Question

So I have a horribly designed class that I can’t change that has properties like this:

object.Color1
object.Color2
object.Color3

etc…

How can I iterate through those with a for loop. In other words, something like this:

for (int i = 0; i <= 40; i++)
{
   string PropertyName = "Color" + i;

   if (object.PropertyName != "") 
   { 
       // do something
   }
}

Obviously this code wouldn’t work but it gives you an idea of what I’m after. I have to do some processing on each property and I don’t want to repeat my code 40 times. 🙂 A loop would be perfect, I’m just not sure how to create the name of the property on the fly.

EDIT: Ok so I’ve tried the following code:

for (int i = 1; i <= 20; i++ )
            {
                var type = pendingProduct.GetType();

                var colorProperty = type.GetProperty("Color" + i);
                string colorValue = colorProperty.GetValue(type, null).ToString();

                var colorSkuProperty = type.GetProperty("Color" + i + "SKU");
                string colorSkuValue = colorSkuProperty.GetValue(type, null).ToString();

                if (String.IsNullOrEmpty(colorValue)) continue;

                ProductColor color = new ProductColor {Color = colorValue, ProductSizes = productSizes};
                if (!String.IsNullOrEmpty(colorSkuValue)) color.SKU = colorSkuValue;
            }

I’m getting an error “Object does not match target type” on this line:

string colorValue = colorProperty.GetValue(type, null).ToString();

Am I doing something wrong here?

Answer 1

You’re looking for reflection:

PropertyInfo property = typeof(SomeType).GetProperty("Color" + i);
string value = (string)property.GetValue(obj, null);

Note that this will be slow.
If you do it many times, you can make it faster by caching Delegate.CreateDelegate(..., property.GetGetMethod()) in an array.