Adding components to a GameObject referenced within code

Question

So in my project, I have a class called ComponentRegistry. The idea of this class is to store a dictionary of components and their names. For example:

    public Dictionary<string, MonoBehaviour> registry;
    public MonoBehaviour testComponent;

    void Start(){
        registry = new Dictionary<string, MonoBehaviour> ();
        registry.Add ("TestComponent", testComponent);
    }

    public MonoBehaviour GetScript(string name)
    {
        return registry[name];
    }

Then in a separate class, I will access this dictionary using a string in order to retrieve the associated component, subsequently adding the associated component to the gameObject.

    foreach (string comp in blockInfo.components) { 

    //For each of the components that need to be added

        gameObject.AddComponent(ScriptMaster.compReg.GetScript(comp)); 

        //I know this is incorrect, but the idea is there
}

Just for understanding, compReg is an instance of the ComponentRegister class stored as a static variable within my ScriptMaster class.

But no matter what I try, I have not been able to get this to work. I have switched endlessly between different formatting of adding components to gameObjects, alternating between using Components and MonoBehaviours, adding by type.

Thank you for any insight.

Answer 1

You probably wanted to create new instance of said script instead of passing reference to an existing instance. In order to do that, you can either implement the Factory pattern, or one of the IConeable variations/semantics - which would also allow you to have several "default" settings of one script.

Alternatively, if you need just "get an instance by type name" semantics, you can use the Activator.CreateInstance():

//you should be able to get the correct name by typeof(T).FullName 
// or instance.GetType().FullName 
foreach (string compTypeName in blockInfo.components)
  gameObject.AddComponent(Activator.CreateInstance(null, compTypeName ).Unwrap());