Checking for file extensions

Question

I have a form that I want to submit a csv file to, however I would like to check the file to make sure that it is indeed .csv before I perform the task that I need to do
*****************Example***********************
form.html
<form name=vo_verify action=verify.jsp method=post>
<input type=file>
<input type=submit>
</form>
verify.jsp
return true == .csv
return false != .csv

Answer 1

Could you do a check for the substring within the filename?
Like,
String filename = (String)request.getParameter("file");
int index = filename.indexOf(".csv");
if (index == -1) do something; //extension .csv not found
else do something else;
There might be a better way to do this, but this should work I think.
Also, bdtjdc was just trying to help, which is what this forum is for. :)