C＃Linq XML查找指定的元素

Question

Please could someone post an example of how to check if an element exists in an xml file using linq?

Here is the xml document:

<Database>
 <SMS>
   <Number>"+447528349828"</Number> 
   <Date>"09/06/24</Date> 
   <Time>13:35:01"</Time> 
   <Message>"Stop"</Message> 
</SMS>
 <SMS>
   <Number>"+447528349828"</Number> 
   <Date>"09/06/24</Date> 
   <Time>13:35:01"</Time> 
   <Message>"Stop"</Message> 
 </SMS>
</Database>

I want to be able to specify a number and check if it exists

Answer 1

How about:

public static bool HasNumber(XDocument doc, string number)
{
    return doc.Descendants("Number")
              .Any(element => element.Value == number);
}

(One point to note - it looks a bit odd that you've got quotes round the numbers in the XML file. Do you have to have them?)

Answer 2

I think this should do it.

var exists = xml.Descendants("Number")
                .Any(e => String.Equals(
                   (string)e, 
                   number, 
                   StringComparison.OrdinalIgnoreCase))