进一步完成报文打包接口,打包各功能模块的基本结构以搭建成型
设计思路：
	case fmt1:
		case en1:
			case ascii:
				buildASCII
			...
		case en2:
			...
	case fmt2:
		case en1:
			case ascii:
				buildASCII
			...
		case en2:
			...
1-完全实现了buildAscii函数