hextodec.c

将16进制转换成10进制的C语言源码 提供任意位数（包含小数点）的转换

/*
  Write a program to convert a Hexdecimal number into Decimal.
  The program is developed by QinKuangYu.
*/
#include <stdio.h>
void main()
{
int i,acceptflag,dotnum;
char c;
double floatpoint,dec;
printf("\n\nInput the Hexdecimal: ");
dotnum=0;
dec=0;
floatpoint=1;
while ((c=getch())!=13)
{      acceptflag=0;
       i=0;
       if ((c>='0')&&(c<='9')) { i=c-'0'; acceptflag=1; }
       if ((c=='.')&&(dotnum==0)) { dotnum++; acceptflag=1; }
       if ((c>='A')&&(c<='F')) { i=c-'A'+10; acceptflag=1; }
       if ((c>='a')&&(c<='f')) { i=c-'a'+10; acceptflag=1; }
       if (!acceptflag) { continue; }
       putchar(c);
       if (c=='.') {continue;}
       dec=dec*16+i;
       if (dotnum) floatpoint=floatpoint*16;
}
dec=dec/floatpoint;
printf("\nDecimal is %.15f",dec);
printf("\nPress any key to return..."); getch();
}