Crystal Reports - Default Parameters

Question

In Crystal reports, you can define default values for the report parameters.

For example, I might have a date range and set a default start of 12/01/2008 and a default end of 12/31/2008.

Is it possible to modify these defaults at runtime? For example:

1 - Default to the first and last days of the current month?

2 - Default to the first and last days of a proprietary company fiscal calendar? (i.e., look it up in a database)

3 - First & Last days of the current year?

You get the point. Is this possible? I'd even be open to a solution that involved running an external application to reach into the reports and modify them, if anyone knows how to do that.

Edit:

To answer the question posed by Philippe Grondier, most of these reports are run from inside an application. I was hoping for something simpler than manipulating the crystal object at runtime; I have my hands full right now with figuring out other parts of that API. I might take a look in the future, though.

Answer 1

Are you planning to run your crystal report from the crystal reports interface or as an add-in embedded in another program (you can for example use the Crystal Reports ActiveX Designer Runtime Support - craxdrt.dll - in VB code) ? In this last case, it is possible to manipulate every object of the report before launching it. Objects such as parameters can then be updated according to your needs.

As a simple example of such runtime update, my report printing routine will allways check if there is a field named "printedBy" in the report. In case this field is found, its value will be settled to the the domain name of the user that requests the report and will be printed out.

At an higher level, you can even reshape the report SQL string to add specific filters that can be inherited from your code. By doing so you might not even need parameters anymore: let your code add the filtering values 'on the fly'

EDIT: some code examples:

(m_rapport is a CRAXDRT.report object, ActiveSession is my current session object)

If m_rapport.ParameterFields.Count > 0 Then
    For i = 1 To m_rapport.ParameterFields.Count
        If m_rapport.ParameterFields(i).Name = "{?PUB_DateDebutPeriode}" Then
            m_rapport.ParameterFields(i).AddCurrentValue CDate(DateValue(sessionActive.dateDebutPeriode))
        End If
        If m_rapport.ParameterFields(i).Name = "{?PUB_DateFinPeriode}" Then
            m_rapport.ParameterFields(i).AddCurrentValue CDate(DateValue(sessionActive.dateFinPeriode))
        End If
        If m_rapport.ParameterFields(i).Name = "{?PUB_id_Personne}" Then
            m_rapport.ParameterFields(i).AddCurrentValue StringFromGUID(clientActif.id_Personne)
        End If
    Next i
Endif

I also have another function to change report's datasource at runtime, so that reports can be executed on different servers/locations.

Answer 2

Read my posting Crystal Reports: Named-Date-Range Parameters. Maybe you'll be able to leverage this technique for your purposes.