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sqlite3_column_text returns a const unsigned char*, how do I convert this to a std::string? I've tried std::string(), but I get an error.
Code:
temp_doc.uuid = std::string(sqlite3_column_text(this->stmts.read_documents, 0)); Error:
1>.\storage_manager.cpp(109) : error C2440: '<function-style-cast>' : cannot convert from 'const unsigned char *' to 'std::string' 1> No constructor could take the source type, or constructor overload resolution was ambiguous 
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You absolutely can assign const char* to std::string , it will get copied though. The other way around requires a call to std::string::c_str() .
const char* is useful for pointer to a string that will not change. ie your program will print some string, like the same welcome messages every time it starts. The unsigned version is useful for pointer to a binary sequence you may want to write too a file.
Use std::string when you need to store a value. Use const char * when you want maximum flexibility, as almost everything can be easily converted to or from one.
You can use the c_str() method of the string class to get a const char* with the string contents.
You could try:
temp_doc.uuid = std::string(reinterpret_cast<const char*>( sqlite3_column_text(this->stmts.read_documents, 0) )); While std::string could have a constructor that takes const unsigned char*, apparently it does not.
Why not, then? You could have a look at this somewhat related question: Why do C++ streams use char instead of unsigned char?
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