\samp{form.getvalue(\var{key})} would return a list of strings.
If you expect this possibility
(when your HTML form contains multiple fields with the same name), use
-the \function{isinstance()} built-in function to determine whether you
-have a single instance or a list of instances. For example, this
+the \function{getlist()} function, which always returns a list of values (so that you
+do not need to special-case the single item case). For example, this
code concatenates any number of username fields, separated by
commas:
\begin{verbatim}
-value = form.getvalue("username", "")
-if isinstance(value, list):
- # Multiple username fields specified
- usernames = ",".join(value)
-else:
- # Single or no username field specified
- usernames = value
+value = form.getlist("username")
+usernames = ",".join(value)
\end{verbatim}
If a field represents an uploaded file, accessing the value via the