一、关于Aquilia

因为之前遇到过一个问题：就是有一个二进制文件，要把它保存到一个只支持ASCII字符的文本文件中，并且要做到可恢复成与之前一模一样的二进制文件。今天正好有时间，就用VB.NET写了一个程序，取名叫Aquilia，用来实现这个功能。

这个程序的源码已经上传到GitAtOSC上，地址为：http://git.oschina.net/Tsybius2014/Aquilia_Transcoder

二、制作一个样本文件HelloWorld.exe

建立一个C#控制台应用程序，手动添加引用“System.Windows.Forms”，然后输入代码如下：

namespace HelloWorld
{
    class Program
    {
        static void Main(string[] args)
        {
            System.Windows.Forms.MessageBox.Show("Hello World!");
        }
    }
}

编译好的exe文件即为HelloWorld.exe，这个exe在运行后会弹出一个MessageBox上面写着“Hello World!”

三、Aquilia代码

1）ModuleMain.vb：主函数

Imports System.IO

Module ModuleMain

    ''' <summary>
    ''' 主函数
    ''' </summary>
    ''' <remarks></remarks>
    Sub Main()

        Dim Args As String() = System.Environment.GetCommandLineArgs()

        If Args.Count <> 4 Then
            PrintUsage()
            Pause()
            Exit Sub
        End If

        If (Args(1) <> "-e" And Args(1) <> "--encode" And _
             Args(1) <> "-d" And Args(1) <> "--decode") Then
            PrintUsage()
            Pause()
            Exit Sub
        End If

        If Not File.Exists(Args(2)) Then
            Console.WriteLine("文件：{0} 不存在",Args(2))
        End If

        If File.Exists(Args(3)) Then
            Console.Write("文件：{0} 已存在，要覆盖吗 (y/n)",Args(3))
            While True
                Dim temp As String = Console.ReadLine
                If temp = "Y" Or temp = "y" Then
                    Exit While
                ElseIf temp = "N" Or temp = "n" Then
                    Exit Sub
                Else
                    Console.Write("文件：{0} 已存在，要覆盖吗 (y/n)",Args(3))
                    Continue While
                End If
            End While
        End If

        If Args(1) = "-e" Or Args(1) = "--encode" Then
            FileConverHelper.Encode(Args(2),Args(3))
        ElseIf Args(1) = "-d" Or Args(1) = "--decode" Then
            FileConverHelper.Decode(Args(2),Args(3))
        End If

        Console.WriteLine("转换完毕！")
        Console.WriteLine("新生成的文件已被保存到： {0}",Args(3))

        Pause()

    End Sub

    ''' <summary>
    ''' 打印程序用法
    ''' </summary>
    ''' <remarks></remarks>
    Sub PrintUsage()

        Dim Usage(6) As String
        Usage(0) = "Aquilia程序使用方法"
        Usage(1) = "Aquilia [-e|--encode|-d|--decode] 文件1 文件2"
        Usage(2) = "第二个参数为-e或--encode时，Aquilia将文件1加密后写入到文件2中"
        Usage(3) = "第二个参数为-d或--decode时，Aquilia将文件1解密后写入到文件2中"
        Usage(4) = "示例参数1： -e HelloWorld.exe output.txt"
        Usage(5) = "示例参数2： -d output.txt HelloWorld2.exe"
        Console.WriteLine(Join(Usage,vbCrLf))

    End Sub

    ''' <summary>
    ''' 按任意键继续
    ''' </summary>
    ''' <remarks></remarks>
    Sub Pause()

        Console.WriteLine("按任意键继续")
        System.Console.ReadKey()
        System.Console.Write(Chr(8) + " ") '删除按下的“任意键”字符

    End Sub

End Module

2）FileConverHelper.vb：

Imports System.IO
Imports System.Text

Public Class FileConverHelper

    ''' <summary>
    ''' 将file1内容的以文本的形式输出到file2中
    ''' </summary>
    ''' <param name="file1"></param>
    ''' <param name="file2"></param>
    ''' <remarks></remarks>
    Public Shared Sub Encode(file1 As String,file2 As String)

        Dim fi As FileInfo = New FileInfo(file1)

        Dim fs1 As New FileStream(file1,FileMode.Open,FileAccess.Read,FileShare.Read)
        Dim buffer(fi.Length) As Byte
        fs1.Read(buffer,CInt(fi.Length))
        fs1.Close()

        Using sw As New StreamWriter(file2)
            For i As Integer = 0 To buffer.Length - 1
                If i <> buffer.Length - 1 Then
                    sw.Write(buffer(i) & ",")
                Else
                    sw.Write(buffer(i))
                End If
            Next
        End Using

        'Dim sb As New StringBuilder
        'For Each byt In buffer
        '    sb.Append(byt + ",")
        'Next

    End Sub

    ''' <summary>
    ''' 将file1文本以二进制的形式输出到file2中
    ''' </summary>
    ''' <param name="file1"></param>
    ''' <param name="file2"></param>
    ''' <remarks></remarks>
    Public Shared Sub Decode(file1 As String,file2 As String)

        Dim s() As String
        Using sr As New StreamReader(file1)
            s = sr.ReadToEnd().Split(",")
        End Using

        Dim buffer(s.Length - 1) As Byte
        For i As Integer = 0 To buffer.Length - 1
            buffer(i) = CInt(s(i))
        Next

        Dim fs2 As New FileStream(file2,FileMode.Create,FileAccess.Write,FileShare.None)
        fs2.Write(buffer,buffer.Length)
        fs2.Close()

    End Sub

End Class

四、运行结果

将HelloWorld.exe复制到Aquilia.exe同一个目录下，然后输入下面两条命令

Aquilia.exe -e HelloWorld.exe output.txt
Aquilia.exe -d output.txt HelloWorld2.exe

先将HelloWorld.exe转码后输出到output.txt下，再把output.txt中的内容重写到HelloWorld2.exe中

生成的output.txt内容如下：

重写成的HelloWorld2.exe，双击后，也会输出内容为“Hello World!”的MessageBox

附：VB程序集中的“启动选项→命令行参数”，保存在文件Aquilia.vbproj.user中（Aquilia为本程序集的名称）

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|Anycpu'">
    <StartArguments>-e HelloWorld.exe output.txt</StartArguments>
  </PropertyGroup>
</Project>

提交Git的时候不要忘了这个文件

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