compression.isZip(file)
The isZip() function checks wether a file represent a valid ZIP archive.
Parameters
file
A string or a File object, to be checked for ZIP validity.
Return value
Returns true if the given file is a valid ZIP archive, false otherwise.Example
-- extract an entry from a zip archive
local compression = require "compression"
-- check parameters : the archive and entry specified as argument
local archive = arg[1] or error("no archive specified")
local entry = arg[2] or error("no entry specified")
-- check that the file is a valid ZIP archive
if not compression.isZip(archive) then
error("'"..archive.."' is not a valid ZIP archive, or may be corrupted")
end
-- open the archive
local z = compression.Zip(archive)
-- extract the entry on the disk in the current directory or throws an error if false
local extracted = z:extract(entry) or error(z.error)
print(extracted.name.." has been successfully extracted to "..extracted.path)