Function DateDiff is not working in c#.net

Question

I am creating simples days calculation system using C#. I attached code and screen shot below. If I select the date from date and to date we need to calculate days between from date to to date to display on label control.

This is the code I tried:

private void Button1_Click(object sender, EventArgs e)
{
    int x = DateAndTime.DateDiff(DateInterval.Day, DateTimePicker1.Value.Date, DateTimePicker2.Value.Date);
}

DateDiff is not working

Answer 1

要计算两个日期的差：

double Days = (DateTimePicker2.Value.Date - DateTimePicker1.Value.Date).TotalDays;

Answer 2

this is how you can get total days between two dates.

DateTime date1 = DateTimePicker1.Value.Date;
DateTime date2 = DateTimePicker2.Value.Date;
int daysDiff = ((TimeSpan) (date2 - date1)).Days;  

in short:

int daysDiff = ((TimeSpan) (DateTimePicker2.Value.Date- DateTimePicker1.Value.Date)).Days;