UE4 C++ Base64编解码
FString AUniqueID::Base64Encode(const unsigned char* Data, int DataByte){//编码表const char EncodeTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";//返回值FString strEncode;unsigned char Tmp[4] = {0 };for (int i = 0; i<(int)(DataByte / 3); i++){Tmp[1] = *Data++;Tmp[2] = *Data++;Tmp[3] = *Data++;strEncode += EncodeTable[Tmp[1] >> 2];strEncode += EncodeTable[((Tmp[1] << 4) | (Tmp[2] >> 4)) & 0x3F];strEncode += EncodeTable[((Tmp[2] << 2) | (Tmp[3] >> 6)) & 0x3F];strEncode += EncodeTable[Tmp[3] & 0x3F];}//对剩余数据进行编码int Mod = DataByte % 3;if (Mod == 1){Tmp[1] = *Data++;strEncode += EncodeTable[(Tmp[1] & 0xFC) >> 2];strEncode += EncodeTable[((Tmp[1] & 0x03) << 4)];strEncode += "==";}else if (Mod == 2){Tmp[1] = *Data++;Tmp[2] = *Data++;strEncode += EncodeTable[(Tmp[1] & 0xFC) >> 2];strEncode += EncodeTable[((Tmp[1] & 0x03) << 4) | ((Tmp[2] & 0xF0) >> 4)];strEncode += EncodeTable[((Tmp[2] & 0x0F) << 2)];strEncode += "=";}return strEncode;}void AUniqueID::Base64Decode(const char* Data, int DataByte, TArray<BYTE>& OutData){//解码表const char DecodeTable[] ={0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,62, // '+'0, 0, 0,63, // '/'52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // '0'-'9'0, 0, 0, 0, 0, 0, 0,0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // 'A'-'Z'0, 0, 0, 0, 0, 0,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // 'a'-'z'};//返回值int nValue;int i = 0;while (i < DataByte){if (*Data != '\r' && *Data != '\n'){nValue = DecodeTable[*Data++] << 18;nValue += DecodeTable[*Data++] << 12;OutData.Add((nValue & 0x00FF0000) >> 16);if (*Data != '='){nValue += DecodeTable[*Data++] << 6;OutData.Add((nValue & 0x0000FF00) >> 8);if (*Data != '='){nValue += DecodeTable[*Data++];OutData.Add(nValue & 0x000000FF);}}i += 4;}else// 回车换行,跳过{Data++;i++;}}}
