodate it.
There are probably a few ways but what I have done in the past is use a dictionary list of Key/Value pairs to store fields. Using serialization (I prefer Json) you can shove just about anything into a string and store it as the Value, then deserialize it when you need it.

Creating objects driven by the database to populate a Treeview - very slow

I have an application that reads a table from a database.
I issue an SQL query to get a result set, based on a unique string value I glean from the results, I use a case/switch statement to generate certain objects (they inherit TreeNode BTW). These created objects get shunted into a Dictionary object to be used later.
Whilst generating these objects I use some of the values from the result set to populate values in the object via the setters.
I query the Dictionary to return a particular object type and use it to populate a treeview. However it is not possible to populate 2 objects of the same type in a treeview from the Dictionary object (you get a runtime error - which escapes me at the moment, something to with referencing the same object). So what I have to do is use a memberwiseClone and implement IClonable to get around this.
Am I doing this right? Is there a better way - because I think this is causing my program to be real slow at this point. At the very least I think its a bit clunky - any advice from people who know more than me - greatly appreciated.

Is there a reason you are using the external dictionary? I would populate the tree directly as the data is queried.
If you do require the dictionary, you could set the .Tag property of the tree node to point to the data in your dictionary.

To add to #Brad, only populate the tree as needed. That means hooking into the expand event of the tree nodes. This is similar to how Windows Explorer functions when dealing with network shares.
There should be 1 TreeNode object per actual tree node in the tree - don't try to reuse the things. You may either associate them with your data using the Tag property (this is the recommended method), or you can subclass the TreeNode itself (this is the Java method, but used less in .NET).
(The use of cloning methods is usually a hint that you're either (a) doing something wrong, or (b) need to factor your domain model to separate mutable objects from immutable.)

have you considered using a Virtual Tree view which only loads the nodes the user actually wants to look at - i've had good success with the component from www.infralution.com