C/C++ double 转 字符串string (char 数组)

之前用double转string 均采用非基础库，但是仔细一想，基础库也并非不能实现，种种原因驱使之下，之下代码诞生，不可能有人看不懂！

必须要批判一下CSDN上面，double转字符串 都还要上传并且消耗积分下载的人，真的抽象

#include "stdio.h"
//获取字符串长度
int strlen(char * ret)
{
	int i = 0;
	while (true)
	{
		if (*(ret + i) == '\0')
		{
			break;
		}
		else
		{
			i += 1;
		}
	}
	return i;
}

void doubletochar(char *strdouble,double result)
{
	//char strdouble[99];
	double ret = result;
	int zheng = (int)result, zweishu = 0, wei = 10, xweishu = 0;
	while (true)
	{
		int yushu = zheng % wei;
		if (yushu == zheng)
		{
			zweishu++;
			break;
		}
		else
		{
			zweishu++;
			wei = wei * 10;
		}
	}
	for (int i = 0; i < zweishu; i++)
	{
		int yushu = zheng % 10;
		zheng = zheng / 10;
		strdouble[zweishu - i - 1] = yushu + '0';
	}
	strdouble[zweishu] = '.';
	while (true)
	{
		if ((int)ret != ret)
		{
			ret = ret * 10;
			xweishu++;
		}
		else
			break;
	}
	for (int i = 0; i < xweishu; i++)
	{
		int yushu = (int)ret % 10;
		ret = ret / 10;
		strdouble[zweishu + xweishu - i] = yushu + '0';
	}
	strdouble[zweishu + xweishu + 1] = '\0';
	for (int i = 0; i < strlen(strdouble); i++)
	{
		//putchar(strdouble[i]);
	}
}


int main()
{
	char demo[99];
	doubletochar(demo, 18.369);
	printf("%s", demo);
	while (true);
}