Unicode (std::wstring) with TinyXML

[Erdem]

Hi,

I'm converting my to support other languages so I am moving my strings from std::string to std::wstring.

Previously I was able to do the following:

                entry3.InsertEndChild( TiXmlText( (*i)->getDescription( lang ) ) );

getDescription() used to return a std::string and it worked nicely.

Now it is returning a std::wstring and it doesn't compile anymore:

..\..\ext\TinyXML\tinyxml.h(488) : error C2440: 'return' : cannot convert from 'const wchar_t *' to 'const char *'

Obviously this is expected. But it says on the TinyXML page that UTF-8 is supported, how can I use std::wstring with Tiny XML ?

Thanks,

MDE

[James Lawrence]

TinyXML (both TinyXML and TinyXML-2) primarily deals with narrow character strings (std::string). However, if you want to work with Unicode strings (std::wstring), you need to convert between std::wstring and std::string (typically using UTF-8 encoding).

Steps to handle Unicode (std::wstring) with TinyXML:
Convert std::wstring to std::string (UTF-8) before inserting into TinyXML.
Convert std::string (UTF-8) back to std::wstring when reading from TinyXML.
Implementation:
Dependencies:
Use <codecvt> (deprecated in C++17, removed in C++20) or std::wstring_convert
Use TinyXML (or TinyXML-2)
Example with TinyXML (Legacy):
cpp
Copy
Edit</codecvt>

include <iostream></iostream>

include <string></string>

include <locale></locale>

include <codecvt></codecvt>

include "tinyxml.h"

// Helper function to convert std::wstring to UTF-8 std::string
std::string WStringToUtf8(const std::wstring& wstr) {
std::wstring_convert<std::codecvt_utf8\<wchar_t>> converter;
return converter.to_bytes(wstr);
}</std::codecvt_utf8\<wchar_t>

// Helper function to convert UTF-8 std::string to std::wstring
std::wstring Utf8ToWString(const std::string& str) {
std::wstring_convert<std::codecvt_utf8\<wchar_t>> converter;
return converter.from_bytes(str);
}</std::codecvt_utf8\<wchar_t>

int main() {
TiXmlDocument doc;

// Create XML declaration
TiXmlDeclaration* decl = new TiXmlDeclaration("1.0", "utf-8", "");
doc.LinkEndChild(decl);

// Create root element
TiXmlElement* root = new TiXmlElement("Root");
doc.LinkEndChild(root);

// Unicode string (wstring)
std::wstring unicodeText = L"Привет, мир! 🌍"; // "Hello, world!" in Russian + Emoji

// Convert to UTF-8 and insert into XML
TiXmlElement* messageElement = new TiXmlElement("Message");
messageElement->LinkEndChild(new TiXmlText(WStringToUtf8(unicodeText).c_str()));
root->LinkEndChild(messageElement);

// Save to file or print to console
doc.SaveFile("unicode_example.xml");

// Read back the value
TiXmlElement* retrievedElement = root->FirstChildElement("Message");
if (retrievedElement) {
    std::wstring retrievedWString = Utf8ToWString(retrievedElement->GetText());
    std::wcout << L"Retrieved Text: " << retrievedWString << std::endl;
}

return 0;

}
Explanation:
Converts std::wstring to UTF-8 std::string before inserting into TinyXML.
Saves XML in UTF-8 format.
Reads XML data and converts UTF-8 std::string back to std::wstring for proper Unicode handling.
Notes:
std::wstring_convert is deprecated in C++17. For modern C++, consider std::codecvt_utf8 with std::wstring_convert alternatives like ICU or std::wstring-compatible libraries.
TinyXML-2 works similarly, but you would use tinyxml2::XMLElement and tinyxml2::XMLText.
Would you like an updated example for TinyXML-2? �