现在一字符串：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生成文件
using (FileStream fs = new FileStream(path, FileMode.OpenOrCreate))
{
byte[] buffer = Convert.FromBase64String(content);
fs.Write(buffer, 0, buffer.Length);
}//然后用Base64加密后，结果却是不一致的byte[] buffer = Encoding.GetEncoding(encodingName).GetBytes(content);
return Convert.ToBase64String(buffer);//直接用Base64解密生成的文件，结果也是不一样的
byte[] bytes = Convert.FromBase64String(content);
decode = Encoding.GetEncoding("utf-8").GetString(bytes);
新手在些求解，谢谢各位。
using (FileStream fs = new FileStream(path, FileMode.OpenOrCreate))
{
byte[] buffer = Convert.FromBase64String(content);
fs.Write(buffer, 0, buffer.Length);
}//然后用Base64加密后，结果却是不一致的byte[] buffer = Encoding.GetEncoding(encodingName).GetBytes(content);
return Convert.ToBase64String(buffer);//直接用Base64解密生成的文件，结果也是不一样的
byte[] bytes = Convert.FromBase64String(content);
decode = Encoding.GetEncoding("utf-8").GetString(bytes);
新手在些求解，谢谢各位。
2、尽量不要滥用名字。比如
Convert.FromBase64String(content);里面的content应该是Base64码。
而
Encoding.GetEncoding(encodingName).GetBytes(content);里面的content应该是原文。
在没有上下文情况下，很难理解你问的问题，不知道此content是否彼content...