store binary data in xml?

stan

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Dec 14, 2004, 3:45:03 AM12/14/04

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How to store binary data in xml?

Thanks.

Nils Haeck

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Dec 14, 2004, 4:14:26 AM12/14/04

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Hi Stan,

You can use BASE64 encoding for that.

Check out our XmlDocuments component, it supports automatic BASE64 encoding
through the TXmlNode.BinaryString property.
www.simdesign.nl/xml.html

Kind regards,

Nils Haeck
www.simdesign.nl

"stan" <st...@yahoo.com> wrote in message
news:41bea80f$1...@newsgroups.borland.com...

eshipman

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Dec 14, 2004, 9:26:51 AM12/14/04

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In article <41bea80f$1...@newsgroups.borland.com>, st...@yahoo.com says...

>
> How to store binary data in xml?
>

Base64 encode and enclose in a CDATA section.

This is a modified snippet of code from my XMLTable control
that converts a Dataset to XML, this is the code that handles
ftTypedBinary, ftBlob, and ftGraphic field types.

var
oXMLDoc: TdomDocument;
oRoot: TdomNode;
oChild: TdomElement;
oXMLdecl: TdomXmlDeclaration;
oXMLCDATASection: TdomCDATASection;
DecBlobStream: TMemoryStream;
EncBlobStream: TMemoryStream;
cDatasl: TStringList;
sFieldName: String;
sFieldValue: String;
begin
oXMLDoc := TdomDocument.Create;
try
oRoot := nil;
oChild := nil;
oNode := nil;
oAttr := nil;
oXMLdecl := nil;
oXMLCDATASection := nil;
oDTD := nil;
oRoot := TdomNode.Create(oXMLDoc);
oRoot := FXMLDoc.CreateElement('ROWSET');
oXMLDoc.AppendChild(oRoot);
oXMLdecl := oXMLDoc.CreateXmlDeclaration('1.0', 'UTF-8', 'yes');
oXMLDoc.InsertBefore(oXMLdecl, oXMLDoc.ChildNodes.Item(0));
oNode := oXMLDoc.CreateElement('ROW');
oXMLDoc.DocumentElement.AppendChild(oNode);
// Can't have spaces in Node Name so replace with underscore '_'
sFieldName := StringReplace(Source.FieldList.Fields[i].FieldName,
' ', '_', [rfReplaceAll]);
oChild := FXMLDoc.CreateElement(sFieldName);
oNode.AppendChild(oChild);
cDatasl := TStringList.Create;
DecBlobStream := TMemoryStream.Create;
EncBlobStream := TMemoryStream.Create;
try
TBlobField(Source.Fields[i]).SaveToStream(DecBlobStream);
DecBlobStream.Position := 0;
// base64 encoding source cut from Andreas
// Horstmeier's TCP/IP component suite
// email me at mr_delphi_developer at yahoo dot com
// if you want the converted source
cDatasl := encode_base64(DecBlobStream);
sFieldValue := cDatasl.Text;
oXMLCDATASection := TdomCDATASection.Create(oXMLDoc);
oXMLCDATASection.Data := sFieldValue;
oChild.AppendChild(oXMLCDATASection);
finally
FreeAndNil(EncBlobStream);
FreeAndNil(DecBlobStream);
FreeAndNil(cDatasl);
end;
finally
FreeAndNil(oXMLDoc);
end;
end;

Victor Hadianto

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Dec 19, 2004, 7:04:13 PM12/19/04

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>> How to store binary data in xml?
>>
>
> Base64 encode and enclose in a CDATA section.

Do you need to store it in CDATA section? Once it's Base64 encoded I think
you should be able to store it as an element.

eshipman

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Dec 20, 2004, 9:00:35 AM12/20/04

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In article <41c61682$1...@newsgroups.borland.com>, vic...@synop.com says...

If you really want to know, check the RFC. I think it
is a requirement.

danny heijl

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Dec 20, 2004, 2:22:17 PM12/20/04

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eshipman schreef:

> If you really want to know, check the RFC. I think it
> is a requirement.

base64Binary is a native XML data type (in XML schema).

Danny
---

eshipman

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Dec 20, 2004, 2:48:38 PM12/20/04

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In article <41c7266c$1...@newsgroups.borland.com>, danny heijl
<danny_dot_heijl_at_telenet_dot_be> says...

But he didn't specify that he would be using a schema and thus I gave
him an answer that he could use without using one or with using a DTD
only.