local function urlEncode(s)     
	s = string.gsub(s, "([^%w%.%- ])", function(c) 
	return string.format("%%%02X", string.byte(c)) end)    
	return string.gsub(s, " ", "+")
end 
local function urlDecode(s)    
	s = string.gsub(s, '%%(%x%x)', function(h) 
	return string.char(tonumber(h, 16)) end)    
	return s
end

str = urlEncode("https://mp.csdn.net/mdeditor#")
print(str);
print(urlDecode(str));