Using parameters in reports for VIsual Studio 2008
This is my first attempt to create a Visual Studio 2008 report using parameters. I have created the dataset and the report. If I run it with a hard-coded filter on a column the report runs fine. When I change the filter to '?' I keep getting this error:
No overload for method 'Fill' takes '1' argument
Obviously I am missing some way to connect the parameter on the dataset to a report parameter. I have defined a report parameter using the Report/Report Parameter screen. But how does that report parameter get tied to the dataset table parameter? Is there a special naming convention for the parameter?
I have Googled this a half dozen times and read the msdn documentation but the examples all seem to use a different approach (like creating a SQL query rather then a table based dataset) or entering the parameter name as "=Parameters!name.value" but I can't figure out where to do that. One msdn example suggestted I needed to create some C# code using a SetParameters() method to make the connection. Is that how it is done?
If anyone can recommend a good walk-through I'd appreciate it.
Edit: After more reading it appears I don't need report parameters at all. I am simply trying to add a parameter to the database query. So I would create a text box on the开发者_运维百科 form, get the user's input, then apply that parameter programmatically to the fill() argument list. The report parameter on the other hand is an ad-hoc value generally entered by a user that you want to appear on the report. But there is no relationship between report parameters and query/dataset parameters. Is that correct?
My last assumption appears to be correct. After 30 years in the industry my bias is to assume a report parameter actually filters the SQL data using the given parameter. This is not the case with .rdlc files used by Report Viewer. These report parameters have nothing to do with fetching data. Sounds like this was a design decision on Microsoft's part to completely separate the display of data from the fetching of data, hence, Report Viewer has no knowledge of how data may be fetched. Best way for me to conceptualize this dichotomy is to think of Report Parameters more as Report Labels, quite distinct from the dataset query parameters.
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