I've written a custom attribute that I use on certain members of a class:
public class Dummy
{
[MyAttribute]
public string Foo { get; set; }
[MyAttribute]
public int Bar { get; set; }
}
I'm able to get the custom attributes from the type and find my specific attribute. What I can't figure out how to do is to get the values of the assigned properties. When I take an instance of Dummy and pass it (as an object) to my method, how can I take the PropertyInfo object I get back from .GetProperties() and get the values assigned to .Foo and .Bar?
EDIT:
My problem is that I can't figure out how to properly call GetValue.
void TestMethod (object o)
{
Type t = o.GetType();
var props = t.GetProperties();
foreach (var prop in props)
{
var propattr = prop.GetCustomAttributes(false);
object attr = (from row in propattr where row.GetType() == typeof(MyAttribute) select row).First();
if (attr == null)
continue;
MyAttribute myattr = (MyAttribute)attr;
var value = prop.GetValue(prop, null);
}
}
However, when I do this, the prop.GetValue call gives me a TargetException - Object does not match target type. How do I structure this call to get this value?
Your need to pass object itself to GetValue, not a property object:
var value = prop.GetValue(o, null);
And one more thing - you should use not .First(), but .FirstOrDefault(), because your code will throw an exception, if some property does not contains any attributes:
object attr = (from row in propattr
where row.GetType() == typeof(MyAttribute)
select row)
.FirstOrDefault();