Btrieve C# Extra Operations

[larrym5353]

I have a Btrieve application and want to expose some of the data as VS.NET Datasets. I have the Btrieve C# sample from Pervasive.

What I don't understand about the sample is what they do to call the Equal Record API. Specifically they first call First_Record + 50. If that is okay they call Equal_Record + 50 with a blank key. If that is okay then they fill in the correct key and call Equal_Record. If that is okay then they return the results to the user.

Does anyone know the purpose of the calls where they add 50 to the operation code?

 

[mirtheil]

The 50 bias on a GET operation is the "GET KEY" bias. Here's the description from the SDK manual:
"The Get Key bias allows you to perform a Get operation without actually retrieving a data record. You can use Get Key to detect the presence of a value in a file. A Get Key operation is generally faster than its corresponding Get operation. You can use the Get Key operation with any of the following Get operations:..."

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Custom VB and Btrieve development.
Certified Pervasive Developer
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[larrym5353]

Thanks for the response. That explains what the are doing. I should probably use it in my C++ code also.