Converting GUID to String via Reflection

Question

Hi There,

I'm using Reflection to set a property value via PropertyInfo.SetValue(); The property in question is a string, and the object from which I'm getting the value is actually a GUID. I'd like to convert from a GUID to a string in the process - is there any way of defining some kind of implicit cast which will enable this? At the moment I'm getting an error:

"Object of type 'System.Guid' cannot be converted to type 'System.String'."

I guess I could do a type check and manually convert if necessary, but if there's an elegant way of doing it behind the scenes then that would be preferable!

Many thanks.

---

Edit: I can't really just call the .ToString() method on a GUID as I'd very much like my code to look like this:

propertyInfoInstance.SetValue(classInstance, objectWithValue, null)

where objectWithValue is an int/bool/string/GUID. This works fine for everything except a GUID, as (I think!!) there's an implicit cast available. I could do a type check beforehand and just convert the GUID to a string, but I just get that "There must be a better way..." feeling.

Answer 1

I don't believe there is an implicit cast between string and guid. Try this:

guid.ToString();

For question 2:

if(propertyInfoInstance.PropertyType == typeof(string) && objectWithValue != null)
{
    objectWithValue = objectWithValue.ToString();
}
propertyInfoInstance.SetValue(classInstance, objectWithValue, null);

I don't think it's too messy.

Answer 2

It's my understanding (someone please correct me if this is wrong,) that you can only define implicit cast operators for your own objects.

You'll need to manually handle dumping the GUID to a string w/ guid.ToString();

Answer 3

Have you tried .ToString() on the GUID reference?

Answer 4

You can write something like this:

object myValue = /* source the value from wherever */;
if (!(myValue is string)) myValue = myValue.ToString();

Then call the PropertyInfo.SetValue() with myValue.