如何将float转换为string

     可能有好多人，包括C语言老手都不知道如何将float数据转换为string，我就是这样，今天查了一下MSDN，才知道C提供了_gcvt函数实现这个功能，收获着实不小，为了方便自己查询，也为了那些像我这样的网友能够了解该函数的具体用法，我把MSDN的原文原封不动抄录如下：

_gcvt

Converts a floating-point value to a string, which it stores in a buffer.

char *_gcvt( double value, int digits, char *buffer );

For additional compatibility information, see Compatibility in the Introduction.

Libraries

Return Value

_gcvt returns a pointer to the string of digits. There is no error return.

Parameters

value

Value to be converted

digits

Number of significant digits stored

buffer

Storage location for result

Remarks

The _gcvt function converts a floating-point value to a character string (which includes a decimal point and a possible sign byte) and stores the string in buffer. The buffer should be large enough to accommodate the converted value plus a terminating null character, which is appended automatically. If a buffer size of digits + 1 is used, the function overwrites the end of the buffer. This is because the converted string includes a decimal point and can contain sign and exponent information. There is no provision for overflow. _gcvt attempts to produce digits digits in decimal format. If it cannot, it produces digits digits in exponential format. Trailing zeros may be suppressed in the conversion.

Example

/* _GCVT.C: This program converts -3.1415e5
 * to its string representation.
 */

#include <stdlib.h>
#include <stdio.h>

void main( void )
{
   char buffer[50];
   double source = -3.1415e5;
   _gcvt( source, 7, buffer );
   printf( "source: %f  buffer: '%s'/n", source, buffer );
   _gcvt( source, 7, buffer );
   printf( "source: %e  buffer: '%s'/n", source, buffer );
}

Output

source: -314150.000000  buffer: '-314150.'
source: -3.141500e+005  buffer: '-314150.'