Extracting binary file from sql database image field to disk

[=?Utf-8?B?U2NvdHQ=?=]

I am trying to extract a zip file in a database image field to disk. For some
reason, the zip file is getting corrupted / truncated. I have code in ASP
which extracts the zip file no problem, so i know it is not corrupted in the
table. Any help would be appreciated.

FileStream fs = new FileStream(sFil ePath + "TestFile.z ip",
FileMode.Create New);
BinaryWriter bw = new BinaryWriter(fs );
byte[] buffer =
Encoding.ASCII. GetBytes(DataRe ader[sField].ToString());
bw.Write(buffer );
bw.Close();
fs.Close();

[Jon Skeet [C# MVP]]

Re: Extracting binary file from sql database image field to disk

Scott <Scott@discussi ons.microsoft.c omwrote:

I am trying to extract a zip file in a database image field to disk. For some
reason, the zip file is getting corrupted / truncated. I have code in ASP
which extracts the zip file no problem, so i know it is not corrupted in the
table. Any help would be appreciated.
>
FileStream fs = new FileStream(sFil ePath + "TestFile.z ip",
FileMode.Create New);
BinaryWriter bw = new BinaryWriter(fs );
byte[] buffer =
Encoding.ASCII. GetBytes(DataRe ader[sField].ToString());
bw.Write(buffer );
bw.Close();
fs.Close();

Don't convert the binary data to a string - that's a recipe for a
disaster.

If you look at DataReader[sField].GetType(), what does it say?

--
Jon Skeet - <skeet@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too

[Matt F]

Re: Extracting binary file from sql database image field to disk

I use the binaryformatter class for this type of thing --- MSDN example for
the binaryformatter class has a pretty good example.

Take a look at:
http://msdn2.microsoft.com/en-us/lib...formatter.aspx

[Jon Skeet [C# MVP]]

Re: Extracting binary file from sql database image field to disk

Matt F <mfielderREMOVE CAPS@nospam.nos pamwrote:

I use the binaryformatter class for this type of thing --- MSDN example for
the binaryformatter class has a pretty good example.

It's a zip file - natural binary data to start with. Serializing it
would add an extra layer for no good reason, *and* make it
hard/impossible to use from other platforms.

--
Jon Skeet - <skeet@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too

[=?Utf-8?B?U2NvdHQ=?=]

Re: Extracting binary file from sql database image field to disk



"Jon Skeet [C# MVP]" wrote:

Scott <Scott@discussi ons.microsoft.c omwrote:

I am trying to extract a zip file in a database image field to disk. For some
reason, the zip file is getting corrupted / truncated. I have code in ASP
which extracts the zip file no problem, so i know it is not corrupted in the
table. Any help would be appreciated.

FileStream fs = new FileStream(sFil ePath + "TestFile.z ip",
FileMode.Create New);
BinaryWriter bw = new BinaryWriter(fs );
byte[] buffer =
Encoding.ASCII. GetBytes(DataRe ader[sField].ToString());
bw.Write(buffer );
bw.Close();
fs.Close();

>
Don't convert the binary data to a string - that's a recipe for a
disaster.
>
If you look at DataReader[sField].GetType(), what does it say?
>
--
Jon Skeet - <skeet@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too
>

The DataReader[sField].GetType() comes back as System.String

[Jon Skeet [C# MVP]]

Re: Extracting binary file from sql database image field to disk

Scott <Scott@discussi ons.microsoft.c omwrote:

If you look at DataReader[sField].GetType(), what does it say?

The DataReader[sField].GetType() comes back as System.String

Okay, that's a bad start. What's the data type in the database, and how
have you stored the zip file in there in the first place? Storing a
binary block of data (such as a zip file) in a text field is a really
bad move...

--
Jon Skeet - <skeet@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too