dynamic person = Model.MediaById(1234);

 @person.phone

I tried the above code , it works fine Umbraco 4.7.1

I can confirm this - a colleague was having the same propblem today. Empty custom properties come back as type DynamicXml rather than (as I would expect) an empty string, null or perhaps DynamicNull.

Steps to reproduce:

Go to Settings > Media Types in Umbraco 4.7.1 back-office. Add a custom TextString property to the Image media type with an alias of AlternativeText. Create an image in the Media folder and leave the AlternativeText field empty. Make a note of the id of the image. Then run this Razor snippet:

var image = Library.MediaById(1055);

<p>
@image.AlternativeText.GetType()
</p>

This returns umbraco.MacroEngines.DynamicXml

This isn't what I would expect and can cause problems when testing for a value which you would expect to be a string. I believe it does the same for other empty datatypes (not just TextString), which also return DynamicXml as the type.

I have done my bit and raised this as Workitem 3054 on Codeplex 

@Dan: Thanks for the help. I have voted on the Workitem on Codeplex, let's hope other do it aswell.

It looks like it is the same problem in 4.7. And also in XLST.

If I do a <xsl:copy> of the media node. I would expect the following

<person>
<phone></phone>
<email>[email protected]</email>
</person>

But instead I get something like this

<person>
<phone>
<email>[email protected]</email>
</phone>
</person>

I have not tested it so much yet. Hope to get som time in the next couple of days

According to Codeplex the bug #30504 has been fixed in 4.7.1. But to me it looks like the bug has returned in 4.7.2.

http://umbraco.codeplex.com/workitem/30847 

Please go vote so it maybe could be fixed in 4.9 

I also ran into problems with this issue #30847, but is there any workarround? How to check if empty DynamicXml "<phone></phone>" is returned?

I am doing it by checking on "<phone></phone>".

But it would be very nice to do a check on ""

I have not yet tried if the "feature" is in 4.8

if you are using razor you can get round this via the has value  helper

in fact I used it to counter a similar problem 

var ageGroupTitle = @AgeGroup.HasValue("PageTitle") ? @AgeGroup.PageTitle : @AgeGroup.Name; 

Ravi

@Ravi Motha sounds like a great work-around. I will try it next time.

I have the same problem with 4.11.6, at least with Media Types and textstring properties.

@psiho please go vote for the bug http://issues.umbraco.org/issue/U4-579 so it can be fixed.

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