我正在从一个字节的十六进制值转换为它的 ascii 表示,但是当我尝试打印出结果字符串时,由于某种原因,长度是错误的。
这是我生成的代码和输出:
#include <math.h>
#include <string.h>
unsigned char numDigits(unsigned char aNum)
{
unsigned char digits = 0x00;
while (aNum)
{
// printf("aNum: %d\n",aNum);
aNum /= 0x0a;
digits++;
}
if(digits == 0x00)
return 1; // aNum was 0 but we still need to send the ascii representation of 0 so set lengeth to 1
return digits;
}
string numToAscii(unsigned char aNum)
{
int len = numDigits(aNum);
printf("Num digits: %d\n", len);
string asciiNum = new char[len];
for(int i = 0; i < len; i++)
{
int nthPlace = (int)pow(10.0,(len-(i+1)));
int nthNum = aNum/nthPlace;
asciiNum[i] = nthNum+0x30;
printf("adding %c\n", asciiNum[i]);
aNum-=nthNum*nthPlace;
}
return asciiNum;
}
int main ()
{
unsigned char one = 0xfd;
unsigned char two = 0x64;
unsigned char three = 0x40;
unsigned char four = 0x0f;
unsigned char five = 0x01;
string cone = numToAscii(one);
string ctwo= numToAscii(two );
string cthree = numToAscii(three );
string cfour = numToAscii(four );
string cfive= numToAscii(five );
printf("Len: %d One: %s\n", cone.length(), cone.c_str());
printf("Len: %d two : %s\n", ctwo.length(), ctwo.c_str());
printf("Len: %d three : %s\n", cthree.length(), cthree.c_str() );
printf("Len: %d four : %s\n", cfour.length(), cfour.c_str() );
printf("Len: %d five : %s\n",cfive.length(), cfive.c_str());
return 0;
}
输出:
Num digits: 3
adding 2
adding 5
adding 3
Num digits: 3
adding 1
adding 0
adding 0
Num digits: 2
adding 6
adding 4
Num digits: 2
adding 1
adding 5
Num digits: 1
adding 1
Len: 5 One: 253�)
Len: 6 two : 100�i
Len: 3 three : 64�
Len: 3 four : 15�
Len: 2 five : 1�