An attribute value can be set so that it can have any string of text. However, the "<", ">", """, or "&" can not be used.
<?xml version="1.0" standalone="yes"?> <!DOCTYPE rootelement [ <!ELEMENT rootelement (childelement1)> <!ELEMENT childelement (#PCDATA)> <!ATTLIST childelement sampleattribute CDATA "0" ]> <rootelement> <childelement sampleattribute="A CDATA attribute value."> Child element. </childelement> </rootelement>