C++ 中CString ANSI 与 utf-8转换 处理字符集编码

本文是参考 奔跑的艾斯 博主的资料整理的，以防自己忘掉
字符集编码时会遇到一些乱码问题，尤其是中文写入文件时是ANSI编码也就是在标准utf-8格式文件中是乱码，顾在写入文件时就对CString进行转码，然后写入文件就OK了。

//UTF8转ANSI
void UTF8toANSI(CString &strUTF8)
{
//获取转换为多字节后需要的缓冲区大小，创建多字节缓冲区
UINT nLen = MultiByteToWideChar(CP_UTF8,NULL,strUTF8,-1,NULL,NULL);
WCHAR *wszBuffer = new WCHAR[nLen+1];
nLen = MultiByteToWideChar(CP_UTF8,NULL,strUTF8,-1,wszBuffer,nLen);
wszBuffer[nLen] = 0;

nLen = WideCharToMultiByte(936,NULL,wszBuffer,-1,NULL,NULL,NULL,NULL);  
CHAR *szBuffer = new CHAR[nLen+1];  
nLen = WideCharToMultiByte(936,NULL,wszBuffer,-1,szBuffer,nLen,NULL,NULL);  
szBuffer[nLen] = 0;  
  
strUTF8 = szBuffer;  
//清理内存  
delete []szBuffer;  
delete []wszBuffer;  

}

//ANSI转UTF8
void ANSItoUTF8(CString &strAnsi)
{
//获取转换为宽字节后需要的缓冲区大小，创建宽字节缓冲区，936为简体中文GB2312代码页
UINT nLen = MultiByteToWideChar(936,NULL,strAnsi,-1,NULL,NULL);
WCHAR *wszBuffer = new WCHAR[nLen+1];
nLen = MultiByteToWideChar(936,NULL,strAnsi,-1,wszBuffer,nLen);
wszBuffer[nLen] = 0;
//获取转为UTF8多字节后需要的缓冲区大小，创建多字节缓冲区
nLen = WideCharToMultiByte(CP_UTF8,NULL,wszBuffer,-1,NULL,NULL,NULL,NULL);
CHAR *szBuffer = new CHAR[nLen+1];
nLen = WideCharToMultiByte(CP_UTF8,NULL,wszBuffer,-1,szBuffer,nLen,NULL,NULL);
szBuffer[nLen] = 0;

strAnsi = szBuffer;  
//内存清理  
delete []wszBuffer;  
delete []szBuffer;  

}