标签：arguments argument ati 根据 sync assert start exec hostname
很多时候我们可能会需要执行一段命令获取一个输出，遇到的比较典型的就是之前我们需要用 FFMpeg 实现视频的编码压缩水印等一系列操作，当时使用的是 FFMpegCore 这个类库，这个类库的实现原理是启动另外一个进程，启动 ffmpeg 并传递相应的处理参数，并根据进程输出获取处理进度
为了方便使用，实现了两个帮助类来方便的获取进程的输出，分别是 ProcessExecutor 和 CommandRunner，前者更为灵活，可以通过事件添加自己的额外事件订阅处理，后者为简化版，主要是只获取输出的场景，两者的实现原理大体是一样的，启动一个 Process，并监听其输出事件获取输出
ProcessExecutor使用示例，这个示例是获取保存 nuget 包的路径的一个示例：
using var executor = new ProcessExecutor("dotnet", "nuget locals global-packages -l");
var folder = string.Empty;
executor.OnOutputDataReceived += (sender, str) =>
{
if(str is null)
return;
Console.WriteLine(str);
if(str.StartsWith("global-packages:"))
{
folder = str.Substring("global-packages:".Length).Trim();
}
};
executor.Execute();
Console.WriteLine(folder);
ProcessExecutor 实现代码如下：
public class ProcessExecutor : IDisposable
{
public event EventHandler<int> OnExited;
public event EventHandler<string> OnOutputDataReceived;
public event EventHandler<string> OnErrorDataReceived;
protected readonly Process _process;
protected bool _started;
public ProcessExecutor(string exePath) : this(new ProcessStartInfo(exePath))
{
}
public ProcessExecutor(string exePath, string arguments) : this(new ProcessStartInfo(exePath, arguments))
{
}
public ProcessExecutor(ProcessStartInfo startInfo)
{
_process = new Process()
{
StartInfo = startInfo,
EnableRaisingEvents = true,
};
_process.StartInfo.UseShellExecute = false;
_process.StartInfo.CreateNoWindow = true;
_process.StartInfo.RedirectStandardOutput = true;
_process.StartInfo.RedirectStandardInput = true;
_process.StartInfo.RedirectStandardError = true;
}
protected virtual void InitializeEvents()
{
_process.OutputDataReceived += (sender, args) =>
{
if (args.Data != null)
{
OnOutputDataReceived?.Invoke(sender, args.Data);
}
};
_process.ErrorDataReceived += (sender, args) =>
{
if (args.Data != null)
{
OnErrorDataReceived?.Invoke(sender, args.Data);
}
};
_process.Exited += (sender, args) =>
{
if (sender is Process process)
{
OnExited?.Invoke(sender, process.ExitCode);
}
else
{
OnExited?.Invoke(sender, _process.ExitCode);
}
};
}
protected virtual void Start()
{
if (_started)
{
return;
}
_started = true;
_process.Start();
_process.BeginOutputReadLine();
_process.BeginErrorReadLine();
_process.WaitForExit();
}
public async virtual Task SendInput(string input)
{
try
{
await _process.StandardInput.WriteAsync(input!);
}
catch (Exception e)
{
OnErrorDataReceived?.Invoke(_process, e.ToString());
}
}
public virtual int Execute()
{
InitializeEvents();
Start();
return _process.ExitCode;
}
public virtual async Task<int> ExecuteAsync()
{
InitializeEvents();
return await Task.Run(() =>
{
Start();
return _process.ExitCode;
}).ConfigureAwait(false);
}
public virtual void Dispose()
{
_process.Dispose();
OnExited = null;
OnOutputDataReceived = null;
OnErrorDataReceived = null;
}
}
CommandExecutor上面的这种方式比较灵活但有些繁琐，于是有了下面这个版本
使用示例：
[Fact]
public void HostNameTest()
{
if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
return;
}
var result = CommandRunner.ExecuteAndCapture("hostname");
var hostName = Dns.GetHostName();
Assert.Equal(hostName, result.StandardOut.TrimEnd());
Assert.Equal(0, result.ExitCode);
}
实现源码：
public static class CommandRunner
{
public static int Execute(string commandPath, string arguments = null, string workingDirectory = null)
{
using var process = new Process()
{
StartInfo = new ProcessStartInfo(commandPath, arguments ?? string.Empty)
{
UseShellExecute = false,
CreateNoWindow = true,
WorkingDirectory = workingDirectory ?? Environment.CurrentDirectory
}
};
process.Start();
process.WaitForExit();
return process.ExitCode;
}
public static CommandResult ExecuteAndCapture(string commandPath, string arguments = null, string workingDirectory = null)
{
using var process = new Process()
{
StartInfo = new ProcessStartInfo(commandPath, arguments ?? string.Empty)
{
UseShellExecute = false,
CreateNoWindow = true,
RedirectStandardOutput = true,
RedirectStandardError = true,
WorkingDirectory = workingDirectory ?? Environment.CurrentDirectory
}
};
process.Start();
var standardOut = process.StandardOutput.ReadToEnd();
var standardError = process.StandardError.ReadToEnd();
process.WaitForExit();
return new CommandResult(process.ExitCode, standardOut, standardError);
}
}
public sealed class CommandResult
{
public CommandResult(int exitCode, string standardOut, string standardError)
{
ExitCode = exitCode;
StandardOut = standardOut;
StandardError = standardError;
}
public string StandardOut { get; }
public string StandardError { get; }
public int ExitCode { get; }
}
如果只要执行命令获取是否执行成功则使用 CommandRunner.Execute 即可，只获取输出和是否成功可以用 CommandRunner.ExecuteAndCapture 方法，如果想要进一步的添加事件订阅则使用 ProcessExecutor
标签：arguments argument ati 根据 sync assert start exec hostname
原文地址：https://www.cnblogs.com/weihanli/p/13534390.html
