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"Monzer George Yazigi" <monzer_yazigi@hotmail.com> wrote
> I need to copy the content of
> TMemoryStream to an TBArray =  Array of Byte.
> I have the following code, and I am getting Stream Read Error.
 
>     MS:=TMemoryStream.Create;
>     imgView.IO.SaveToStreamJpeg(MS);
>     SZ:=MS.Size;
>     SetLength(img,SZ);
>     MS.ReadBuffer(img, SZ);

Monzer,

While I do not know the type of "img", 
I guess that you need something like
  If SZ > 0
    then MS.ReadBuffer(img[0], SZ);

HTH, JohnH

Hi John,
Sorry I missed writing it in my message. img is of type TBArray.

Regards

On Fri, 25 Jul 2008 11:24:44 -0500, "John Herbster"
<herb-sci1_AT_sbcglobal.net> wrote:

>
>"Monzer George Yazigi" <monzer_yazigi@hotmail.com> wrote
>> I need to copy the content of
>> TMemoryStream to an TBArray =  Array of Byte.
>> I have the following code, and I am getting Stream Read Error.
> 
>>     MS:=TMemoryStream.Create;
>>     imgView.IO.SaveToStreamJpeg(MS);
>>     SZ:=MS.Size;
>>     SetLength(img,SZ);
>>     MS.ReadBuffer(img, SZ);
>
>Monzer,
>
>While I do not know the type of "img", 
>I guess that you need something like
>  If SZ > 0
>    then MS.ReadBuffer(img[0], SZ);
>
>HTH, JohnH

Monzer George Yazigi wrote:

> Dear All,
> I need to copy the content of TMemoryStream to an TBArray =  Array of
> Byte.
> 
> I have the following code, and I am getting Stream Read Error.
> 
>      MS:=TMemoryStream.Create;
>      imgView.IO.SaveToStreamJpeg(MS);

After saving to a memory stream the position within the stream is at
the end of the stream, you'll need to set it back to from where you
want to start to read.

       MS.Position := 0;  // or use MS.Seek(0, soBeginning)

>      SZ:=MS.Size;
>      SetLength(img,SZ);
>      MS.ReadBuffer(img, SZ);

How is img defined? Is it a dynamic array of byte?
In that case you need to use img[0] instead.

       MS.ReadBuffer(img[0], SZ);

-- 
Pieter

Monzer George Yazigi wrote:

> Dear All,
> I need to copy the content of TMemoryStream to an TBArray =  Array of
> Byte.
> 
> I have the following code, and I am getting Stream Read Error.
> 
>      MS:=TMemoryStream.Create;
>      imgView.IO.SaveToStreamJpeg(MS);
>      SZ:=MS.Size;
>      SetLength(img,SZ);
>      MS.ReadBuffer(img, SZ);
> 
> Where imgView is a TImageEn component that has a JPG file loaded
> within it. 
> 
> Any advise?

a) you fail to set the MS.Position to 0 before you start reading from
it.
b) you need to pass img[0] to ReadBuffer to get the correct address
passed. Your current code would overwrite memory at the location of the
img variable.

-- 
Peter Below (TeamB)  
Don't be a vampire (http://slash7.com/pages/vampires), 
use the newsgroup archives :
http://www.tamaracka.com/search.htm
http://groups.google.com

Many thanks Pieter.

It worked.


On Fri, 25 Jul 2008 19:02:25 +0200, "Pieter Zijlstra"
<p.zylstra.notthis@hccnet.nl> wrote:

>Monzer George Yazigi wrote:
>
>> Dear All,
>> I need to copy the content of TMemoryStream to an TBArray =  Array of
>> Byte.
>> 
>> I have the following code, and I am getting Stream Read Error.
>> 
>>      MS:=TMemoryStream.Create;
>>      imgView.IO.SaveToStreamJpeg(MS);
>
>After saving to a memory stream the position within the stream is at
>the end of the stream, you'll need to set it back to from where you
>want to start to read.
>
>       MS.Position := 0;  // or use MS.Seek(0, soBeginning)
>
>>      SZ:=MS.Size;
>>      SetLength(img,SZ);
>>      MS.ReadBuffer(img, SZ);
>
>How is img defined? Is it a dynamic array of byte?
>In that case you need to use img[0] instead.
>
>       MS.ReadBuffer(img[0], SZ);

"Monzer George Yazigi" <monzer_yazigi@hotmail.com> wrote in message 
news:6vtj845qfu28o0f27q2lb4rjq76s1c6q34@4ax.com...

>     imgView.IO.SaveToStreamJpeg(MS);

You are not setting the stream's Position back to 0 before calling 
ReadBuffer():

    MS.Position := 0;

>     MS.ReadBuffer(img, SZ);

Because you are using a dynamic array, you have to index into its first 
element in order to pass the correct memory address to ReadBuffer():

    MS.ReadBuffer(img[0], SZ);


Gambit