MSBuild BuildInParallel，自定义任务生成进程无法运行

我使用 MSBuild 任务的 BuildInParallel 属性来并行运行生成项目。根项目正在构建四个子项目。子项目使用自定义 MSBuild 任务，该任务使用 System.Diagnostics.Process 启动新进程。由于某种原因，当 UseShellExecute 为 false 时，生成的进程无法正常运行。我不知道为什么会这样，也无法弄清楚错误是什么 - 所发生的只是 Process.ExitCode 为 1，无一例外。

这是自定义 MSBuild 任务：

using System;
using Microsoft.Build.Utilities;
using System.Diagnostics;

public class MSBuildProcessTask : Task
{
    public string Executable { get; set; }
    public string Arguments { get; set; }

    public override bool Execute()
    {
        using (var p = new Process())
        {
            try
            {
                p.StartInfo = new ProcessStartInfo(Executable, Arguments)
                                {
                                    UseShellExecute = false,
                                    //RedirectStandardOutput = true
                                };
                //p.OutputDataReceived += (o, e) =>
                //{
                //    if (e.Data != null)
                //    {
                //        Log.LogMessage(MessageImportance.Normal, e.Data);
                //    }
                //};
                p.Start();
                //p.BeginOutputReadLine();
                p.WaitForExit();
            }
            catch (Exception e)
            {
                throw; // for setting breakpoint
            }
            finally
            {
                if (p.ExitCode != 0)
                {
                    Log.LogError("Error.  Exit code: " + p.ExitCode);
                }
                p.Close();
            }
        }
        return true;
    }
}

这是根 MSBuild 项目文件（Test.proj，实际上我只在这里构建两个子项目，但仍然收到错误..）：

<?xml version="1.0" encoding="utf-8" ?>
<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
    <UsingTask TaskName="MSBuildProcessTask" AssemblyFile="C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\bin\Debug\MSBuildProcessTask.dll" />
    <Target Name="Default">
        <ItemGroup>
            <ProjectFiles Include="$(MSBuildProjectDirectory)\Test.1.proj" />
            <ProjectFiles Include="$(MSBuildProjectDirectory)\Test.2.proj" />
            <!--<ProjectFiles Include="$(MSBuildProjectDirectory)\Test.3.proj" />
            <ProjectFiles Include="$(MSBuildProjectDirectory)\Test.4.proj" />-->
        </ItemGroup>
            <MSBuild BuildInParallel="true" Projects="@(ProjectFiles)" />
    </Target>
</Project>

这是子项目文件 (Test.1.proj) 的示例：

<?xml version="1.0" encoding="utf-8" ?>
<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
    <UsingTask TaskName="MSBuildProcessTask" AssemblyFile="C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\bin\Debug\MSBuildProcessTask.dll" />
    <Target Name="Default">
        <Message Text="Hello" />
        <MSBuildProcessTask Executable="sqlcmd" Arguments="-S .\SQLEXPRESS -Q &quot;SELECT @@VERSION&quot;" />
    </Target>
</Project>

我的命令行是：C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe /m /nr:false C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.proj

这是一个示例输出：

C:\Users\Tom>C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe /m /nr:false C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildPr
ocessTask\Test.proj
Microsoft (R) Build Engine Version 4.0.30319.1
[Microsoft .NET Framework, Version 4.0.30319.235]
Copyright (C) Microsoft Corporation 2007. All rights reserved.

Build started 16/08/2011 22:22:06.
     1>Project "C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.proj" on node 1 (default targets).
     1>Project "C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.proj" (1) is building "C:\Users\Tom\Sandbox\reposito
       ry_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.1.proj" (2) on node 1 (default targets).
     2>Default:
         Hello
     1>Project "C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.proj" (1) is building "C:\Users\Tom\Sandbox\reposito
       ry_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.2.proj" (3) on node 2 (default targets).



------------------------------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------------------------------

Microsoft SQL Server 2008 (SP1) - 10.0.2531.0 (X64)
        Mar 29 2009 10:11:52
        Copyright (c) 1988-2008 Microsoft Corporation
        Express Edition (64-bit) on Windows NT 6.1 <X64> (Build 7601: Service Pack 1)


(1 rows affected)
     3>Default:
         Hello
     2>Done Building Project "C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.1.proj" (default targets).
     3>C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.2.proj(6,3): error : Error.  Exit code: 1
     3>Done Building Project "C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.2.proj" (default targets).
     1>Done Building Project "C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.proj" (default targets).

Build succeeded.

       "C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.proj" (default target) (1) ->
       "C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.2.proj" (default target) (3) ->
       (Default target) ->
         C:\Users\Tom\Sandbox\repository_trunk\MSBuildProcessTask\MSBuildProcessTask\Test.2.proj(6,3): error : Error.  Exit code: 1

    0 Warning(s)
    1 Error(s)

Time Elapsed 00:00:00.23

C:\Users\Tom>

正如您所看到的，我们仅从 SQLCMD 命令之一获取输出。

没有机会说出到底是什么导致了问题，您必须自己调查或至少提供有关错误的更多详细信息。

尝试跑步MSBuild指定诊断详细级别，它将在运行时转储非常详细的输出：

MsBuild.exe /v:diag