Re: Cross Platform/Browser way to send PNG file to Webserver
On 3/16/2010 7:55 AM, Peter Olcott wrote:
I want to sent a 24-bit PNG file to a web service that I
will be writing. In the ideal case the user will go to my
website and click on a button that will browse their local
hard-drive for a PNG file. This file is then verified to be
24-bit on the client side. If it is 24-bit it is then sent
to the web-service. If it is not 24-bit an error message is
displayed "The PNG file selected must have 24-bit color".
Can this be done in either JavaScript or Java?
I'm not an expert on PNG files, but I'm sure it is possible to read a
PNG file and determine that it is 24 bit with Java. Sending it to your
website is no problem. The issues come with how. Java Applets need to
be signed to get at the local file system. HTML can send a file as Ivan
suggested but the browser won't be able to determine whether or not it
is a 24 bit file. So my suggestion would be to use HTML to send the
file and write a perl or php CGI program to run on your web server to
read the file. If it is 24 bit accept it if not discard it and display
a message to the user that it wasn't a 24 bit file.
--
Knute Johnson
email s/nospam/knute2010/