对象不支持属性或方法“对话框”

I am using an .ascx user control where i populating employee data along with employee picture. while on clicking employee picture i want to display a dialog where i want to have one text field and a text box for input from user. Click event is firing fine but with dialog it gives me the error of "Microsoft JScript runtime error: Object doesn't support property or method 'dialog'". Could please anyone help me to populate a dialog with a text field and text box. I am really new to the JQUERY and struggling to get it work.I am using an .ascx user control where i popula