Hi Prasanna,
Thank you for your interest in Syncfusion Products.
The DropDownCalendar control offers various pre-defined formats, in which the date-time values can be displayed, by setting the required option to the Format property which represents the date-time format of the control with the options of Long, Short, Time, CustomChar and CustomString. In order to set the date format as MM/dd/yyyy, please refer the code snippet below.
[ASPX]
Format="CustomString"
CustomFormat="MM/dd/yyyy">
For Calendar control, the date format 'MM/dd/yyyy' can be set as,
TextBox1.Text = Calendar1.SelectedDate.ToShortDateString();
Also please refer the sample files below to achieve this.
http://websamples.syncfusion.com/samples/Grid.Web/6.4.0.15/F78810-Calendar/Grid_Web_CalendarFormat.zipPlease let me know if this helps you.
Thanks,
Rekha