[C# Crystal Reports 2008] How to change 'Sum' condition at runtime?

Question

My report Groups by two fields, the second being a date field.

If I go to 'Group Expert', select the second field (the date field), and click Options, I get the 'Change Group Options' dialog. There are two tabs (Common and Options), on the Common tab we now see three comboboxes.

Combobox1: The Date field

Combobox2: in ascending order.

And the third comobox, which exists because this is a date field, has this label above it: "The section will be printed:"

And its value is:

Combobox3: for each day.

OK. In my Formula Editor, I need to sum a field (within our group by field), so my formula looks like this:

Sum({Table.Field}, {Table.OurDateFieldWeAreGroupingOn}, "daily")

Daily is there because Group Expert is "for each day". If I change ComboBox3 to "for each month", the string in the Sum function would have to change to "monthly". The Sum function is there so that I have a running total every time crystal reports breaks on my grouping.

The issue I am running into is the string condition. This is because I want to be able to change the grouping at runtime.

For example,

switch (grouping)
{
    case Minute:
        m_Rpt.DataDefinition.Groups[1].GroupOptions.Condition = 9;
        break;
    case Hour:
        m_Rpt.DataDefinition.Groups[1].GroupOptions.Condition = 10;
        break;
    case Day:
        m_Rpt.DataDefinition.Groups[1].GroupOptions.Condition = 0;
        break;
    case Week:
        m_Rpt.DataDefinition.Groups[1].GroupOptions.Condition = 1;
        break;
    // etc, etc, etc
}

So, they allow me to change the grouping at runtime, no problem. At design-time I had "daily", but I could make it "monthly" (for example). Btw, does anybody know if I can replace the 9, 10, 0, 1, etc. with some Crystal Reports defines (something from an enum or something)? I only figured out that "weekly was 1" (for example) because that was the 2nd item in "combobox3".

Being that I can change this at runtime? How the heck can I modify the condition of my formula?

If I changed it, at runtime, to weekly, I'd need my Sum to look like this:

Sum({Table.Field}, {Table.OurDateFieldWeAreGroupingOn}, "weekly")

The problem is that in the field editor, if I use anything other than a string, I get this error: "A group condition must be a string". I had tried to pass that string as a value (for example):

Sum({Table.Field}, {Table.OurDateFieldWeAreGroupingOn}, {@ValuePassedIn})

I mean, if they allow you to change the grouping at runtime, I have to be able to change the conditions of the formulas too, right?

Answer 1

I'm basically learning Crystal Reports on the fly, so some things might escape me at the moment ... that being said:

The Sum field was originally used because I needed to maintain a "running total" every time that the page breaks on my grouping. Well, I went ahead and crated a "Running Total" field (which doesn't require me to specify daily or weekly or monthly). Then, in my formula, I used this new Running Total field instead of the Sum function (they both did the same thing).

Problem solved.