DOM Parse XML source

version 2004 (Modified)

DOM Parse XML source (document{; validation{; dtd}}) String

The DOM Parse XML source command parses a document containing an XML structure and returns a reference for this document. The command can validate (or not) the document.

The document can be located on the disk or on the Internet/Intranet.

In the document parameter, you can pass:

• either a standard complete pathname (of the type C:\\Folder\\File\\... under Windows and MacintoshHD:Folder:File under Mac OS),

• or a Unix path under Mac OS (which must start with /).

• or a network path of the type http://www.site.com/File or ftp://public.ftp.com...

The Boolean parameter validation is used to indicate whether or not to validate the structure using the DTD.

• If validation equals True, the structure will be validated. In this case, the parser will attempt to validate the XML structure of the document based either on the DTD defined or referred to in the document, or that designated by the dtd parameter.

• If validation equals False, the structure will not be validated.

The third parameter, dtd, is used to indicate the specific DTD for document parsing. If you use this parameter, the command will not take the DTD referred to in the XML document into account.

There are two ways to specify a DTD:

• as a reference. To do this, pass the complete pathname of the new DTD in the dtd parameter. If the document indicated does not contain a valid DTD, the dtd parameter is ignored and an error is generated.

• directly in a text. In this case, if the contents of the parameter begin with "<?xml", 4D will consider that it is the DTD; otherwise, 4D will consider it as a pathname.

If validation cannot be performed (no DTD, incorrect URL to DTD, etc.), an error is generated. The Error system variable indicates the error number. You can intercept this error using a method installed by the ON ERR CALL command.

The command returns a 16-character string (ElementRef) making up the reference in the memory of the document virtual structure. This reference should be used with other XML parsing commands.

Important: Once you no longer have any need for it, remember to call the DOM CLOSE XML command with this reference in order to free up the memory.

1. Opening an XML document located on disk, without validation:

   $xml_Struct_Ref:=DOM Parse XML source("C:\\import.xml")

2. Opening an XML document located next to the database structure file, without validation:

   $xml_Struct_Ref:=DOM Parse XML source("import.xml")

3. Opening an XML document located on disk and validation using a DTD on the disk:

   $xml_Struct_Ref:=DOM Parse XML source("C:\\import.xml";True;"C:\\import_dtd.xml")

4. Opening an XML document located at a specific URL, without validation:

   $xml_Struct_Ref:=DOM Parse XML source("http://www.4D.com/xml/import.xml")

DOM CLOSE XML, DOM Parse XML variable.

If the command has been correctly executed, the system variable OK is set to 1. Otherwise, it is set to 0.