I have a app that queries if the value in a textbox is valid. Validation is done on each keyup. Problem is in this:

0) Valid input is "dojofile.data"
1) User types one letter at a time and writes "dojofile.data".
2) The data sent is "d", then "do" then "doj", then "dojo" etc.
3) At some point, the last two are sent, "dojofile.dat" and "dojofile.data".