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c#asciiwindows-cezxing

Different ASCII value for one character

I'm making a c# program which generates a QRCode with the ZXing library to be read by a Windows Mobile Handheld device (c# but proprietary barcode reader : Motorola Symbol)

I set the tag content to é (acute lowercase e) with a winform textbox and give it to read to my device, which reads Ú (acute uppercase U)

When I read the tag with the Android Barcode Scanner it reads é...

[I cannot upload images here, i'll post the barcode later]

I suppose encoding is the problem here so I took a look on the bytes sent : 233

On this website : http://www.ascii-code.com/ , it says that é is 233 which is the expected behavior. But on this website : http://www.theasciicode.com.ar/ is says that é is 130 and Ú is 233 ! (btw I'm typing Alt+233 to display Ú on my Windows computer)

EDIT : apparently the first website shows ISO-8859-1 (windows-1252) characters. But the question remains : in which encoding is é coded 130 as per the second website ?

EDIT 2 : I completely agree that UTF-8 will easily solve my problem (works with android, but I can't tell my device "Hey this barcode is UTF-8 encoded!" so it will show me raw information, see answer below.

  • What is happening ? (edit : answered, single symbol encoding mismatch)
  • Is it normal to have two specific ASCII values for one character ? (edit : answered, two encodings are used)
  • Since I receive a 233 code, how can I tell the Handheld device to convert this value ?

Thank you in advance !

Solution

  • Now I get it : the barcode reader of the device reads data in DOS 850 encoding !

    The first hint was the keyboard : by looking on the web I found that you can see your default encoding in Windows by typing the command chcp. It shows 850 on my computer. A quick googling sent me to this page : https://en.wikipedia.org/wiki/Code_page_850 where é is 130 ! Yay !

    All I had to do is tell the device to display the values as Windows-1252 charset :

    Encoding.Default.GetString(Encoding.GetEncoding(850).GetBytes(txt),0,txt.Length);

    For the general purpose of the question, thanks to @MarkGravell, the websites where falsely talking about general "extended ascii" codes, but these codes change between encodings (https://en.wikipedia.org/wiki/Category:DOS_code_pages) and are therefore irrelevant.