c# - check value exists in linq -

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this xml file

<persons>   <person>     <id>1</id>     <name>ingrid</name>   </person>   <person>     <id>2</id>     <name>ella</name>     </person> </persons>

i using linq xml.

here id should auto-generated..

i need check if value of node id exists .

if not exists should create new id..how using linq. pointers?

thank you

    xdocument doc = xdocument.parse(xml);      int id = 1;     // if need element     xelement ingrid = (from person in doc.root.elements("person")                        (int)person.element("id") == id                        select person).firstordefault();     // if need know if there     bool exists = (from person in doc.root.elements("person")                        (int)person.element("id") == id                        select person).any();     // generate new id     int newid = ((from person in doc.root.elements("person")                   select (int?)person.element("id")).max() ?? 0) + 1;

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