程序代码：

double getNumber(char *data)
{
 double result = 0.0;
 int i;
 float j = 10;
 for (i = 0; data[i] != '.' && data[i] != '\0'; ++i)
     result += data[i] - '0' + 9 * result;
 for (i++; data[i] != '\0'; ++i, j *= 10)
     result += (data[i] - '0') / j;
 return result;
}