hi, you can read like below

string value = Request.Form[TextBox1.UniqueID];

or else you can set Readonly at run time like below

TextBox1.Attributes.Add("readonly", "readonly");

Refer : http://forums.asp.net/t/1485723.aspx/1?readonly+TextBox+value+not+able+to+retrieve+in+codebehine

http://forums.asp.net/t/1477749.aspx/1?textbox+problem