如何：在 C# 中执行命令行，获取 STD OUT 结果

Question

如何从 C# 执行命令行程序并取回 STD OUT 结果？具体来说，我想对以编程方式选择的两个文件执行 DIFF，并将结果写入文本框。

Answer 1

// Start the child process.
 Process p = new Process();
 // Redirect the output stream of the child process.
 p.StartInfo.UseShellExecute = false;
 p.StartInfo.RedirectStandardOutput = true;
 p.StartInfo.FileName = "YOURBATCHFILE.bat";
 p.Start();
 // Do not wait for the child process to exit before
 // reading to the end of its redirected stream.
 // p.WaitForExit();
 // Read the output stream first and then wait.
 string output = p.StandardOutput.ReadToEnd();
 p.WaitForExit();

代码来自MSDN。

Answer 2

这是一个简单的示例：

//Create process
System.Diagnostics.Process pProcess = new System.Diagnostics.Process();

//strCommand is path and file name of command to run
pProcess.StartInfo.FileName = strCommand;

//strCommandParameters are parameters to pass to program
pProcess.StartInfo.Arguments = strCommandParameters;

pProcess.StartInfo.UseShellExecute = false;

//Set output of program to be written to process output stream
pProcess.StartInfo.RedirectStandardOutput = true;   

//Optional
pProcess.StartInfo.WorkingDirectory = strWorkingDirectory;

//Start the process
pProcess.Start();

//Get program output
string strOutput = pProcess.StandardOutput.ReadToEnd();

//Wait for process to finish
pProcess.WaitForExit();

Answer 3

我发现另一个有用的参数，我用它来消除进程窗口

pProcess.StartInfo.CreateNoWindow = true;

如果这是您想要的，这有助于完全隐藏用户的黑色控制台窗口。

Answer 4

// usage
const string ToolFileName = "example.exe";
string output = RunExternalExe(ToolFileName);

public string RunExternalExe(string filename, string arguments = null)
{
    var process = new Process();

    process.StartInfo.FileName = filename;
    if (!string.IsNullOrEmpty(arguments))
    {
        process.StartInfo.Arguments = arguments;
    }

    process.StartInfo.CreateNoWindow = true;
    process.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
    process.StartInfo.UseShellExecute = false;

    process.StartInfo.RedirectStandardError = true;
    process.StartInfo.RedirectStandardOutput = true;
    var stdOutput = new StringBuilder();
    process.OutputDataReceived += (sender, args) => stdOutput.AppendLine(args.Data); // Use AppendLine rather than Append since args.Data is one line of output, not including the newline character.

    string stdError = null;
    try
    {
        process.Start();
        process.BeginOutputReadLine();
        stdError = process.StandardError.ReadToEnd();
        process.WaitForExit();
    }
    catch (Exception e)
    {
        throw new Exception("OS error while executing " + Format(filename, arguments)+ ": " + e.Message, e);
    }

    if (process.ExitCode == 0)
    {
        return stdOutput.ToString();
    }
    else
    {
        var message = new StringBuilder();

        if (!string.IsNullOrEmpty(stdError))
        {
            message.AppendLine(stdError);
        }

        if (stdOutput.Length != 0)
        {
            message.AppendLine("Std output:");
            message.AppendLine(stdOutput.ToString());
        }

        throw new Exception(Format(filename, arguments) + " finished with exit code = " + process.ExitCode + ": " + message);
    }
}

private string Format(string filename, string arguments)
{
    return "'" + filename + 
        ((string.IsNullOrEmpty(arguments)) ? string.Empty : " " + arguments) +
        "'";
}

Answer 5

此页面上接受的答案有一个弱点，在极少数情况下会很麻烦。按照惯例，程序写入的文件句柄有两个，stdout 和 stderr。 如果您只是读取单个文件句柄，例如来自 Ray 的答案，并且您正在启动的程序将足够的输出写入 stderr，它将填满输出 stderr 缓冲区并阻塞。然后你的两个进程就死锁了。缓冲区大小可以是 4K。 这在短期程序中极为罕见，但如果您有一个长期运行的程序反复输出到 stderr，它最终会发生。这很难调试和跟踪。

有几个很好的方法可以解决这个问题。

1. 一种方法是执行 cmd.exe 而不是您的程序，并使用 cmd.exe 的 /c 参数来调用您的程序以及 cmd.exe 的“2>&1”参数来告诉它合并 stdout 和 stderr .

           var p = new Process();
           p.StartInfo.FileName = "cmd.exe";
           p.StartInfo.Arguments = "/c mycmd.exe 2>&1";
   

2. 另一种方法是使用同时读取两个句柄的编程模型。

           var p = new Process();
           p.StartInfo.FileName = "cmd.exe";
           p.StartInfo.Arguments = @"/c dir \windows";
           p.StartInfo.CreateNoWindow = true;
           p.StartInfo.RedirectStandardError = true;
           p.StartInfo.RedirectStandardOutput = true;
           p.StartInfo.RedirectStandardInput = false;
           p.OutputDataReceived += (a, b) => Console.WriteLine(b.Data);
           p.ErrorDataReceived += (a, b) => Console.WriteLine(b.Data);
           p.Start();
           p.BeginErrorReadLine();
           p.BeginOutputReadLine();
           p.WaitForExit();
   

Answer 6

 System.Diagnostics.ProcessStartInfo psi =
   new System.Diagnostics.ProcessStartInfo(@"program_to_call.exe");
 psi.RedirectStandardOutput = true;
 psi.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
 psi.UseShellExecute = false;
 System.Diagnostics.Process proc = System.Diagnostics.Process.Start(psi); ////
 System.IO.StreamReader myOutput = proc.StandardOutput;
 proc.WaitForExit(2000);
 if (proc.HasExited)
  {
      string output = myOutput.ReadToEnd();
 }

Answer 7

如果您不介意引入依赖项，CliWrap 可以为您简化：

using CliWrap;
using CliWrap.Buffered;

var result = await Cli.Wrap("target.exe")
   .WithArguments("arguments")
   .ExecuteBufferedAsync();

var stdout = result.StandardOutput;

Answer 8

您需要使用ProcessStartInfo 并启用RedirectStandardOutput - 然后您可以读取输出流。您可能会发现使用“>”将输出重定向到文件（通过操作系统）更容易，然后只需读取文件。

[编辑：就像雷所做的那样：+1]

Answer 9

单行运行命令：

new Process() { StartInfo = new ProcessStartInfo("echo", "Hello, World") }.Start();

以最短的可重复代码读取命令输出：

    var cliProcess = new Process() {
        StartInfo = new ProcessStartInfo("echo", "Hello, World") {
            UseShellExecute = false,
            RedirectStandardOutput = true
        }
    };
    cliProcess.Start();
    string cliOut = cliProcess.StandardOutput.ReadToEnd();
    cliProcess.WaitForExit();
    cliProcess.Close();

Answer 10

您可以使用 Process 类启动任何命令行程序，并使用您创建的流读取器（基于字符串或内存位置）设置 Process 实例的 StandardOutput 属性。该过程完成后，您可以在该流上执行所需的任何差异。

Answer 11

如果您尝试查询 PC/服务器上的本地 ARP 缓存，这可能对某人有用。

List<string[]> results = new List<string[]>();

        using (Process p = new Process())
        {
            p.StartInfo.CreateNoWindow = true;
            p.StartInfo.RedirectStandardOutput = true;
            p.StartInfo.UseShellExecute = false;
            p.StartInfo.Arguments = "/c arp -a";
            p.StartInfo.FileName = @"C:\Windows\System32\cmd.exe";
            p.Start();

            string line;

            while ((line = p.StandardOutput.ReadLine()) != null)
            {
                if (line != "" && !line.Contains("Interface") && !line.Contains("Physical Address"))
                {
                    var lineArr = line.Trim().Split(' ').Select(n => n).Where(n => !string.IsNullOrEmpty(n)).ToArray();
                    var arrResult = new string[]
                {
                   lineArr[0],
                   lineArr[1],
                   lineArr[2]
                };
                    results.Add(arrResult);
                }
            }

            p.WaitForExit();
        }

Answer 12

如果您还需要在 cmd.exe 中执行某些命令，您可以执行以下操作：

// Start the child process.
Process p = new Process();
// Redirect the output stream of the child process.
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "cmd.exe";
p.StartInfo.Arguments = "/C vol";
p.Start();
// Read the output stream first and then wait.
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();
Console.WriteLine(output);

这仅返回命令本身的输出：

您也可以使用StandardInput 代替StartInfo.Arguments：

// Start the child process.
Process p = new Process();
// Redirect the output stream of the child process.
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardInput = true;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "cmd.exe";
p.Start();
// Read the output stream first and then wait.
p.StandardInput.WriteLine("vol");
p.StandardInput.WriteLine("exit");
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();
Console.WriteLine(output);

结果如下：

Answer 13

由于这里的大多数答案都没有为IDisposable 实现using statemant 以及我认为可能需要的其他一些东西，所以我会添加这个答案。

对于 C# 8.0

// Start a process with the filename or path with filename e.g. "cmd". Please note the 
//using statemant
using myProcess.StartInfo.FileName = "cmd";
// add the arguments - Note add "/c" if you want to carry out tge  argument in cmd and  
// terminate
myProcess.StartInfo.Arguments = "/c dir";
// Allows to raise events
myProcess.EnableRaisingEvents = true;
//hosted by the application itself to not open a black cmd window
myProcess.StartInfo.UseShellExecute = false;
myProcess.StartInfo.CreateNoWindow = true;
// Eventhander for data
myProcess.Exited += OnOutputDataRecived;
// Eventhandler for error
myProcess.ErrorDataReceived += OnErrorDataReceived;
// Eventhandler wich fires when exited
myProcess.Exited += OnExited;
// Starts the process
myProcess.Start();
//read the output before you wait for exit
myProcess.BeginOutputReadLine();
// wait for the finish - this will block (leave this out if you dont want to wait for 
// it, so it runs without blocking)
process.WaitForExit();

// Handle the dataevent
private void OnOutputDataRecived(object sender, DataReceivedEventArgs e)
{
    //do something with your data
    Trace.WriteLine(e.Data);
}

//Handle the error
private void OnErrorDataReceived(object sender, DataReceivedEventArgs e)
{        
    Trace.WriteLine(e.Data);
    //do something with your exception
    throw new Exception();
}    

// Handle Exited event and display process information.
private void OnExited(object sender, System.EventArgs e)
{
     Trace.WriteLine("Process exited");
}

Answer 14

这可能不是最好/最简单的方法，但可能是一种选择：

从代码执行时，添加“ > output.txt”，然后读入 output.txt 文件。

Answer 15

PublicDomain 开源代码中有一个 ProcessHelper 类，您可能会感兴趣。

Answer 16

Julian 的解决方案已经过测试，并进行了一些小的修正。以下是同样使用https://sourceforge.net/projects/bat-to-exe/GenericConsole.cs 和https://www.codeproject.com/Articles/19225/Bat-file-compilerprogram.txt 作为args 部分的示例：

using System;
using System.Text;  //StringBuilder
using System.Diagnostics;
using System.IO;


class Program
{
    private static bool redirectStandardOutput = true;

    private static string buildargument(string[] args)
    {
        StringBuilder arg = new StringBuilder();
        for (int i = 0; i < args.Length; i++)
        {
            arg.Append("\"" + args[i] + "\" ");
        }

        return arg.ToString();
    }

    static void Main(string[] args)
    {
        Process prc = new Process();
        prc.StartInfo = //new ProcessStartInfo("cmd.exe", String.Format("/c \"\"{0}\" {1}", Path.Combine(Environment.CurrentDirectory, "mapTargetIDToTargetNameA3.bat"), buildargument(args)));
        //new ProcessStartInfo(Path.Combine(Environment.CurrentDirectory, "mapTargetIDToTargetNameA3.bat"), buildargument(args));
        new ProcessStartInfo("mapTargetIDToTargetNameA3.bat");
        prc.StartInfo.Arguments = buildargument(args);

        prc.EnableRaisingEvents = true;

        if (redirectStandardOutput == true)
        {
            prc.StartInfo.UseShellExecute = false;
        }
        else
        {
            prc.StartInfo.UseShellExecute = true;
        }

        prc.StartInfo.CreateNoWindow = true;

        prc.OutputDataReceived += OnOutputDataRecived;
        prc.ErrorDataReceived += OnErrorDataReceived;
        //prc.Exited += OnExited;

        prc.StartInfo.RedirectStandardOutput = redirectStandardOutput;
        prc.StartInfo.RedirectStandardError = redirectStandardOutput;

        try
        {
            prc.Start();
            prc.BeginOutputReadLine();
            prc.BeginErrorReadLine();
            prc.WaitForExit();
        }
        catch (Exception e)
        {
            Console.WriteLine("OS error: " + e.Message);
        }

        prc.Close();
    }

    // Handle the dataevent
    private static void OnOutputDataRecived(object sender, DataReceivedEventArgs e)
    {
        //do something with your data
        Console.WriteLine(e.Data);
    }

    //Handle the error
    private static void OnErrorDataReceived(object sender, DataReceivedEventArgs e)
    {
        Console.WriteLine(e.Data);
    }

    // Handle Exited event and display process information.
    //private static void OnExited(object sender, System.EventArgs e)
    //{
    //    var process = sender as Process;
    //    if (process != null)
    //    {
    //        Console.WriteLine("ExitCode: " + process.ExitCode);
    //    }
    //    else
    //    {
    //        Console.WriteLine("Process exited");
    //    }
    //}
}

代码需要在 VS2007 中编译，使用命令行 csc.exe 生成的可执行文件将无法正确显示控制台输出，甚至会因 CLR20r3 错误而崩溃。注释掉OnExited事件进程，bat到exe的console输出会更像原来的bat控制台输出。

Answer 17

这是一个小例子：

using System;
using System.Diagnostics;

class Program
{
    static void Main(string[] args)
    {
        var p = Process.Start(
            new ProcessStartInfo("git", "branch --show-current")
            {
                CreateNoWindow = true,
                UseShellExecute = false,
                RedirectStandardError = true,
                RedirectStandardOutput = true,
                WorkingDirectory = Environment.CurrentDirectory
            }
        );

        p.WaitForExit();
        string branchName =p.StandardOutput.ReadToEnd().TrimEnd();
        string errorInfoIfAny =p.StandardError.ReadToEnd().TrimEnd();

        if (errorInfoIfAny.Length != 0)
        {
            Console.WriteLine($"error: {errorInfoIfAny}");
        }
        else { 
            Console.WriteLine($"branch: {branchName}");
        }

    }
}

我相信这是最短的形式。

请注意，大多数命令行工具很容易混淆标准输出和标准错误，有时只需将它们组合成一个字符串就有意义。

p.ExitCode 有时也可能有用。

Answer 18

只是为了好玩，这是我获得 PYTHON 输出的完整解决方案 - 在按钮单击下 - 带有错误报告。只需添加一个名为“butPython”的按钮和一个名为“llHello”的标签...

    private void butPython(object sender, EventArgs e)
    {
        llHello.Text = "Calling Python...";
        this.Refresh();
        Tuple<String,String> python = GoPython(@"C:\Users\BLAH\Desktop\Code\Python\BLAH.py");
        llHello.Text = python.Item1; // Show result.
        if (python.Item2.Length > 0) MessageBox.Show("Sorry, there was an error:" + Environment.NewLine + python.Item2);
    }

    public Tuple<String,String> GoPython(string pythonFile, string moreArgs = "")
    {
        ProcessStartInfo PSI = new ProcessStartInfo();
        PSI.FileName = "py.exe";
        PSI.Arguments = string.Format("\"{0}\" {1}", pythonFile, moreArgs);
        PSI.CreateNoWindow = true;
        PSI.UseShellExecute = false;
        PSI.RedirectStandardError = true;
        PSI.RedirectStandardOutput = true;
        using (Process process = Process.Start(PSI))
            using (StreamReader reader = process.StandardOutput)
            {
                string stderr = process.StandardError.ReadToEnd(); // Error(s)!!
                string result = reader.ReadToEnd(); // What we want.
                return new Tuple<String,String> (result,stderr); 
            }
    }