1.关于7z

7z是一种主流的 压缩格式，它拥有极高的压缩比。在计算机科学中，7z是一种可以使用多种压缩算法进行数据压缩的档案格式。主要有以下特点：

• 来源且模块化的组件结构
• 最高的压缩比
• 强大的AES-256加密
• 可更改配置的压缩算法
• 支持操大文件
• 支持多线程压缩
• 具有多种压缩文件格式
   

2.解压缩实现代码

实现对文件的解压缩方法是通过cmd命令，调用7z程式通过cmd命令实现对文件进行解压和压缩的操作，具体实现代码如下：

• 压缩代码

压缩的cmd命令："7Z a -tzip " + zipPath + "  " + filePath;

public ExecutionResult CompressFile(string filePath, string zipPath)//运行DOS命令
    {
      ExecutionResult exeRes = new ExecutionResult();
      exeRes.Status = true;
      try
      {
        Process process = new Process();
        process.StartInfo.FileName = "cmd.exe";
        string message = "";
        string command1 = "c:";
        string command2 = @"cd\";
        string command3 = @"cd C:\Progra~1\7-Zip";
        string command4 = "";


        command4 = "7Z a -tzip " + zipPath + " " + filePath;

        process.StartInfo.UseShellExecute = false;
        process.StartInfo.RedirectStandardInput = true;
        process.StartInfo.RedirectStandardOutput = true;
        process.StartInfo.RedirectStandardError = true;
        process.StartInfo.CreateNoWindow = true;
        process.Start();
        process.StandardInput.WriteLine(command1);
        process.StandardInput.WriteLine(command2);
        process.StandardInput.WriteLine(command3);
        process.StandardInput.WriteLine(command4);
        process.StandardInput.WriteLine("exit");
        message = process.StandardOutput.ReadToEnd(); //要等压缩完成后才可以来抓取这个压缩文件

        process.Close();
        if (!message.Contains("Everything is Ok"))
        {
          exeRes.Status = false;
          exeRes.Message = message;
        }
        else
        {
          exeRes.Anything = zipPath;
        }
      }
      catch (Exception ex)
      {
        exeRes.Message = ex.Message;
      }

      return exeRes;
    }

• 解压代码

解压的cmd命令："7Z x -tzip " + zipPath + " -o" + filePath + " -y";

public ExecutionResult DeCompressFile( string zipPath, string filePath)//运行DOS命令
    {
      ExecutionResult exeRes = new ExecutionResult();
      exeRes.Status = true;
      try
      {
        Process process = new Process();
        process.StartInfo.FileName = "cmd.exe";
        string message = "";
        string command1 = "c:";
        string command2 = @"cd\";
        string command3 = @"cd C:\Progra~1\7-Zip";
        string command4 = "";


        command4 = "7Z x -tzip " + zipPath + " -o" + filePath + " -y";

        process.StartInfo.UseShellExecute = false;
        process.StartInfo.RedirectStandardInput = true;
        process.StartInfo.RedirectStandardOutput = true;
        process.StartInfo.RedirectStandardError = true;
        process.StartInfo.CreateNoWindow = true;
        process.Start();
        process.StandardInput.WriteLine(command1);
        process.StandardInput.WriteLine(command2);
        process.StandardInput.WriteLine(command3);
        process.StandardInput.WriteLine(command4);
        process.StandardInput.WriteLine("exit");
        //process.WaitForExit();
        message = process.StandardOutput.ReadToEnd();//要等压缩完成后才可以来抓取这个压缩文件

        process.Close();
        if (!message.Contains("Everything is Ok"))
        {
          exeRes.Status = false;
          exeRes.Message = message;
        }
        else
        {
          exeRes.Anything = filePath;
        }
      }
      catch (Exception ex)
      {
        exeRes.Message = ex.Message;
      }

      return exeRes;
    }