linq to xml, handling empty tags

The following link statement works fine if the source XML contains a number or if the tags are missing. The problem I have is when the tags are empty or if a non-numeric value is used. Can this statement be modified to handle these situations ?

Convert.ToInt32((string)Data.Elements("groupBy"开发者_运维问答).Elements("depth").FirstOrDefault() ?? "0")

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Don't know of a way to solve this with LINQ but if you cannot guarantee the content of the XML document then would it be easier to just use int.TryParse()?, e.g.

int result = 0;
int.TryParse((string)Data.Elements("groupBy").Elements("depth").FirstOrDefault(), out result);

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I would simply do:

try
    int result = (int)Data.Elements("groupBy").Elements("depth").FirstOrDefault();
catch
{
    // handle
}