Bug 41512 - [PlainString] attribute doesn't work on parameters on protocol methods
Summary: [PlainString] attribute doesn't work on parameters on protocol methods
Status: CONFIRMED
Alias: None
Product: iOS
Classification: Xamarin
Component: Xamarin.iOS.dll (show other bugs)
Version: XI 9.8 (tvOS / C7)
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Future Cycle (TBD)
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2016-06-05 00:51 UTC by Israel Soto [MSFT]
Modified: 2016-07-19 13:40 UTC (History)
3 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:

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Status:
CONFIRMED

Description Israel Soto [MSFT] 2016-06-05 00:51:31 UTC
Created attachment 16197 [details]
[PlainString] usage sample

When you are binding an Objective-C class method with `const char *` as parameter, you need to add [PlainString] attribute to C# parameter so, when you pass a string, it passes, literally, a string and not the reference of a NSString.

```
// @interface CStringTest : NSObject
[BaseType (typeof (NSObject), Name = "CStringTest")]
interface CString
{
	// - (void)CStringMethodWithMessage:(const char *)message;
	[Export ("CStringMethodWithMessage:")]
	void CStringMethod ([PlainString] string message);
}
```

But when you have a protocol method with `const char *` as parameter and you add [PlainString] attribute to C# parameter, it compiles but it crashes at runtime:

```
// @protocol CStringDelegate <NSObject>
[Model]
[Protocol]
[BaseType (typeof (NSObject))]
interface CStringDelegate
{
	// @required - (void)CStringRequiredMethodWithMessage:(const char*)message;
	[Abstract]
	[Export ("CStringRequiredMethodWithMessage:")]
	void CStringAbstractMethod ([PlainString] string message);
}
```

Does this is a bug?

I attached a sample that has the Xcode project, Binding project and a sample that reproduce the bug.

Greetings,
Israel Soto
--
Comment 1 Alex Soto [MSFT] 2016-06-07 05:54:51 UTC
> Does this is a bug?

Yes, you found a missing feature, thanks for the report! I can reproduce it with the test case you provided.