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POConversion from VB6 string data to .NET byte array
 

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  1. POConversion from VB6 string data to .NET byte array
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    <p>I'm writing a C# application that reads data from an SQL database generated by VB6 code. The data is an array of Singles. I'm trying to convert them to a float[]</p> <p>Below is the VB6 code that wrote the data in the database (cannot change this code):</p> <pre><code> Set fso = New FileSystemObject strFilePath = "c:\temp\temp.tmp" ' Output the data to a temporary file intFileNr = FreeFile Open strFilePath For Binary Access Write As #intFileNr Put #intFileNr, , GetSize(Data, 1) Put #intFileNr, , GetSize(Data, 2) Put #intFileNr, , Data Close #intFileNr ' Read the data back AS STRING Open strFilePath For Binary Access Read As #intFileNr strData = String$(LOF(intFileNr), 32) Get #intFileNr, 1, strData Close #intFileNr Call Field.AppendChunk(strData) </code></pre> <p>As you can see, the data is put in a temporary file, then read back as VB6 String and wrote in the database (row of type dbLongBinary)</p> <p>I've tried the following:</p> <p>Doing a BlockCopy</p> <pre><code>byte[] source = databaseValue as byte[]; float [,] destination = new float[BitConverter.ToInt32(source, 0), BitConverter.ToInt32(source, 4)]; Buffer.BlockCopy(source, 8, destination, 0, 50 * 99 * 4); </code></pre> <p>The problem here is the VB6 binary to string conversion. The VB6 string char is 2 bytes wide and I don't know how to transform this back to a binary format I can handle.</p> <p>Below is a dump of the temp file that the VB6 code generates: <a href="http://robbertdam.nl/share/dump%20of%20text%20file%20generated%20by%20VB6.png" rel="nofollow noreferrer">alt text http://robbertdam.nl/share/dump%20of%20text%20file%20generated%20by%20VB6.png</a></p> <p>And here is the dump of the data as I read it from the database in (=the VB6 string): <a href="http://robbertdam.nl/share/dump%20of%20database%20field.png" rel="nofollow noreferrer">alt text http://robbertdam.nl/share/dump%20of%20database%20field.png</a></p>
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    1. USRobbert Dam
    1. USRobbert Dam
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      1. POConversion from VB6 string data to .NET byte array
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      1. VTUpMod
    1. COAre you sure you got the right binary dumps here? I can see the unicode padding introduced by LINQ for some seqence but they are not matching up exactly.
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      1. POConversion from VB6 string data to .NET byte array
      1. USRS Conley
    2. COHowever both are the same size arrays a (0 to 2, 0 to 12) so I think if copy this into another byte array and skip every other byte you should be good with the rest of the code I posted.
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      1. POConversion from VB6 string data to .NET byte array
      1. USRS Conley
    3. COSo the C# code has to handle how many bits per byte and bytes per float?
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      1. POConversion from VB6 string data to .NET byte array
      1. USstevehipwell
 

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