Not Getting ReadOnly/Disabled textbox value on server side ASP.Net

Problem:

I am not able to get values of a textbox which is readonly on server side when click submit.

Values in the textbox fills from the date picker control.

Solution:

First of all don’t disabled or readonly textbox from design view. Add the below code on page load. 

txtExiprationDate.Attributes.Add(“readonly”, “readonly”);