ReadBinHex method

[Karine Bosch]

Hi,

I'm trying to read binary information from an XMLTextReader and to save
it to a .jpg file, using a FileStream. I don't want to use an
XmlDocument because of performance reasons. But the only example code I
could find is:

byte[] binhex = new byte[1000];
do {
binhexlen = reader.ReadBinHex(binhex, 0, 50);
for (int i=0; i < binhexlen; i++) Console.Write(binhex[i]);
} while (reader.Name == "BinHex");

Is there any way to discover the length of the binary data on
beforehand? Or can someone give me a hint on how to complete my code
hereunder?

oPreviewStream = new FileStream(@"c:\temp\temp.jpg",
FileMode.Create, FileAccess.Write);
if (oPreviewStream != null)
{
// oTextReader.Value.Length returns zero in this case, I
suppose because of the binary content.
byte[] byteStream = new byte[oTextReader.Value.Length];
oTextReader.ReadBinHex(byteStream, 0,
oTextReader.Value.Length - 1);
oPreviewStream.Write(byteStream, 0, byteStream.Length);
oPreviewStream.Flush();
oPreviewStream.Close();
}
(This code snippet is not complete and not working).

Thanks in advance for the help. Kind regards,

Karine Bosch

[Martin Honnen]

Karine Bosch wrote:

I'm trying to read binary information from an XMLTextReader and to save
it to a .jpg file, using a FileStream.
Is there any way to discover the length of the binary data on
beforehand? Or can someone give me a hint on how to complete my code
hereunder?

oPreviewStream = new FileStream(@"c:\temp\temp.jpg",
FileMode.Create, FileAccess.Write);
if (oPreviewStream != null)
{
// oTextReader.Value.Length returns zero in this case, I
suppose because of the binary content.
byte[] byteStream = new byte[oTextReader.Value.Length];
oTextReader.ReadBinHex(byteStream, 0,
oTextReader.Value.Length - 1);
oPreviewStream.Write(byteStream, 0, byteStream.Length);
oPreviewStream.Flush();
oPreviewStream.Close();

Read the bytes into a buffer array and write that to the file stream as
long as needed e.g. pseudo code

byte[] buffer = new byte[1024];
Stream fileStream = new FileStream(@"whatever.jpg",
FileMode.Create, FileAccess.Write);

while (xmlReader.Name == hexElementName && xmlReader.NodeType !=
XmlNodeType.EndElement) {
int length = xmlReader.ReadBinHex(buffer, 0, buffer.Length);
if (length != 0) {
fileStream.Write(buffer, 0, length);
}
}
fileStream.Close();
--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/

[Karine Bosch]

Thanks, this works!
Kind regards,
Karine Bosch

Martin Honnen schreef:

Karine Bosch wrote:

I'm trying to read binary information from an XMLTextReader and to save
it to a .jpg file, using a FileStream.
Is there any way to discover the length of the binary data on
beforehand? Or can someone give me a hint on how to complete my code
hereunder?

oPreviewStream = new FileStream(@"c:\temp\temp.jpg",
FileMode.Create, FileAccess.Write);
if (oPreviewStream != null)
{
// oTextReader.Value.Length returns zero in this case, I
suppose because of the binary content.
byte[] byteStream = new byte[oTextReader.Value.Length];
oTextReader.ReadBinHex(byteStream, 0,
oTextReader.Value.Length - 1);
oPreviewStream.Write(byteStream, 0, byteStream.Length);
oPreviewStream.Flush();
oPreviewStream.Close();

Read the bytes into a buffer array and write that to the file stream as
long as needed e.g. pseudo code

byte[] buffer = new byte[1024];
Stream fileStream = new FileStream(@"whatever.jpg",
FileMode.Create, FileAccess.Write);

while (xmlReader.Name == hexElementName && xmlReader.NodeType !=
XmlNodeType.EndElement) {
int length = xmlReader.ReadBinHex(buffer, 0, buffer.Length);
if (length != 0) {
fileStream.Write(buffer, 0, length);
}
}
fileStream.Close();
--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/