是否可以列出构建文件中所有可用的构建目标？

Question

给出一个构建文件（.csproj或msbuild.xml或其他文件），我想运行一个msbuild命令，其中列出了所有可用的已定义目标。

该功能存在吗？

我知道我可以在构建文件上执行Xpath搜索或其他操作，但是找不到包含文件中定义的目标。

Answer 1

使用MSBuild 2.0 / 3.5：自定义任务

您可以这样编写自定义msbuild任务：

using System;
using System.Collections.Generic;
using Microsoft.Build.BuildEngine;
using Microsoft.Build.Framework;
using Microsoft.Build.Utilities;

namespace MSBuildTasks
{
  public class GetAllTargets : Task
  {
    [Required]
    public String ProjectFile { get; set; }

    [Output]
    public ITaskItem[] Targets { get; set; }

    public override bool Execute()
    {
      var project = new Project(BuildEngine as Engine);
      project.Load(ProjectFile);

      var taskItems = new List<ITaskItem>(project.Targets.Count);
      foreach (Target target in project.Targets)
      {
        var metadata = new Dictionary<string, string>
                        {
                          {"Condition", target.Condition},
                          {"Inputs", target.Inputs},
                          {"Outputs", target.Outputs},
                          {"DependsOnTargets", target.DependsOnTargets}
                        };
        taskItems.Add(new TaskItem(target.Name, metadata));
      }

      Targets = taskItems.ToArray();

      return true;
    }
  }
}    

您将这样使用：

<Target Name="TestGetAllTargets">
  <GetAllTargets ProjectFile="$(MSBuildProjectFile)">
    <Output ItemName="TargetItems" TaskParameter="Targets"/>
  </GetAllTargets>

  <Message Text="Name: %(TargetItems.Identity) Input: %(TargetItems.Input) --> Output: %(TargetItems.Output)"/>
</Target>

使用MSBuild 4.0：内联任务

使用MSBuild 4，您可以使用新的亮点：内联任务。内联任务允许您直接在msbuild文件中定义行为。

<UsingTask TaskName="GetAllTargets"
           TaskFactory="CodeTaskFactory"
           AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.v4.0.dll" >
  <ParameterGroup>
    <ProjectFile ParameterType="System.String" Required="true"/>
    <TargetsOut ParameterType="Microsoft.Build.Framework.ITaskItem[]" Output="true"/>
  </ParameterGroup>
  <Task>
    <Reference Include="System.Xml"/>
    <Reference Include="Microsoft.Build"/>
    <Reference Include="Microsoft.Build.Framework"/>
    <Using Namespace="Microsoft.Build.Evaluation"/>
    <Using Namespace="Microsoft.Build.Execution"/>
    <Using Namespace="Microsoft.Build.Utilities"/>
    <Using Namespace="Microsoft.Build.Framework"/>
    <Code Type="Fragment" Language="cs">
      <![CDATA[
        var project = new Project(ProjectFile);

        var taskItems = new List<ITaskItem>(project.Targets.Count);
        foreach (KeyValuePair<string, ProjectTargetInstance> kvp in project.Targets)
        {
          var target = kvp.Value;
          var metadata = new Dictionary<string, string>
                          {
                            {"Condition", target.Condition},
                            {"Inputs", target.Inputs},
                            {"Outputs", target.Outputs},
                            {"DependsOnTargets", target.DependsOnTargets}
                          };
          taskItems.Add(new TaskItem(kvp.Key, metadata));
        }

        TargetsOut = taskItems.ToArray();
      ]]>
    </Code>
  </Task>
</UsingTask>

<Target Name="Test">
  <GetAllTargets ProjectFile="$(MSBuildProjectFile)">
    <Output ItemName="TargetItems" TaskParameter="TargetsOut"/>  
  </GetAllTargets>

  <Message Text="%(TargetItems.Identity)"/>
</Target>

Answer 2

从Visual Studio 16.6预览版1开始，在MSBuild中实现。

示例用法：msbuild myProject.proj -targets

这应该与Visual Studio 16.6预览1一起使用（在将来的某个时候）。

（（来源：https://github.com/microsoft/msbuild/pull/5032#issuecomment-587901124）

文档：

-targets[:file]
                 Prints a list of available targets without executing the
                 actual build process. By default the output is written to
                 the console window. If the path to an output file
                 is provided that will be used instead.
                 (Short form: -ts)
                 Example:
                   -ts:out.txt