C++ 10进制, 16进制, ASCII码, 单字节与多字节的相互转换

这些简单的转换是用的比较频繁的, 因此将这些功能全部封装在一个类中

头文件

 #pragma once
 #include <stdlib.h>
 #include <string>
 #include "tchar.h"
 #include "windows.h"
 using namespace std;
 enum TRANSFORM
 {
     SINGLECHAR, //单字节转换    eg:0x2121 => 33 33
     ALLCHAR,    //所有字节转换  eg:0x2121 => 8481
 };
 class Transform
 {
 public:
     Transform(void);
     ~Transform(void);

 public:
     string HexStrToAsciiStr(string strValue);
     string AsciiStrToHexStr(string strValue);
     string HexToDescInt(string strVaule, TRANSFORM);
     string DescIntToHex(string strValue);
     string TCharToString(TCHAR* TValue);
     void StringToTChar(string strValue, TCHAR* DestTchar);
 private:
     string strRepalce(string& strValue, string strSrc, string strDest);
 };

cpp文件

 #include "Transform.h"
 #pragma warning(disable:4996)

 Transform::Transform(void)
 {

 }

 Transform::~Transform(void)
 {

 }

 string Transform::HexStrToAsciiStr(string strValue)
 {
     string strTemp;
     if(strValue.find("0x") != string::npos || strValue.find("0X") != string::npos)
     {
         if(strValue.find("0x") != string::npos)
             strTemp = strRepalce(strValue, "0x", "");
         else
             strTemp = strRepalce(strValue, "0X", "");
     }
     if(strTemp.length() % != )
         strTemp.insert(, , '');
     string strRet;
     int temp = ;
     for(int i = ; i < strTemp.length(); i++)
     {
         int flag = (i %  == ) ?  : ;
         if(strTemp.c_str()[i] > '' && strTemp.c_str()[i] < '')
         {
             temp += (strTemp.c_str()[i] - '')*flag;
         }
         else if(strTemp.c_str()[i] == 'a' || strTemp.c_str()[i] == 'A')
         {
             temp += (*flag);
         }
         else if(strTemp.c_str()[i] == 'b' || strTemp.c_str()[i] == 'B')
         {
             temp += (*flag);
         }
         else if(strTemp.c_str()[i] == 'c' || strTemp.c_str()[i] == 'C')
         {
             temp += (*flag);
         }
         else if(strTemp.c_str()[i] == 'd' || strTemp.c_str()[i] == 'D')
         {
             temp += (*flag);
         }
         else if(strTemp.c_str()[i] == 'e' || strTemp.c_str()[i] == 'E')
         {
             temp += (*flag);
         }
         else if(strTemp.c_str()[i] == 'f' || strTemp.c_str()[i] == 'F')
         {
             temp += (*flag);
         }
         if(i %  != )
         {
             strRet+=temp;
             temp =;
         }
     }
     return strRet;
 }

 string Transform::AsciiStrToHexStr(string strValue)
 {
     if(strValue.length() == )
         return "";
     char Src[] = {  };
     strcpy_s(Src, strValue.c_str());
     int len = strValue.length();
     char* Dest = (char*)calloc(*len +, sizeof(char));
     for( int i = , j = ; i < strlen(strValue.c_str()); i++ )
     {
          char HiHalf = Src[i] >> ;
          char LoHalf = Src[i] & 0x0F;
          Dest[j++] = ( HiHalf <=  ) ? ( HiHalf + '' ) : ( HiHalf -  + 'A' );
          Dest[j++] = ( LoHalf <=  ) ? ( LoHalf + '' ) : ( LoHalf -  + 'A' );
     }
     string strRet = Dest;
     delete[] Dest;
     Dest = NULL;
     return strRet;
 }

 string Transform::HexToDescInt(string strVaule, TRANSFORM tfType)
 {
     if(strVaule.find("0x") != string::npos || strVaule.find("0X") != string::npos)
     {
         if(strVaule.find("0x") != string::npos)
             strVaule = strRepalce(strVaule, "0x", "");
         else
             strVaule = strRepalce(strVaule, "0X", "");
     }

     if(strVaule.length() %  != )
         strVaule.insert(, , '');
     if(strVaule.length() == )
         return "";
     string strRet;
     unsigned long iValue = ;
     switch(tfType)
     {
     case ALLCHAR:
         {
             for(int i = ; i < strVaule.length(); i++)
             {
                 iValue += (strVaule.c_str()[i] - '') << *(strVaule.length() - i -);
             }
             strRet = to_string(iValue);
         }break;
     case SINGLECHAR:
         {
             for(int i = ; i < strVaule.length(); i+=)
             {
                 iValue += (strVaule.c_str()[i] - '') << ;
                 if(strVaule.length() >= i+)
                 {
                     iValue += (strVaule.c_str()[i+] - '');
                 }
                 strRet += (to_string(iValue) + " ");
                 iValue = ;
             }
         }break;
     default:
         break;
     }
     return strRet;
 }

 string Transform::DescIntToHex(string strValue)
 {
     if(strValue.length() == )
         return "";
     if(strValue.length() %  != )
         strValue.insert(, , '');
     char temp[] = {  };
     int iValue = atoi(strValue.c_str());
     itoa(iValue, temp, );
     string strRet = "0x";
     strRet+= temp;
     return strRet;
 }

 string Transform::strRepalce(string& strValue, string strSrc, string strDest)
 {
     string::size_type pos = ;
     string::size_type srclen = strSrc.size();
     string::size_type dstlen = strDest.size();

     while( (pos=strValue.find(strSrc, pos)) != std::string::npos )
     {
         strValue.replace( pos, srclen, strDest );
         pos += dstlen;
     }
     return strValue;
 }

 string Transform::TCharToString(TCHAR* TValue)
 {
     string strRet;
     int iLength ;
     //获取字节长度
     iLength = WideCharToMultiByte(CP_ACP, , TValue, -, NULL, , NULL, NULL);
     //将tchar值赋给_char
     char* szChar = (char*)calloc(iLength, sizeof(char));
     WideCharToMultiByte(CP_ACP, , TValue, -, szChar, iLength, NULL, NULL);
     strRet = szChar;
     delete[] szChar;
     szChar = NULL;
     return strRet;
 }
 void Transform::StringToTChar(string strValue, TCHAR* DestTchar)
 {
     int iLength ;
     iLength = MultiByteToWideChar (CP_ACP, , strValue.c_str(), strlen (strValue.c_str()) + , NULL, );
     MultiByteToWideChar (CP_ACP, , strValue.c_str(), strlen (strValue.c_str()) + , DestTchar, iLength) ;
 }

测试文件

 #include<stdio.h>
 #include "Transform.h"

 int main()
 {
     Transform m_obj;
     string value= "3135353734414EmM";
     string Hex = m_obj.AsciiStrToHexStr(value);
     printf("Hex = %s \n", Hex.c_str());

     string asic = m_obj.HexStrToAsciiStr("0x303132343335363738394d5e6f20212223");
     printf("asci= %s\n", asic.c_str());

     string DecInt = m_obj.HexToDescInt("0x11122", ALLCHAR);
     printf("DesInt = %s \n", DecInt.c_str());
     DecInt = m_obj.HexToDescInt("0x11122", SINGLECHAR);
     printf("DesInt = %s \n", DecInt.c_str());

     string hex = m_obj.DescIntToHex("");
     printf("hex = %s\n", hex.c_str());

     string szChar = m_obj.TCharToString(_T("Hello World"));
     printf("szChar = %s\n", szChar.c_str());

     TCHAR tempChar[] ={  };
     m_obj.StringToTChar("Hello C++", tempChar);

     printf("tChar = %s\n", (char*)tempChar);
     getchar();
     return ;
 }

16进制字符串转10进制
调用系统函数pow(int x, int y)
x: 基数 y:指数

int HexToInt(string s)
{
        //STL 函数将字符串全部转大写
	transform(s.begin(), s.end(), s.begin(), ::toupper);
	int count = s.length();
	int sum = 0;
	for (auto it : s)
	{
                //A 的assic 为65.  it-55：表示A~F转10~15
		int flag = (it >= 65) ? (it - 55) : (it - 48);
		if (flag < 0 || flag > 15) continue;
		sum += flag *pow(16, --count);
	}
	printf("sum = %d\n", sum);
	return sum;
}

　　

PS: 代码写的有点low, 仅供参考 ~_~