Tag Values are empty or zero

[Marco Ribolla]

I have designed four classes (Patient, Study, Series, Image) which should hold the information of the related tags.

First I tried to read the private tag values like this:

var tag = DicomTag.Parse("2001,107B");

var value = file.Dataset.Get<string>(tag);

and this:

var tag = DicomTag.Parse("2001,107B");  

var item = (from dicomItem in file.Dataset

            where dicomItem.Tag.Group == tag.Group &&   dicomItem.Tag.Element == tag.Element

            select dicomItem as DicomElement).SingleOrDefault();

var value = item==null?string.Empty:item.Get<string>();

and this:

var value = file.Dataset.Get<string>(file.Dataset.GetPrivateTag(DicomTag.PatientBirthName));

All of them returned me null / an empty string, but I don't really understand this result. My file isn't null (otherwise --> exception) and that tag can't be empty. Can you eventually explain me the possibilities of this occurence and how to solve it?

Thank you

[Marco Ribolla]

Finally I've found my mistake:

wrong: var value = file.Dataset.Get<string>(file.Dataset.GetPrivateTag(DicomTag.PatientBirthName));

right: var name = file.Dataset.Get<string>(DicomTag.PatientID);

Can it be, that with the second alternative it works only because the DicomTag isn't private? Is possible to get values from private tags?

[MENG HO]

I have the same issue, too. I keep looking for a way to read private tag and change the value. But no luck for fo-dicom. I ended up with using other DICOM toolkit to read it. But really want to know how to do it with fo-dicom.

[Chris Horn]

check out https://groups.google.com/forum/#!searchin/fo-dicom/private$20tags/fo-dicom/2Sgvui0pJRc/dsp5IBRZIAMJ
and https://groups.google.com/forum/?fromgroups#!searchin/fo-dicom/private$20tag/fo-dicom/4BH1c4STHro/0ZEgFb8vrx4J

for reading normal tags

var name = file.Dataset.Get<string>(DicomTag.PatientID);

Also check out the https://github.com/fo-dicom/fo-dicom/blob/development/ConsoleTest/Program.cs towards the bottom of the file