Linq and sql

[Ilyas]

Hi all

I have the following xml file :

<?xml version="1.0" encoding="utf-8" ?>
<root>
<persons>
<person>
<firstname>Mark</firstname>
<surname>Jones</surname>
<age>33</age>
</person>
<person>
<firstname>Adbul</firstname>
<surname>Khan</surname>
<age>30</age>
</person>
<person>
<firstname>Bob</firstname>
<surname>Smith</surname>
<age>31</age>
</person>
</persons>
</root>

I have the following expression

XElement myXml = XElement.Load("Sample.xml");

var allPersonsInOrderOfAge = from person in
myXml.Descendants("person") orderby person.Element("age") select
person;

However when I run this - I get an error saying "At least one object
must implement IComparable"

Can anyone shed any light on this? Is my expression wrong... How can I
correct this problem?

Many thanks

 

[David R. Longnecker]

var allPersonsInOrderOfAge = from person in

myXml.Descendants("person") orderby person.Element("age") select
person;

You need to cast your person.Element("age") to a type so it knows how to
compare the elements:

var allPersonsInOrderOfAge =
from person in myXml.Descendants("person")
orderby (int)person.Element("age")
select person;

Hope this helps.

-dl