如何使用datepicker C＃检查用户是否在21到25之间

Question

我正在使用wpf创建一个应用程序，用户在datePicker上选择他们的DOB，然后检查用户是否在21到25之间。如果用户显示MessageBox说“成功“如果没有表现出来。我该怎么计算出来

Answer 1

// Just an example obj for the code.
datePicker dp = new DatePicker();

dateMinimum = DateTime.Now.AddYears(-21);
dateMaximum = DateTime.Now.AddYears(-26); // 26, as this would include somebody whose just below 26 years old
birthDate = dp.SelectedDate;

if (birthDate > dateMinimum && birthDate < dateMaximum) {
    MessageBox.Show("Success");
}