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new XML

var oXml = new XML(“<person><name>Nicholas C. Zakas</name></person>”);

The second way is to use the syntax extension mentioned earlier, allowing you to enter the XML directly

into the code without using strings:

var oXml = <person>

<name>Nicholas C. Zakas</name>

</person>;

The XML is interpreted according to several flags on the

XML

constructor:

XML.ignoreComments

— If set to

true

, causes the parser to ignore comments

XML.ignoreProcessingInstructions

— If set to true, causes the parser to ignore processing

instruction.

XML.ignoreWhitespace

— If set to true, causes the parser to ignore whitespace between

elements

The

toString()

method is accompanied by the

toXMLString()

method, both of which returns string

representations of the XML. The

toString()

method returns an XML-encoded string if the element

contains complex children (that is, anything other than text); if the element contains only simple content

(text), then

toString()

just returns the text without the start and end tags. On the other hand,

toXMLString()

always returns the XML tags regardless of the element’s children. For example:

var oXml = <name>Nicholas C. Zakas</name>;

alert(oXml.toString()); //outputs “Nicholas C. Zakas”

alert(oXml.toXMLString()); //outputs “<name>Nicholas C. Zakas</name>”;

In the previous code, the first alert displays just

“Nicholas C. Zakas”

because the

toString()

method is called. The second alert displays the full XML code,

“<name>Nicholas C. Zakas</name>”

If, however, the element has complex content, both methods return the same value:

var oXml = <name><first>Nicholas</first><last>Zakas</last></name>;

alert(oXml.toString()); //outputs

“<name><first>Nicholas</first><last>Zakas</last></name>”

alert(oXml.toXMLString()); //outputs

“<name><first>Nicholas</first><last>Zakas</last></name>;”;

In this code,

toString()

and

toXMLString()

return

“<name><first>Nicholas</first><last>Zakas</last></name>”

Both methods use a variety of settings on the XML constructor to determine how to output the XML code:

XML.prettyPrinting

— When set to

true

, the methods normalize whitespace between

elements.

XML.prettyIndent

— Specifies the line indent in the methods. By default this is set to

All the constructor flags are stored in an object that can be referenced by using the

XML.settings()

method. This object can then be used to restore the settings later by using the

XML.setSettings()

method, as shown in this example:

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