The accidental complexity of working with the DOM is so high that many programmers are giving
up on using XML altogether, cursing the hype that XML makes dealing with data simple, which no one who
has actually written DOM code could claim. The W3C DOM was not designed with ease of programming in
mind, but rather evolved as a design by committee from the existing DHTML object model originally created by Netscape.
Consider the following simple purchase order document
<div style="border:5px dashed #00FF00;
background-color:#FF0000;
padding: 7px; width:
auto;">
<purchaseOrder orderDate="2013-05-26">
<shipTo country="Indonesia">
<name>Andre Firman</name>
<street>Danau Ranau Street</street>
<city>Malang</city>
<state>East Java</state>
<zip>65148</zip>
</shipTo>
<billTo country="Indonesia">
...
</billTo>
<items>
<item partNum="872-AA">
<productName>Spark Board</productName>
<quantity>1</quantity>
<price>Rp.142.000</price>
</item>
...
</items>
</purchaseOrder>
</div>
The DOM implementation as surfaced in the .NET frameworks as the System.Xml.XmlDocument API is
extremely imperative, irregular, and complex. Nodes are not first class citizens and have to be created and
exist in the context of a given document. To construct this document using the DOM, we must first create a new document as a root for all other nodes we will create. Then we find that creating and inserting child
nodes requires two imperative steps. One to create a new child element or attribute, and a second to then
insert the just created node into the parent.
<div style="border:5px dashed #00FF00;
background-color:#FF0000;
padding: 7px; width:
auto;">
Dim PO As New XmlDocument
Dim purchaseOrder As XmlElement = _
PO.CreateElement("purchaseOrder")
PO.AppendChild(purchaseOrder)
Dim orderDate XmlAttribute = _
PO.CreateAttribute("orderDate")
orderDate.Value = "1999-10-20"
purchaseOrder.Attributes.Append(orderDate)
Dim shipTo As XmlElement = _
PO.CreateElement("shipTo")
purchaseOrder.AppendChild(shipTo)
Dim country As XmlAttribute = _
PO.CreateAttribute("country")
country.Value = "US"
shipTo.Attributes.Append(country)
...
</div>
This is unfortunate for readability, debuggability, and maintainability, because now there is no helpful relationship between the structure of the code we write and the structure of the XML we need to create.
The access patterns for attributes and elements are gratuitously different, and the handling of namespaces is confusing at best. Finally even pretty-printing an XML document takes several lines of arcane and complex
code since the .ToString() method is not properly overridden.
