Free Support Forum -

Aspose.Tasks ExtendedAttribute.AttributeDefinition Always Null

I am trying to identify which ExtendedAttribute I am looking for by looking at the AttributeDefinition.FieldName but the AttributeDefinition is always null?

I am using your latest build of the


The AttributeDefinition.FieldName has to work for MSP 2003 mpp files. For MSP 2007 mpp files you can use AttributeDefinition.Alias now:

ExtendedAttribute attr = task.ExtendedAttribute[0] as ExtendedAttribute;
if(attr.AttributeDefinition.Alias == “MyText1”)

For MSP 2003 all types of extended attribites are supported in v. For MSP 2007 durations and flags extended attributes are added in next Aspose.Tasks 2.5.0 release. FieldName support for MSP 2007 mpp files is planned too in the next release. For MSP XML format the support was added for long time.

No I cannot access any of the examples you have provided because the object AttributeDefinition is null

So trying to access the property Alias or FieldName will throw a null exception regardless of using a mpp or xml file

I have included a small sample file. The ExtendedAttribute I am trying to find is the Text3 or "SCR #"


Thank you for the sample. Now I can understand the problem. Now Aspose.Tasks can read extended attributes when they are defined as in In that case they have to be defined as custom fields (see or outline codes.

In your case, the Text3 column was added to the Gantt chart view and renamed (SCR# is the column name and not the extended attribute Alias).

I have updated your file as follows: A custom field Text3 with Alias 'SCR #' was created and its values were defined for each task. See the file and task's properties screen shot in the attachment. In this case Aspose.Tasks has to read the extended attribute definitions and values.

I will analyze how we can read the extended attributes' definitions in your case and then I will create an issue.


I am currently focusing on the Project XML functionality. However, I did try to read one of the MPP files created from a XML file. I did not find any EAD objects when loading with Aspose.Tasks. I did check that all of the extended attributes are actually in the file. This makes me think that the EADs are actually in the file. (I have a routine that checks for 5 defined EADs - If they don't exist, they are created. In some ways, this masks the problem as I just make the EADs rather than report an error.) I believe the EADs are coming through on the XML.


Regards, Bruce

Thanks for the detailed explanation. That was very helpful. I am obviously not one that works with MSProject but just a developer that needs to work with its data


Your information is very helpful and the subject is an our bug, of course. The sample you provided helps us find a second way to create extended attributes without custom field which we did not put into account while the feature was developing. And I think the second way is common in case when you just need to add some custom data without any aliases, values list and so on.

Thank you a lot for your information. Your posts REALLY help make our product better!

The issue ‘Reading extended attrubute definitions for attributes without custom fields.’ with issue id 13727 was created and linked to this forum thread.

Sorry for inconvenience.


For MSP 2003 mpp files the issue has been fixed in the new Aspose.Tasks 2.5.0 release. For MSP 2007 it is still under development.

The issues you have found earlier (filed as 13727) have been fixed in this update.

This message was posted using Notification2Forum from Downloads module by aspose.notifier.

The issues you have found earlier (filed as ) have been fixed in this Aspose.Words for JasperReports 18.3 update.