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POHow to properly convert char* into std::string? (issues while using expat / std::string(char*))
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copied!<h2>Problem Description</h2> <p>I'm using Expat with a custom C++ wrapper, which I already tested on other projects. I'm running into problems, because the original data (c_str) is not converted to a std::string in the right way. This concers me, because I did not change the source of the wrapper.</p> <p>It seems like the string gets null-terminated chars after this conversion:</p> <pre><code>onCharacterData( std::string( pszData, nLength ) ) // --> std::string( char* pszData) </code></pre> <p>How can I fix this? </p> <h2>Own expat wrapper</h2> <pre><code>// Wrapper defines the class Expat and implements for example: void XMLCALL Expat::CharacterDataHandler( void *pUserData, const XML_Char *pszData, int nLength ) { Expat* pThis = static_cast<Expat*>( pUserData ); // XML_Char is char, therefore this call contains i.e.: std::string("hello", 5) pThis->onCharacterData( std::string( pszData, nLength ) ); } </code></pre> <h2>Custom parser</h2> <pre><code>// Parser is defined as: class Parser : Expat void Parser::onCharacterData(const std::string& data ) { // data is no longer char*, but a std::string. // It seems to contain \0 after each character which is wrong! // [...] } </code></pre> <h2>Character data within the expat wrapper (char*)</h2> <p><img src="https://i.stack.imgur.com/hBKrD.jpg" alt="Character data within the expat wrapper (char*)"></p> <h2>Character data within the parser (std::string)</h2> <p><img src="https://i.stack.imgur.com/jGKP9.jpg" alt="Character data within the parser (std::string)"></p>

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