c# - Datepicker between two ages 21 and 25 wpf -

i have made application user selects there date of birth using datepicker. user must on 21 , under 26. if user on 21 , under 26 message box appears saying "success". when select date of birth between 21 , 25 nothing happens. not sure i'm doing wrong here think minusing 21 , 26 selected date in datepicker

my code fallows

xaml

<datepicker horizontalalignment="center" name="dpkdob" grid.column="1" verticalalignment="top" grid.row="10" /> 

xaml.cs

  datepicker dp = new datepicker();              datetime dateminimum = dpkdob.selecteddate.value.addyears(-21);             datetime datemaximum = dpkdob.selecteddate.value.addyears(-26); // 26, include below 26 years old             datetime birthdate = convert.todatetime(dp.selecteddate);              if (birthdate > dateminimum && birthdate < datemaximum)             {                 messagebox.show("success");             } 

you picked wrong datepicker comparison:

datetime birthdate = convert.todatetime(dp.selecteddate); 

should

datetime birthdate = convert.todatetime(dpkdob.selecteddate); 

according comments:

datetime birthdate = convert.todatetime(dpkdob.selecteddate);  if(birthdate > datetime.now.addyears(-26) && birthdate < datetime.now.addyears(-21)) {     // stuff } 

if need more in solution, think extension this:

public static class extensions {     public static timespan age(this datetime dt)     {         return (datetime.now - dt);     }      public static int years(this timespan ts)     {         return (int)((double)ts.days / 365.2425);     } } 

usage:

datetime birthdate = convert.todatetime(dpkdob.selecteddate);  if (birthdate.age().years() > 21 && birthdate.age().years() < 26) {     // stuff }