Archive for November, 2014

Cannot convert null to ‘System.Guid’

I was trying to pass a GUID into a function. When declaring the GUID, I set it to null because it was going to be populated in the method:

Guid customerId = null;
if (ValidateUser(string userName, ref customerId))

At the declaration line, I received the error “Cannot convert null to ‘System.Guid’ because it is a non-nullable value type”. To resolve this, I set the Guid to Guid.Empty instead of null:

Guid customerId = Guid.Empty;

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