you should also send data in json with POST method. it’s pretty easy to use that data in php on the server side.
never had a problem with that.
Unfortunately, the socket.url.escape did not work with the national characters like æøå/äöü so I have to use the string = mime.b64(string) that XedurR suggested. But I also had to avoid a lot of characters that can be entered with the English/Norwegian and German keyboard that we at the moment will support.
I am using MySQL Database and PHP 7.2.7 and I have problems saving e.g. the the backslash (), percent (%) and the combination ("/>")
On the Server I am therefore looping through all the request variable from GET or from POST and decode the values ($value = base64_decode($value), convert some values back to what they should be before the data is saved.
Here is the code that I use to remove/replace characters that cause problems on the Server:
removeCharsWithError = function(newChar) local mime = require("mime") local replaceChar = "" local theAscii = string.byte(newChar) or -1 local theb64 = mime.b64(newChar) or -1 if theAscii == 92 then -- backslash "\" replaceChar = "/" elseif newChar =="°" then -- degree -- works on Mac Simulator replaceChar = "\*" elseif theAscii == 203 then -- degree -- Ascii value = 194 on Mac, 203 on iPad replaceChar = "\*" elseif theb64 == "y5o=" then -- degree -- theb64 value = "wrA=" on Mac, "y5o=" on iPad replaceChar = "\*" elseif newChar =="•" then replaceChar = "-" elseif newChar =="±" then -- works on Mac Simulator replaceChar = "+/-" elseif theb64 == "4omg" then --on iPad replaceChar = "+/-" end -- variations of letters --on iPad -- A if theb64 == "xIA=" then -- Overline replaceChar = "A" elseif theb64 == "xIE=" then replaceChar = "a" -- E elseif theb64 == "xJY=" then -- One dot replaceChar = "E" elseif theb64 == "xJc=" then replaceChar = "e" elseif theb64 == "w4s=" then -- Two dots - German keyboard replaceChar = "E" elseif theb64 == "w6s=" then replaceChar = "e" elseif theb64 == "xJg=" then -- Polish E replaceChar = "E" elseif theb64 == "xJk=" then replaceChar = "e" elseif theb64 == "xJI=" then -- Overline replaceChar = "E" elseif theb64 == "xJM=" then replaceChar = "e" -- U elseif theb64 == "xao=" then -- Overline replaceChar = "U" elseif theb64 == "xas=" then replaceChar = "u" -- I elseif theb64 == "xKo=" then -- Overline replaceChar = "I" elseif theb64 == "xKs=" then replaceChar = "i" elseif theb64 == "xK4=" then -- La cédille - English keyboard replaceChar = "I" elseif theb64 == "xK8=" then replaceChar = "i" -- O elseif theb64 == "xYw=" then -- Overline replaceChar = "O" elseif theb64 == "xY0=" then replaceChar = "o" -- S elseif theb64 == "xZo=" then -- accent aigu replaceChar = "S" elseif theb64 == "xZs=" then replaceChar = "s" -- C elseif theb64 == "xIw=" then -- c with caron replaceChar = "C" elseif theb64 == "xI0=" then replaceChar = "c" elseif theb64 == "xIY=" then -- accent aigu replaceChar = "C" elseif theb64 == "xIc=" then replaceChar = "c" elseif theb64 == "w4c=" then -- cedilla replaceChar = "C" elseif theb64 == "w6c=" then replaceChar = "c" -- N elseif theb64 == "xYM=" then -- accent aigu -- German keyboard replaceChar = "N" elseif theb64 == "xYQ=" then replaceChar = "n" -- Z elseif theb64 == "xbk=" then -- accent aigu -- English keyboard replaceChar = "Z" elseif theb64 == "xbo=" then replaceChar = "z" elseif theb64 == "xbs=" then -- with caron -- English keyboard replaceChar = "Z" elseif theb64 == "xbw=" then replaceChar = "z" -- L elseif theb64 == "xYE=" then -- with slash through -- English keyboard replaceChar = "L" elseif theb64 == "xYI=" then replaceChar = "l" end return replaceChar end
My Textlistener to remove or replace all characters that cause a problem looks like this:
local function textListener(event) if (event.phase == "began") then theEnteredText = event.target.text elseif event.phase == "editing" then -- Remove unwanted characters local newChar = event.newCharacters -- local oldText = event.oldText this does not work if event.oldText contains characters like \ local replaceChar = "" if newChar then replaceChar = removeCharsWithError(newChar) if theEnteredText == "" and replaceChar ~= "" then event.target.text = replaceChar elseif replaceChar ~= "" then event.target.text = theEnteredText..replaceChar end replaceChar = "" end theEnteredText = event.target.text -- END Remove unwanted characters end end
On the App I convert the values that are to be sent with this code:
(The combination “/>” is also causing a problem)
local doEncode = function(theString) if theString ~= "" then -- %% in lookfor is replaced with single % lookfor = '%%'; replacewith = "!!!PERCENT!!!" theString = string.gsub(theString,lookfor,replacewith); lookfor = '/\>'; replacewith = "/XXXgtXXX" theString = string.gsub(theString,lookfor,replacewith); local mime = require("mime") theString = mime.b64(theString) end return theString endI don’t understand why you need all that. I have a similar configuration to you and it works with all character sets (including CJK).
I use the utf8 library rather than the standard string library. I then use this function to remove the problematic chars - those with a code point above 65535 and then POST to my server.
function stripProblemChars(s) local res = "" for i = 1, utf8.len(s) do local c = utf8.sub(s, i, i) if utf8.codepoint(c) \<= 65535 then res = res .. c end end return res end
I use utf8_general_ci for the database and have never had a “string problem”.
It’ll be easier to just use mime.
local mime = require("mime") local string = "/^s.-!%)\\'" print(string) -- output: /^s.-!%)\' string = mime.b64(string) print(string) -- output: L15zLi0hJSlcJw== string = mime.unb64(string) print(string) -- output: /^s.-!%)\'
Using mime’s base64 encoding and decoding you can make any string safe to submit in a URL. All you need to do is encode at source, send and decode at destination.
you can change the text you replace with a text that gsub works, for example:
local theDescription = “some text ####BACKSLASH#### and some more text”
local lookfor = “####BACKSLASH####”;
local replacewith = ‘\’;
theDescription = string.gsub(theDescription,lookfor,replacewith);
print (theDescription)
Sorry carloscosta
theDescription = "some text -###BACKSLASH###- and some more text" local lookfor = "-###BACKSLASH###-"; local replacewith = '\\'; theDescription = string.gsub(theDescription,lookfor,replacewith); print(" theDescription: "..theDescription)
gives this:
– Output: theDescription: some text \#- and some more text
Am I missing something? :huh:
If your issue is with URL strings becoming malformed, all you need to do is use base64 encoding with them as in my sample code above. You don’t need to play around with gsub or anything.
Thank XeduR, do you have an example on how to encode it using PHP 7.2 so that I can store the data in the MySQL database ?
Thanks, again XeduR,
I have managed to implement the decode in the App and the encode on the PHP on the Server.
But, I still have a problem with the bakslash ().
If I enter e.g. "abc " into a native.NewTextField() and read the value
local theValue = theCustomerDescriptionField.text -- abc \ print(theValue) -- output: abc \\Ah, yeah. Those occur because backlashes are used to escape characters in Lua. I’m guessing that your string is automatically “fixed” for you somewhere since you can’t actually have a string like "abc " in Lua because it would be an unfinished string.
So, if you have string like “abc \” it will appear as "abc " if you output it, but you can’t actually turn it into "abc " because it just won’t work (unfinished string again). You could, if you want, change the “\” into “/” by looping through the entire string, character by character. Do you have a specific need to do this?
Just to sum up again what my problem is:
I enter “abc\test” into an entryfield. Looking at the value of the entry field, it has changed to “abc\test”
I try to replace a single “”, but Corona or ZeroBrane requires that I escape the character, so I replace it as follows.
lookfor = '\\'; replacewith = "-!!!BACKSLASH!!!-" theString = string.gsub(theString,lookfor,replacewith); print theString -- output: abc-!!!BACKSLASH!!!-test
When I try to read the information back (from the MySQL database) I try to do the reverse:
local lookfor= "-!!!BACKSLASH!!!-" local replacewith = '\\'; theDescription = string.gsub(theDescription,lookfor,replacewith); print theDescription -- output: abc\\!-test
the “print” function shows two backslashes (but in the entryField it is shown as one)
However, the problem now is that the string.gsub() does not remove the complete text, “!-” is still left after the replace has been done.
The need for this is an app where the user should be able to enter any character into textfields and these should be saved in the database and later shown in the App and on a website.
I have already decided to filter out the single ^-character, and I have to replace the Eurosign (€) since it cannot be saved in the database when I use PHP.
The reason as to why “abc\test” from your entryfield changes to “abc\test” is because a lone backslash cannot exist in a lua string. It will always break the string. The function that you are using is adding the extra backslash there to prevent the string from being broken.
i.e. if a user inputs a string “abc\test” it will be stored as “abc\test”, but if you later create a display object with that, the display object will still read as “abc\test”.
I would personally just prevent the users from submitting any such special characters. This will usually save you a lot of time and money from needing to worry about these issues. Unless there is a specific need to allow the user to type in those characters, you can filter them out by using something like “if char:find(”%w") or char == " " then" to check that the newly inputted character is either an alphanumeric character or a space. You could add punctuation there for the checks as well, etc.
It might be a good idea to at least stop the user from entering some difficult characters, but it is hard to know what they all are since the user might be using different national keyboards with very different characters.
I have tried however, to replace the \ with a /, but the textlistener event = “editing” is also having problems
local newChar = event.newCharacters local oldText = event.oldText if newChar then if newChar == "\\" then if oldText ~= nil then event.target.text = "/" else event.target.text = oldText.."/" end end end
When I enter a \ the event.oldText becomes “nil”
(I could maybe remember the event.oldText in a variable, but it shows the problems with the backslash)
Can you compare newChar to the character code for “” rather than a literal string?
Yes, it looks like I have to do that. I am not happy about it since the customer should be able to enter any type of text.
But it looks like I have to implement this code:
-- theEnteredText is set to event.target.text when event.phase == "began" local newChar = event.newCharacters local oldText = event.oldText if newChar then local theAscii = string.byte(newChar) if theAscii == 92 then if theEnteredText == "" then event.target.text = "/" else event.target.text = theEnteredText.."/" end end end theEnteredText = event.target.textThis might work easier
-- Contruct an URL compatable string from a table of parameters -- @param table params The parameters to be used in {paramName = paramValue, etc} format. local urlOperations = require("socket.url") local urlEncode = urlOperations.escape function paramsToString(params) local paramsString = "" for name, value in pairs(params) do if value then value = urlEncode(tostring(value)) if string.len(value) \> 0 then -- No empty values are to be sent paramsString = paramsString .. name .. "=" .. value .. "&" end end end return paramsString endI took a few minutes to adjust the sample code from Corona docs. This is how I’d approach the issue:
[lua] local defaultField local acceptedString, character = "", "" local textObject = display.newText( "", display.contentCenterX, display.contentCenterY-40, system.defaultFont, 32 ) local function textListener( event ) if event.phase == "editing" then acceptedString = "" for i = 1, event.newCharacters:len() do character = event.newCharacters:sub(i,i) if character:find( "%w") or character == " " then -- %w is alphanumeric characters acceptedString = acceptedString..character end end textObject.text = acceptedString end end defaultField = native.newTextField( display.contentCenterX, display.contentCenterY, 180, 30 ) defaultField.inputType = "no-emoji" defaultField:addEventListener( "userInput", textListener ) [/lua]
This way, you’d loop through the string whenever new characters are entered. In the loop, you’d only accept alphanumeric characters and spaces. If you want to accept or reject some other types of characters or specific characters, you can just add them to the check (for character classes, see https://www.lua.org/pil/20.2.html). Alternatively, you could just watch out for things that you definitely don’t want and block those out.
Thank you all. I will try to implement it to avoid characters that cause problems.