Question

have a look at this code please:

public void BindElements<T>(IEnumerable<T> dataObjects)
{
    Paragraph para = new Paragraph();

    foreach (T item in dataObjects)
    {
        InlineUIContainer uiContainer =
            this.CreateElementContainer(item.FirstName ????? )              
        para.Inlines.Add(uiContainer);
    }                         

    FlowDocument flowDoc = new FlowDocument(para);
    this.Document = flowDoc;
}

When in write in Visual Studio “item.XXX” I should get the properties from my entitiy like .FirstName or .LastName. I do not know wether dataObjects is an IEnumerable or IOrder etc… it must be generic!

How can I get the real properties form item ? Only with Reflection?

Answer 1

Oded is right, it doesn’t seem (to him or me) to make any sense to try and make this method generic. You are trying to genericize a method whose functionality is actually specific to a few types.

Now, that said, it seems the bulk of the function is independent of this property you want to access. So why not split it into two parts: that which can be genericized, and that which can’t:

Something like this:

void BindElements<T, TProperty>(IEnumerable<T> dataObjects,
                                Func<T, TProperty> selector)
{
    Paragraph para = new Paragraph();

    foreach (T item in dataObjects)
    {
       // Notice: by delegating the only type-specific aspect of this method
       // (the property) to (fittingly enough) a delegate, we are able to 
       // package MOST of the code in a reusable form.
       var property = selector(item);

       InlineUIContainer uiContainer = this.CreateElementContainer(property)
       para.Inlines.Add(uiContainer);
    }

    FlowDocument flowDoc = new FlowDocument(para);
    this.Document = flowDoc;
}

Then your overloads dealing with specific types, e.g., IPerson, can reuse this code (which I suspect may be what you were after all along—code reuse):

public void BindPeople(IEnumerable<IPerson> people)
{
    BindElements(people, p => p.FirstName);
}

…then for IOrder:

public void BindOrders(IEnumerable<IOrder> orders)
{
    BindElements(orders, o => p.OrderNumber);
}

…and so on.