String Encode in C++

Question

I need to convert the string "Test €" to "Test &#8364 ;" and vice versa. Please make a note that its a string and not from the xml. For your information I am developing the application in C++ and using Xerces also for XML Parsing. Please help me how it can be achieved in c++ application.

Thanks, Ram

Too broad. What have you tried? Did you write your own conversion method and it does not work? Are you trying to use some library and have problems with that? — Daniel Frey, Mar 07 '13 at 06:52
I haven't write my own conversion methods and I can use some library to achieve that. — Ram, Mar 07 '13 at 07:00
Possible Dup: http://stackoverflow.com/questions/154536/encode-decode-urls-in-c — Daniel Frey, Mar 07 '13 at 07:03
I'm pretty sure that's not a duplicate; this isn't asking about URL's... — Kyle Strand, Mar 07 '13 at 07:04
How is the original string represented and encoded? And is it a srring literal in a source file, or is it read in from a text file, or does it come from keyboard input or something else? — Bingo, Mar 07 '13 at 07:05
Yes. Its not encoding the URL. Converting unicode characters to xxx and vice versa. — Ram, Mar 07 '13 at 07:06
User will key-in 100 € ; from the keyboard (command prompt) and need to store that into the database. If I change the value in the database to 200 € then it should be sent to the command prompt in the way that 200 € ; — Ram, Mar 07 '13 at 07:11
Oh, sorry, it's called HTML encoding, not URL encoding, right? — Daniel Frey, Mar 07 '13 at 07:30
Whoa, you're using unicode to let users specify a currency type? — Kyle Strand, Mar 07 '13 at 07:55
yes. This is will be received from some other application through tcp/ip protocol to my application. so the other application will send xxx instead of unicode characters. In my app I need to encode it and store into the db. — Ram, Mar 07 '13 at 08:00

Kyle Strand · Accepted Answer · 2013-03-07T07:12:55.827

I think this answer may be platform-dependent, though I don't know for sure.

You can use stringstreams and casting. If lookup is a string holding the decimal version of the character code, this function will return the character version:

char fixchar(string lookup){
    stringstream converter (lookup);
    int i;
    converter >> dec >> i;
    return (char)i

(Note that for hex strings, which are prefixed with #x instead of #, you can just use hex instead of dec).

You can get the lookup strings by using the find function on the original string. Here's a loop that uses the above function to convert a string (called fixd) with &#x[number] substrings into a normal string with no character codes:

while (fixd.find("&#x")!=string::npos){
    tag = int(fixd.find("&#"));
    endtag = int(fixd.find(";"));
    fixd = fixd.substr(0,tag) + fixchar(fixd.substr(tag+3,endtag-tag-3)) + fixd.substr(endtag+1, fixd.length()-tag-4);
}

Similarly, you should be able to get the int version of a character just by casting it, after which you can do whatever you want with it, including adding it in decimal form to a string.

Thanks Kyle. I am testing this and let you know my result shortly. — Ram, Mar 07 '13 at 07:52
Thanks and its working fine. I just changed fixchar() method to return back wchar_t instead of char. Also fixd is treated as wstring. — Ram, Mar 12 '13 at 07:46

String Encode in C++

1 Answers1