Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

C# C# Streams and Data Processing Parsing Data Working with DateTime

Ranvir Sahota
Ranvir Sahota
9,844 Points
Posted by Ranvir Sahota
Ranvir Sahota
9,844 Points

Why can't a property be used in out for TryParse?

I tried to do it in visual studio and it came up with an error "A property or indexer may not be passed as an out or ref parameter." https://stackoverflow.com/questions/27085696/autoproperty-as-out-value So far the top answer is the best explanation I've seen so far. I would like to get a second opinion and hear if anyone else has any idea why they did this. Thanks

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

The SO explanation seems to cover it. An out (or ref) needs to be associated with a place to store something but a property represents a set of methods for getting and setting a value. So there's really nothing the compiler can do to make this work. But it's easy enough to get around, for example, assuming an int type:

int result;
if (int.TryParse(MyString, out result))
    MyProperty = result;
Ranvir Sahota
Ranvir Sahota
9,844 Points
Ranvir Sahota
Ranvir Sahota
9,844 Points

ok thanks, I was reading through some c# documentation to help my understanding and you can do this now in 7.0:

if (int.TryParse(MyString, out int result)) MyProperty = result;