How to Insert conditional hyperlink in Crystal Reports

I have Crystal reports, and I'd like to modify a field to be a hyperlink, depending on another field. But the other field may or may not have data. How do I define the field?

Fields: IDNumber, LinkField

If LinkField is not NULL, show IDNumber as its own value, with a underline and hyperlink set to LinkField. If LinkField is NULL, then just show IDNumber as itself, with no hyperlink.

So, if the report had three IDNumbers, and only the second had a hyperlink, starting with data (3455, NULL; 4933, http://nothing; 4939, NULL)

It would look something li开发者_JAVA百科ke the following:

3455

4933

4939

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I could make a field that had a value and another field with the hyperlink. The hyperlink field was suppressed but on top of the field with the value. That worked from within Crystal Developer, but not when it was moved to our server.

Since I was short of space, I tried displaying just part of the link. That worked both in development and on the server, but I was ultimately wishing to print the files to PDF and maintain the links. The links in the PDF only worked if they showed entirely.

I eventually had to show the entire link in the report, giving it a separate line (to make room). (I also tried printing it in 1 point font, which did make it look like an underline, but that was hard to click on and also still overwrote fields.)