how to get textbox value from front end to crystal report

Question

hi

 i  have  the textboxes  say txtfromdate and txttodate  these to textboxes are on front end forms(no db connection) and 

i want to get these text box values as it is on crystal reports header section how to get it please help

i have written code:

 i created the formula 

 repexamdesc.DataDefinition.FormulaFields["fromdate"].Text = "" + txtfromdate.Text + "";

 repexamdesc.DataDefinition.FormulaFields["todate"].Text = "" + txttodate.Text + "";

where

repexamdesc=reportobject

fromdate=formula field

todate=formula field

this gives me answer in int fomat i.e if my fromdate textbox value is 6/1/2012 then 

it shows output as = 6

 it dosent  take '/'  since my formula fields(fromdate,todate) have data type int 16

how to its value to varchar

please help

any other solution will be greatly appreciated.