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From: Joe Cool on 31 Jul 2010 22:15
On Jul 31, 10:04 pm, Arne Vajhøj <a...(a)vajhoej.dk> wrote:
> On 31-07-2010 21:52, Joe Cool wrote:
>
>
>
>
>
> > On Jul 31, 9:46 pm, Arne Vajhøj<a...(a)vajhoej.dk>  wrote:
> >> On 31-07-2010 21:41, Joe Cool wrote:
>
> >>> On Jul 31, 9:21 pm, Arne Vajhøj<a...(a)vajhoej.dk>    wrote:
> >>>> On 31-07-2010 20:50, Joe Cool wrote:
> >>>>> On Jul 31, 8:41 pm, Arne Vajhøj<a...(a)vajhoej.dk>      wrote:
> >>>>>> On 31-07-2010 20:39, Joe Cool wrote:
> >>>>>>> On Jul 31, 8:37 pm, Arne Vajhøj<a...(a)vajhoej.dk>        wrote:
> >>>>>>>> On 31-07-2010 20:29, Joe Cool wrote:
>
> >>>>>>>>> On Jul 31, 8:02 pm, Arne Vajhøj<a...(a)vajhoej.dk>          wrote:
> >>>>>>>>>> On 31-07-2010 19:36, Joe Cool wrote:
>
> >>>>>>>>>>> I am cross posting this request for help in both the C#,NET and the
> >>>>>>>>>>> SQLServer newsgroups in he hope that some reader of one these
> >>>>>>>>>>> newsgroups can offer some help.
>
> >>>>>>>>>>> I am well aware that the image datatype (as well as others) are being
> >>>>>>>>>>> phased out in some future version of SQL Server. For that reason, in
> >>>>>>>>>>> all of my personal C#.NET projects that store images use the
> >>>>>>>>>>> varbinary(max) datatype.
>
> >>>>>>>>>>> I am in the process of converting a VB.NET project that I use for
> >>>>>>>>>>> consulting work with a former (and hopefully soon to be repeat)
> >>>>>>>>>>> employer tp C#.NET. When originally designed, their software was based
> >>>>>>>>>>> on SQL7. Currently their software supports SQL2005. One key table in
> >>>>>>>>>>> their database is a table of images and (not sure if it still does)
> >>>>>>>>>>> but legacy databases utilize the image datatype to store images. With
> >>>>>>>>>>> SQL7 I used a SQL command line utility called TEXTCOPY to extract the
> >>>>>>>>>>> binary content of image columns to a JPG file.
>
> >>>>>>>>>>> This utility needs to be able to extract these images to external
> >>>>>>>>>>> files even for legacy databases that may still use the image datatype.
> >>>>>>>>>>> But I find that the technique I use to extract images from a
> >>>>>>>>>>> varbinary(max) column doesn't work for image datatypes. And I see that
> >>>>>>>>>>> SQL2005, while it still supports image datatype, the TEXTCOPY utility
> >>>>>>>>>>> is nowhere to be found.
>
> >>>>>>>>>>> Any ideas on how to extract image data types from a SQL2005 database
> >>>>>>>>>>> with C#.NET?
>
> >>>>>>>>>> Have you tried the obvious: SqlConnection, SqlCommand, SELECT,
> >>>>>>>>>> ExecuteReader, SqlDataReader og læse kolonnen som byte[] ?
>
> >>>>>>>>> Here is what I am using that works with varbinary(max) datatype
> >>>>>>>>> columns.
>
> >>>>>>>>> SqlCommand cmd;
> >>>>>>>>> SqlDataReader rdr;
> >>>>>>>>> DataTable dataTable;
>
> >>>>>>>>> cmd = new SqlCommand("select imagecolumn, linkcolumn from images",
> >>>>>>>>> cn)'
> >>>>>>>>> rdr = cmd.ExecuteReader();
> >>>>>>>>> dataTable.Load(rdr);
>
> >>>>>>>> Drop the data table and try:
>
> >>>>>>>> while(rdr.Read())
> >>>>>>>> {
> >>>>>>>>          byte[] image = (byte[])rdr[0];
> >>>>>>>>          string link = (string)rdr[1];
> >>>>>>>>          // process image and link
>
> >>>>>>>> }
>
> >>>>>>> Umm, so are you saying that while the datatable works with a
> >>>>>>> varbinary(max) datatype, for an image datatype I should drop the
> >>>>>>> datatable and just use a data reader?
>
> >>>>>> I don't know if the data table is the problem.
>
> >>>>>> I know that the reader will work.
>
> >>>>>> And according to your description, then you don't need
> >>>>>> the data table.
>
> >>>>>> So it is worth a try.
>
> >>>>> The only reason I was trying to use a data table is because I am using
> >>>>> a support class library (that I also wrote) that returns data using
> >>>>> just a datatable. I suppose I can enhance it to also support returning
> >>>>> data with a data reader.
>
> >>>> What is the problem when you try getting the image with the
> >>>> current code?
>
> >>> The extracted files are smaller than the JPGs extracted by the VB.NET
> >>> version and are not valid JPG files (their content is not the same).
>
> >> Is the size in the DB correct?
>
> >> If yes - is the size in the data table correct?
>
> > In the FileStream object's Write mthod, I am using
> > ((byte[])dataTable.Rows[i][0]).Length as the number of bytes to write.
>
> > I assume thelength is the DB is correct since I am using the same DB
> > to test the C#.NET program to test with that I originally used the
> > VB.NET programs to originally extract the JPs with.
>
> How does the VB.NET and C# code differ?

I already posted the C#.NET code. The VB.NET code (as my original post
mentioned) used the now (apparent) non-existant TEXTCOPY command line
utility.
From: Arne Vajhøj on 31 Jul 2010 22:22
On 31-07-2010 22:15, Joe Cool wrote:
> On Jul 31, 10:04 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>> On 31-07-2010 21:52, Joe Cool wrote:
>>> On Jul 31, 9:46 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>> On 31-07-2010 21:41, Joe Cool wrote:
>>
>>>>> On Jul 31, 9:21 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>> On 31-07-2010 20:50, Joe Cool wrote:
>>>>>>> On Jul 31, 8:41 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>>>> On 31-07-2010 20:39, Joe Cool wrote:
>>>>>>>>> On Jul 31, 8:37 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>>>>>> On 31-07-2010 20:29, Joe Cool wrote:
>>
>>>>>>>>>>> On Jul 31, 8:02 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>>>>>>>> On 31-07-2010 19:36, Joe Cool wrote:
>>
>>>>>>>>>>>>> I am cross posting this request for help in both the C#,NET and the
>>>>>>>>>>>>> SQLServer newsgroups in he hope that some reader of one these
>>>>>>>>>>>>> newsgroups can offer some help.
>>
>>>>>>>>>>>>> I am well aware that the image datatype (as well as others) are being
>>>>>>>>>>>>> phased out in some future version of SQL Server. For that reason, in
>>>>>>>>>>>>> all of my personal C#.NET projects that store images use the
>>>>>>>>>>>>> varbinary(max) datatype.
>>
>>>>>>>>>>>>> I am in the process of converting a VB.NET project that I use for
>>>>>>>>>>>>> consulting work with a former (and hopefully soon to be repeat)
>>>>>>>>>>>>> employer tp C#.NET. When originally designed, their software was based
>>>>>>>>>>>>> on SQL7. Currently their software supports SQL2005. One key table in
>>>>>>>>>>>>> their database is a table of images and (not sure if it still does)
>>>>>>>>>>>>> but legacy databases utilize the image datatype to store images. With
>>>>>>>>>>>>> SQL7 I used a SQL command line utility called TEXTCOPY to extract the
>>>>>>>>>>>>> binary content of image columns to a JPG file.
>>
>>>>>>>>>>>>> This utility needs to be able to extract these images to external
>>>>>>>>>>>>> files even for legacy databases that may still use the image datatype.
>>>>>>>>>>>>> But I find that the technique I use to extract images from a
>>>>>>>>>>>>> varbinary(max) column doesn't work for image datatypes. And I see that
>>>>>>>>>>>>> SQL2005, while it still supports image datatype, the TEXTCOPY utility
>>>>>>>>>>>>> is nowhere to be found.
>>
>>>>>>>>>>>>> Any ideas on how to extract image data types from a SQL2005 database
>>>>>>>>>>>>> with C#.NET?
>>
>>>>>>>>>>>> Have you tried the obvious: SqlConnection, SqlCommand, SELECT,
>>>>>>>>>>>> ExecuteReader, SqlDataReader og l�se kolonnen som byte[] ?
>>
>>>>>>>>>>> Here is what I am using that works with varbinary(max) datatype
>>>>>>>>>>> columns.
>>
>>>>>>>>>>> SqlCommand cmd;
>>>>>>>>>>> SqlDataReader rdr;
>>>>>>>>>>> DataTable dataTable;
>>
>>>>>>>>>>> cmd = new SqlCommand("select imagecolumn, linkcolumn from images",
>>>>>>>>>>> cn)'
>>>>>>>>>>> rdr = cmd.ExecuteReader();
>>>>>>>>>>> dataTable.Load(rdr);
>>
>>>>>>>>>> Drop the data table and try:
>>
>>>>>>>>>> while(rdr.Read())
>>>>>>>>>> {
>>>>>>>>>> byte[] image = (byte[])rdr[0];
>>>>>>>>>> string link = (string)rdr[1];
>>>>>>>>>> // process image and link
>>
>>>>>>>>>> }
>>
>>>>>>>>> Umm, so are you saying that while the datatable works with a
>>>>>>>>> varbinary(max) datatype, for an image datatype I should drop the
>>>>>>>>> datatable and just use a data reader?
>>
>>>>>>>> I don't know if the data table is the problem.
>>
>>>>>>>> I know that the reader will work.
>>
>>>>>>>> And according to your description, then you don't need
>>>>>>>> the data table.
>>
>>>>>>>> So it is worth a try.
>>
>>>>>>> The only reason I was trying to use a data table is because I am using
>>>>>>> a support class library (that I also wrote) that returns data using
>>>>>>> just a datatable. I suppose I can enhance it to also support returning
>>>>>>> data with a data reader.
>>
>>>>>> What is the problem when you try getting the image with the
>>>>>> current code?
>>
>>>>> The extracted files are smaller than the JPGs extracted by the VB.NET
>>>>> version and are not valid JPG files (their content is not the same).
>>
>>>> Is the size in the DB correct?
>>
>>>> If yes - is the size in the data table correct?
>>
>>> In the FileStream object's Write mthod, I am using
>>> ((byte[])dataTable.Rows[i][0]).Length as the number of bytes to write.
>>
>>> I assume thelength is the DB is correct since I am using the same DB
>>> to test the C#.NET program to test with that I originally used the
>>> VB.NET programs to originally extract the JPs with.
>>
>> How does the VB.NET and C# code differ?
>
> I already posted the C#.NET code. The VB.NET code (as my original post
> mentioned) used the now (apparent) non-existant TEXTCOPY command line
> utility.

Can you create a complete example that illustrates the problem.

Basically it should work.

Here is a copy of some old code of mine:

SqlCommand ins = new SqlCommand("INSERT INTO imgtest
VALUES(@id,@img)", con);
ins.Parameters.Add("@id", SqlDbType.Int);
ins.Parameters.Add("@img", SqlDbType.Image);
ins.Parameters["@id"].Value = 1;
ins.Parameters["@img"].Value = imgdata;
ins.ExecuteNonQuery();
....
SqlCommand sel = new SqlCommand("SELECT img FROM imgtest WHERE
id = @id", con);
sel.Parameters.Add("@id", SqlDbType.Int);
sel.Parameters["@id"].Value = 1;
byte[] imgdata2 = (byte[])sel.ExecuteScalar();

Arne

From: Joe Cool on 31 Jul 2010 22:31
On Jul 31, 10:22 pm, Arne Vajhøj <a...(a)vajhoej.dk> wrote:
> On 31-07-2010 22:15, Joe Cool wrote:
>
>
>
>
>
> > On Jul 31, 10:04 pm, Arne Vajhøj<a...(a)vajhoej.dk>  wrote:
> >> On 31-07-2010 21:52, Joe Cool wrote:
> >>> On Jul 31, 9:46 pm, Arne Vajhøj<a...(a)vajhoej.dk>    wrote:
> >>>> On 31-07-2010 21:41, Joe Cool wrote:
>
> >>>>> On Jul 31, 9:21 pm, Arne Vajhøj<a...(a)vajhoej.dk>      wrote:
> >>>>>> On 31-07-2010 20:50, Joe Cool wrote:
> >>>>>>> On Jul 31, 8:41 pm, Arne Vajhøj<a...(a)vajhoej.dk>        wrote:
> >>>>>>>> On 31-07-2010 20:39, Joe Cool wrote:
> >>>>>>>>> On Jul 31, 8:37 pm, Arne Vajhøj<a...(a)vajhoej.dk>          wrote:
> >>>>>>>>>> On 31-07-2010 20:29, Joe Cool wrote:
>
> >>>>>>>>>>> On Jul 31, 8:02 pm, Arne Vajhøj<a...(a)vajhoej.dk>            wrote:
> >>>>>>>>>>>> On 31-07-2010 19:36, Joe Cool wrote:
>
> >>>>>>>>>>>>> I am cross posting this request for help in both the C#,NET and the
> >>>>>>>>>>>>> SQLServer newsgroups in he hope that some reader of one these
> >>>>>>>>>>>>> newsgroups can offer some help.
>
> >>>>>>>>>>>>> I am well aware that the image datatype (as well as others) are being
> >>>>>>>>>>>>> phased out in some future version of SQL Server. For that reason, in
> >>>>>>>>>>>>> all of my personal C#.NET projects that store images use the
> >>>>>>>>>>>>> varbinary(max) datatype.
>
> >>>>>>>>>>>>> I am in the process of converting a VB.NET project that I use for
> >>>>>>>>>>>>> consulting work with a former (and hopefully soon to be repeat)
> >>>>>>>>>>>>> employer tp C#.NET. When originally designed, their software was based
> >>>>>>>>>>>>> on SQL7. Currently their software supports SQL2005. One key table in
> >>>>>>>>>>>>> their database is a table of images and (not sure if it still does)
> >>>>>>>>>>>>> but legacy databases utilize the image datatype to store images. With
> >>>>>>>>>>>>> SQL7 I used a SQL command line utility called TEXTCOPY to extract the
> >>>>>>>>>>>>> binary content of image columns to a JPG file.
>
> >>>>>>>>>>>>> This utility needs to be able to extract these images to external
> >>>>>>>>>>>>> files even for legacy databases that may still use the image datatype.
> >>>>>>>>>>>>> But I find that the technique I use to extract images from a
> >>>>>>>>>>>>> varbinary(max) column doesn't work for image datatypes. And I see that
> >>>>>>>>>>>>> SQL2005, while it still supports image datatype, the TEXTCOPY utility
> >>>>>>>>>>>>> is nowhere to be found.
>
> >>>>>>>>>>>>> Any ideas on how to extract image data types from a SQL2005 database
> >>>>>>>>>>>>> with C#.NET?
>
> >>>>>>>>>>>> Have you tried the obvious: SqlConnection, SqlCommand, SELECT,
> >>>>>>>>>>>> ExecuteReader, SqlDataReader og læse kolonnen som byte[] ?
>
> >>>>>>>>>>> Here is what I am using that works with varbinary(max) datatype
> >>>>>>>>>>> columns.
>
> >>>>>>>>>>> SqlCommand cmd;
> >>>>>>>>>>> SqlDataReader rdr;
> >>>>>>>>>>> DataTable dataTable;
>
> >>>>>>>>>>> cmd = new SqlCommand("select imagecolumn, linkcolumn from images",
> >>>>>>>>>>> cn)'
> >>>>>>>>>>> rdr = cmd.ExecuteReader();
> >>>>>>>>>>> dataTable.Load(rdr);
>
> >>>>>>>>>> Drop the data table and try:
>
> >>>>>>>>>> while(rdr.Read())
> >>>>>>>>>> {
> >>>>>>>>>>           byte[] image = (byte[])rdr[0];
> >>>>>>>>>>           string link = (string)rdr[1];
> >>>>>>>>>>           // process image and link
>
> >>>>>>>>>> }
>
> >>>>>>>>> Umm, so are you saying that while the datatable works with a
> >>>>>>>>> varbinary(max) datatype, for an image datatype I should drop the
> >>>>>>>>> datatable and just use a data reader?
>
> >>>>>>>> I don't know if the data table is the problem.
>
> >>>>>>>> I know that the reader will work.
>
> >>>>>>>> And according to your description, then you don't need
> >>>>>>>> the data table.
>
> >>>>>>>> So it is worth a try.
>
> >>>>>>> The only reason I was trying to use a data table is because I am using
> >>>>>>> a support class library (that I also wrote) that returns data using
> >>>>>>> just a datatable. I suppose I can enhance it to also support returning
> >>>>>>> data with a data reader.
>
> >>>>>> What is the problem when you try getting the image with the
> >>>>>> current code?
>
> >>>>> The extracted files are smaller than the JPGs extracted by the VB.NET
> >>>>> version and are not valid JPG files (their content is not the same)..
>
> >>>> Is the size in the DB correct?
>
> >>>> If yes - is the size in the data table correct?
>
> >>> In the FileStream object's Write mthod, I am using
> >>> ((byte[])dataTable.Rows[i][0]).Length as the number of bytes to write..
>
> >>> I assume thelength is the DB is correct since I am using the same DB
> >>> to test the C#.NET program to test with that I originally used the
> >>> VB.NET programs to originally extract the JPs with.
>
> >> How does the VB.NET and C# code differ?
>
> > I already posted the C#.NET code. The VB.NET code (as my original post
> > mentioned) used the now (apparent) non-existant TEXTCOPY command line
> > utility.
>
> Can you create a complete example that illustrates the problem.
>
> Basically it should work.
>
> Here is a copy of some old code of mine:
>
>          SqlCommand ins = new SqlCommand("INSERT INTO imgtest
> VALUES(@id,@img)", con);
>          ins.Parameters.Add("@id", SqlDbType.Int);
>          ins.Parameters.Add("@img", SqlDbType.Image);
>          ins.Parameters["@id"].Value = 1;
>          ins.Parameters["@img"].Value = imgdata;
>          ins.ExecuteNonQuery();
> ...
>          SqlCommand sel = new SqlCommand("SELECT img FROM imgtest WHERE
> id = @id", con);
>          sel.Parameters.Add("@id", SqlDbType.Int);
>          sel.Parameters["@id"].Value = 1;
>          byte[] imgdata2 = (byte[])sel.ExecuteScalar();

At present I do not have access to the code that originally loads the
image data, but I assume it is similar to yours.

When I first developed my personal apps that stored images in the
database I used the image datatype and used the ExecuteScaler method
to retrieve them. When I switched to my support class library I
switched to the datatable method I have already described. So we are
at full circle, when I first tried the datatable method to retrieve an
Image datatye type column and had problems.
From: Erland Sommarskog on 1 Aug 2010 05:09
Joe Cool (joecool1969(a)live.com) writes:
> I am in the process of converting a VB.NET project that I use for
> consulting work with a former (and hopefully soon to be repeat)
> employer tp C#.NET. When originally designed, their software was based
> on SQL7. Currently their software supports SQL2005. One key table in
> their database is a table of images and (not sure if it still does)
> but legacy databases utilize the image datatype to store images. With
> SQL7 I used a SQL command line utility called TEXTCOPY to extract the
> binary content of image columns to a JPG file.

Do you need to connect to the legacy databases?

On which version of SQL Server do they run on?

Note that it is only if you need to connect to them, and if they run on
older versions of SQL Server you need to bother. If they run on SQL 2005,
you can say convert(varbinary(MAX), imgcol) and your done.

--
Erland Sommarskog, SQL Server MVP, esquel(a)sommarskog.se

Links for SQL Server Books Online:
SQL 2008: http://msdn.microsoft.com/en-us/sqlserver/cc514207.aspx
SQL 2005: http://msdn.microsoft.com/en-us/sqlserver/bb895970.aspx
SQL 2000: http://www.microsoft.com/sql/prodinfo/previousversions/books.mspx

From: Arne Vajhøj on 1 Aug 2010 15:23
On 31-07-2010 22:31, Joe Cool wrote:
> On Jul 31, 10:22 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>> On 31-07-2010 22:15, Joe Cool wrote:
>>> On Jul 31, 10:04 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>> On 31-07-2010 21:52, Joe Cool wrote:
>>>>> On Jul 31, 9:46 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>> On 31-07-2010 21:41, Joe Cool wrote:
>>
>>>>>>> On Jul 31, 9:21 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>>>> On 31-07-2010 20:50, Joe Cool wrote:
>>>>>>>>> On Jul 31, 8:41 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>>>>>> On 31-07-2010 20:39, Joe Cool wrote:
>>>>>>>>>>> On Jul 31, 8:37 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>>>>>>>> On 31-07-2010 20:29, Joe Cool wrote:
>>
>>>>>>>>>>>>> On Jul 31, 8:02 pm, Arne Vajh�j<a...(a)vajhoej.dk> wrote:
>>>>>>>>>>>>>> On 31-07-2010 19:36, Joe Cool wrote:
>>
>>>>>>>>>>>>>>> I am cross posting this request for help in both the C#,NET and the
>>>>>>>>>>>>>>> SQLServer newsgroups in he hope that some reader of one these
>>>>>>>>>>>>>>> newsgroups can offer some help.
>>
>>>>>>>>>>>>>>> I am well aware that the image datatype (as well as others) are being
>>>>>>>>>>>>>>> phased out in some future version of SQL Server. For that reason, in
>>>>>>>>>>>>>>> all of my personal C#.NET projects that store images use the
>>>>>>>>>>>>>>> varbinary(max) datatype.
>>
>>>>>>>>>>>>>>> I am in the process of converting a VB.NET project that I use for
>>>>>>>>>>>>>>> consulting work with a former (and hopefully soon to be repeat)
>>>>>>>>>>>>>>> employer tp C#.NET. When originally designed, their software was based
>>>>>>>>>>>>>>> on SQL7. Currently their software supports SQL2005. One key table in
>>>>>>>>>>>>>>> their database is a table of images and (not sure if it still does)
>>>>>>>>>>>>>>> but legacy databases utilize the image datatype to store images. With
>>>>>>>>>>>>>>> SQL7 I used a SQL command line utility called TEXTCOPY to extract the
>>>>>>>>>>>>>>> binary content of image columns to a JPG file.
>>
>>>>>>>>>>>>>>> This utility needs to be able to extract these images to external
>>>>>>>>>>>>>>> files even for legacy databases that may still use the image datatype.
>>>>>>>>>>>>>>> But I find that the technique I use to extract images from a
>>>>>>>>>>>>>>> varbinary(max) column doesn't work for image datatypes. And I see that
>>>>>>>>>>>>>>> SQL2005, while it still supports image datatype, the TEXTCOPY utility
>>>>>>>>>>>>>>> is nowhere to be found.
>>
>>>>>>>>>>>>>>> Any ideas on how to extract image data types from a SQL2005 database
>>>>>>>>>>>>>>> with C#.NET?
>>
>>>>>>>>>>>>>> Have you tried the obvious: SqlConnection, SqlCommand, SELECT,
>>>>>>>>>>>>>> ExecuteReader, SqlDataReader og l�se kolonnen som byte[] ?
>>
>>>>>>>>>>>>> Here is what I am using that works with varbinary(max) datatype
>>>>>>>>>>>>> columns.
>>
>>>>>>>>>>>>> SqlCommand cmd;
>>>>>>>>>>>>> SqlDataReader rdr;
>>>>>>>>>>>>> DataTable dataTable;
>>
>>>>>>>>>>>>> cmd = new SqlCommand("select imagecolumn, linkcolumn from images",
>>>>>>>>>>>>> cn)'
>>>>>>>>>>>>> rdr = cmd.ExecuteReader();
>>>>>>>>>>>>> dataTable.Load(rdr);
>>
>>>>>>>>>>>> Drop the data table and try:
>>
>>>>>>>>>>>> while(rdr.Read())
>>>>>>>>>>>> {
>>>>>>>>>>>> byte[] image = (byte[])rdr[0];
>>>>>>>>>>>> string link = (string)rdr[1];
>>>>>>>>>>>> // process image and link
>>
>>>>>>>>>>>> }
>>
>>>>>>>>>>> Umm, so are you saying that while the datatable works with a
>>>>>>>>>>> varbinary(max) datatype, for an image datatype I should drop the
>>>>>>>>>>> datatable and just use a data reader?
>>
>>>>>>>>>> I don't know if the data table is the problem.
>>
>>>>>>>>>> I know that the reader will work.
>>
>>>>>>>>>> And according to your description, then you don't need
>>>>>>>>>> the data table.
>>
>>>>>>>>>> So it is worth a try.
>>
>>>>>>>>> The only reason I was trying to use a data table is because I am using
>>>>>>>>> a support class library (that I also wrote) that returns data using
>>>>>>>>> just a datatable. I suppose I can enhance it to also support returning
>>>>>>>>> data with a data reader.
>>
>>>>>>>> What is the problem when you try getting the image with the
>>>>>>>> current code?
>>
>>>>>>> The extracted files are smaller than the JPGs extracted by the VB.NET
>>>>>>> version and are not valid JPG files (their content is not the same).
>>
>>>>>> Is the size in the DB correct?
>>
>>>>>> If yes - is the size in the data table correct?
>>
>>>>> In the FileStream object's Write mthod, I am using
>>>>> ((byte[])dataTable.Rows[i][0]).Length as the number of bytes to write.
>>
>>>>> I assume thelength is the DB is correct since I am using the same DB
>>>>> to test the C#.NET program to test with that I originally used the
>>>>> VB.NET programs to originally extract the JPs with.
>>
>>>> How does the VB.NET and C# code differ?
>>
>>> I already posted the C#.NET code. The VB.NET code (as my original post
>>> mentioned) used the now (apparent) non-existant TEXTCOPY command line
>>> utility.
>>
>> Can you create a complete example that illustrates the problem.
>>
>> Basically it should work.
>>
>> Here is a copy of some old code of mine:
>>
>> SqlCommand ins = new SqlCommand("INSERT INTO imgtest
>> VALUES(@id,@img)", con);
>> ins.Parameters.Add("@id", SqlDbType.Int);
>> ins.Parameters.Add("@img", SqlDbType.Image);
>> ins.Parameters["@id"].Value = 1;
>> ins.Parameters["@img"].Value = imgdata;
>> ins.ExecuteNonQuery();
>> ...
>> SqlCommand sel = new SqlCommand("SELECT img FROM imgtest WHERE
>> id = @id", con);
>> sel.Parameters.Add("@id", SqlDbType.Int);
>> sel.Parameters["@id"].Value = 1;
>> byte[] imgdata2 = (byte[])sel.ExecuteScalar();
>
> At present I do not have access to the code that originally loads the
> image data, but I assume it is similar to yours.
>
> When I first developed my personal apps that stored images in the
> database I used the image datatype and used the ExecuteScaler method
> to retrieve them. When I switched to my support class library I
> switched to the datatable method I have already described. So we are
> at full circle, when I first tried the datatable method to retrieve an
> Image datatye type column and had problems.

I don't think we will get any further until you start working
with the code and try post some code that demonstrates the
problem.

Arne
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