您必须首先在 c-string 中执行此操作,然后将其复制到 std::string 中: char buff[100]; snprintf(buff, sizeof(buff), "%s", "Hello"); std::string buffAsStdStr = buff; 但我不确定你为什么不只使用字符串流?我假设您有特定的理由不只是这样做: std::ostringstream stringStream; stringStream << "...
I figured it out. I just create a temporary char[], I do the writing into it and then assign the contents of the char[] string into the std::string. The code goes like this: 1 2 3 4 5 charss[] ="a string"; std::string sd;charstemp[100] =""; snprintf(stemp, 100,"This ...
The format string consists of ordinary byte characters (except %), which are copied unchanged into the output stream, and conversion specifications. Each conversion specification has the following format: introductory % character. (optional) one or more flags that modify the behavior of the ...
The snprintf subroutine converts, formats, and stores the Value parameter values, under control of the Format parameter, into consecutive bytes, starting at the address specified by the String parameter. The snprintf subroutine places a null character (\0) at the end. You ...
Format-controlstring argument Optionalarguments Remarks Thesscanffunction reads data frombufferinto the location given by eachargument.Everyargumentmust be a pointer to a variable with a type thatcorresponds to a type specifier informat. Theformatargumentcontrols the interpretation of the input fields and...
3. What is a "std::to_string"? One last thing... 4. I noticed you changed the function signature, so that the last parameter is a "const std::string&" and have left the first parameter as "std::string". Is there a specific reason you have done this?
don't you run into memory manager issues when using streams in executables and/or one or more DLLs? The original poster wanted a way to format data to a string; stringstream fits the bill while being portable and easy to use safely. Memory manager issues? Not any more than other code i...
std::vector<std::string> names; if (condOutput || currOutput) { outputStepNum = secondLevelManager_->getStepNumber(); netlistFile = commandLine_.getArgumentValue("netlist"); sprintf(tmp, "%03d", outputStepNum); tmp.width(3); tmp.fill('0'); tmp << outputStepNum; int numElectrodes...
The third argument to memset, which specifies the number of bytes to write, is a ternary expression, of which the significant part is the false block that follows the colon: ((_Size) - (_Offset))) * sizeof(*(_String)). Substituting the macro arguments into the expression yields the fo...
wrap_sprintf( char* strDest, char* strFmtString, ... ) { va_list args; va_start( args, strFmtString ); vsprintf( stdDest, strFmtString, args ); va_end( args ); } That's likely all you need. But if you think you really need to determine sizes, then read on. To manually...