返回使用LINQ

Question

我應該返回的參數傳遞的元素的ID，像一個功能元素的ID：

public static Int32 getIdByName(string name) 
{ 
    var query = from student in DataAccess.getInstance.StudentSet 
       where student.FirstName.Equals(name) 
       select student; 

    return toto; 
} 

我不知道如何將結果toto轉換爲Int32並返回它！

Answer 1

return DataAccess.getInstance.StudentSet.Last(s => s.FirstName == name).Id; 

Answer 2

public static Int32 getIdByName(string name) 
{ 
    var query = from student in DataAccess.getInstance.StudentSet 
       where student.FirstName.Equals(name) 
       select student.Id; 

    return query.First(); 
}