Why are stored proc params being passed NULL?

[brailian]

VB6, RDC, ODBC, SQL Server

This is probably very easy, I'm just new to RDC (been using OCX for years)

I have a VERY simple report using ODBC, based on a stored proc with 1 char param. It works fine in the Crystal Designer.

In VB6, I add the viewer to a form and add this code:

Private Sub Form_Load()
Dim app As CRAXDRT.Application
Dim myReport As CRAXDRT.Report

Set app = New CRAXDRT.Application
Set myReport = app.OpenReport("c:\work\xtest.rpt&quot
myReport.Database.Tables(1).SetLogOnInfo "MyDSN", "MyTable", "sa", "MyPwd"
myReport.ParameterFields(1).AddCurrentValue "TheValue"
myReport.EnableParameterPrompting = False

CRViewer1.ReportSource = myReport
Form2.WindowState = vbMaximized
Form2.Show
myReport.DiscardSavedData
CRViewer1.ViewReport
End Sub

No error occurs, but the report shows no data. The stored procedure is being passed NULL instead of "TheValue" (I did a trace to confirm).

What am I doing wrong?

Note: If I don't set EnableParameterPrompting = False, then crystal prompts for the value and if I type it in, it gets passed properly. (again, confirmed with trace)

 

[StevenK]

I set the values of parameters as required through Delphi code using the syntax :
CRReport.ParameterFields[1].SetCurrentValue('The Value', crStringField);
... that's assuming that it is a String Field you're dealing with.
Hope that this helps.
Steve

 

[MeTheZayets]

if there is only one parameter then the parameter field is
ParameterFields(0) not ParameterFields(1)

 

[brailian]

Actually, it is 1 not 0. You are probably thinking of the API. The RDC appears to be 1-based. And like I said, it doesn't give an error, it just passes NULL to my stored procedure.

 

[StevenK]

I make use of the 'SetCurrentValue' rather than 'AddCurrentValue' or is this the equivalent in VB as compared with Delphi ?
Are you able to use 'SetCurrentValue' ?
Steve

 

[brailian]

Actually, VB Intellisense did not reveal that there was a SetCurrentValue method, so I was using the AddCurrentValue method instead which appears to do the same thing. However, when I typed out SetCurrentValue, it accepted it. Same problem, though.

However, I just solved it. On a hunch I moved the DiscardSavedData method call above the code to set the parameter value and that fixed it! Why??? I have no idea. Weird, I wouldn't have thought SavedData had anything to do with the new data.