Check an Issue's Field

[Luis Dominguez]

In the workflow, I am trying to create a rule that would prevent an issue from getting marked completed until a certain field is approved. However, this field requires either letter and numbers, but how do I make it require both letter and numbers?

The field is alphanumerical. 

[Trudy Claspill]

What type of field is "Approval of Change Control (CC) Request"? Is it a field where you type in the contents or do you pick from a selection list?

If you are typing in the contents, and what you type in is not strictly numeric, then select Text.

[Luis Dominguez]

It is a custom field that contains letters and numbers for example BIZ12345. If I select text it does not pick up on the numbers. 
How would I write the rule that states: If there are not 10 characters (letters and numbers), then the issue cannot be completed in the workflow?

[Trudy Claspill]

I don't work with Team Managed projects frequently, but I have reviewed the Workflow Rules documentation and experimented with a test project.

Your only options for evaluating the contents of a Text field are "equals" and "doesn't equal". There is no option to evaluate the field content using pattern matching, so I don't believe it is possible for you to determine the length of the field. It appears to me that you have the compare the field contents against a specific and explicit value.