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4D v14.3

DOM Get XML document ref


DOM Get XML document ref ( elementRef ) -> Function result

Parameter	Type	Description
elementRef	Text	Reference of existing element in DOM tree
Function result	Text	Reference of first element of a DOM tree (document node)

Description

The DOM Get XML document ref command is used to recover the reference of the "document" element of the DOM tree whose reference you have passed in elementRef. The document element is the first element of a DOM tree; it is the parent of the root element.

The reference of the document element lets you handle the "Doctype" and "Processing Instruction" nodes. It can only be used with the DOM Append XML child node and DOM GET XML CHILD NODES commands.

At this level, you can only append processing instructions and comments or replace the Doctype node. You cannot create CDATA or Text nodes there.

Example

In this example, we want to find the DTD declaration of the XML document:

 C_TEXT($rootRef)

 $rootRef:=DOM Parse XML source("")

 If(OK=1)

    C_TEXT($documentRef)

  // we are looking for the document node, since it is the node to which

  // the DOCTYPE node is attached before the root node

    $documentRef:=DOM Get XML document ref($rootRef)

    ARRAY TEXT($typeArr;0)

    ARRAY TEXT($valueArr;0)

  // on this node we look for the DOCTYPE type node among the

  // child nodes

    DOM GET XML CHILD NODES($refDocument;$typeArr;$valueArr)

    C_TEXT($text)

    $text:=""

    $pos:=Find in array($typeArr;XML DOCTYPE)

    If($pos>-1)

  // We retrieve the DTD declaration in $text

       $text:=$text+"Doctype: "+$valueArr{$pos}+Char(Carriage return)

    End if

    DOM CLOSE XML($rootRef)

 End if