openssl的用法, 请见之前博文, 下面仅仅给出base64编解码的代码:
#include <iostream>
#include <openssl/evp.h>
#pragma comment(lib, "libeay32.lib") 
#pragma comment(lib, "ssleay32.lib")  // 可以注释掉
using namespace std;
// base64编码
int Base64Encode(const char *encoded, int encodedLength, char *decoded)
{    
	return EVP_EncodeBlock((unsigned char*)decoded, (const unsigned char*)encoded, encodedLength);
}
// base解码
int Base64Decode(const char *encoded, int encodedLength, char *decoded) 
{    
	return EVP_DecodeBlock((unsigned char*)decoded, (const unsigned char*)encoded, encodedLength);
}
int main()
{
	char test[] = "hello";
	char result[1000] = {0}; // 编码的结果
	cout << Base64Encode(test, strlen(test), result) << endl;
	cout << result << endl;
	char org[1000] = {0};    // 解码的结果
	cout << Base64Decode(result, strlen(result), org) << endl;
	cout << org << endl;
	return 0;
}结果为:
8
 aGVsbG8=
 6
 hello
  
经对比, 与其他工具产生的值是相同的, 小有成就感。