Parsing Visual Studio Solution files

How can I parse Visual Studio solution (SLN) files in .NET? I would like to write an app that merges multiple solutions into one while saving the relative build order.

Solution 1:

The .NET 4.0 version of the Microsoft.Build assembly contains a SolutionParser class in the Microsoft.Build.Construction namespace that parses Visual Studio solution files.

Unfortunately this class is internal, but I've wrapped some of that functionality in a class that uses reflection to get at some common properties you might find helpful.

public class Solution
{
    //internal class SolutionParser
    //Name: Microsoft.Build.Construction.SolutionParser
    //Assembly: Microsoft.Build, Version=4.0.0.0

    static readonly Type s_SolutionParser;
    static readonly PropertyInfo s_SolutionParser_solutionReader;
    static readonly MethodInfo s_SolutionParser_parseSolution;
    static readonly PropertyInfo s_SolutionParser_projects;

    static Solution()
    {
        s_SolutionParser = Type.GetType("Microsoft.Build.Construction.SolutionParser, Microsoft.Build, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a", false, false);
        if (s_SolutionParser != null)
        {
            s_SolutionParser_solutionReader = s_SolutionParser.GetProperty("SolutionReader", BindingFlags.NonPublic | BindingFlags.Instance);
            s_SolutionParser_projects = s_SolutionParser.GetProperty("Projects", BindingFlags.NonPublic | BindingFlags.Instance);
            s_SolutionParser_parseSolution = s_SolutionParser.GetMethod("ParseSolution", BindingFlags.NonPublic | BindingFlags.Instance);
        }
    }

    public List<SolutionProject> Projects { get; private set; }

    public Solution(string solutionFileName)
    {
        if (s_SolutionParser == null)
        {
            throw new InvalidOperationException("Can not find type 'Microsoft.Build.Construction.SolutionParser' are you missing a assembly reference to 'Microsoft.Build.dll'?");
        }
        var solutionParser = s_SolutionParser.GetConstructors(BindingFlags.Instance | BindingFlags.NonPublic).First().Invoke(null);
        using (var streamReader = new StreamReader(solutionFileName))
        {
            s_SolutionParser_solutionReader.SetValue(solutionParser, streamReader, null);
            s_SolutionParser_parseSolution.Invoke(solutionParser, null);
        }
        var projects = new List<SolutionProject>();
        var array = (Array)s_SolutionParser_projects.GetValue(solutionParser, null);
        for (int i = 0; i < array.Length; i++)
        {
            projects.Add(new SolutionProject(array.GetValue(i)));
        }
        this.Projects = projects;
    }
}

[DebuggerDisplay("{ProjectName}, {RelativePath}, {ProjectGuid}")]
public class SolutionProject
{
    static readonly Type s_ProjectInSolution;
    static readonly PropertyInfo s_ProjectInSolution_ProjectName;
    static readonly PropertyInfo s_ProjectInSolution_RelativePath;
    static readonly PropertyInfo s_ProjectInSolution_ProjectGuid;
    static readonly PropertyInfo s_ProjectInSolution_ProjectType;

    static SolutionProject()
    {
        s_ProjectInSolution = Type.GetType("Microsoft.Build.Construction.ProjectInSolution, Microsoft.Build, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a", false, false);
        if (s_ProjectInSolution != null)
        {
            s_ProjectInSolution_ProjectName = s_ProjectInSolution.GetProperty("ProjectName", BindingFlags.NonPublic | BindingFlags.Instance);
            s_ProjectInSolution_RelativePath = s_ProjectInSolution.GetProperty("RelativePath", BindingFlags.NonPublic | BindingFlags.Instance);
            s_ProjectInSolution_ProjectGuid = s_ProjectInSolution.GetProperty("ProjectGuid", BindingFlags.NonPublic | BindingFlags.Instance);
            s_ProjectInSolution_ProjectType = s_ProjectInSolution.GetProperty("ProjectType", BindingFlags.NonPublic | BindingFlags.Instance);
        }
    }

    public string ProjectName { get; private set; }
    public string RelativePath { get; private set; }
    public string ProjectGuid { get; private set; }
    public string ProjectType { get; private set; }

    public SolutionProject(object solutionProject)
    {
        this.ProjectName = s_ProjectInSolution_ProjectName.GetValue(solutionProject, null) as string;
        this.RelativePath = s_ProjectInSolution_RelativePath.GetValue(solutionProject, null) as string;
        this.ProjectGuid = s_ProjectInSolution_ProjectGuid.GetValue(solutionProject, null) as string;
        this.ProjectType = s_ProjectInSolution_ProjectType.GetValue(solutionProject, null).ToString();
    }
}

Note that you have to change your target framework to ".NET Framework 4" (not client profile) to be able to add the Microsoft.Build reference to your project.

Solution 2:

With Visual Studio 2015 there is now a publicly accessible SolutionFile class which can be used to parse solution files:

using Microsoft.Build.Construction;
var _solutionFile = SolutionFile.Parse(path);

This class is found in the Microsoft.Build.dll 14.0.0.0 assembly. In my case it was located at:

C:\Program Files (x86)\Reference Assemblies\Microsoft\MSBuild\v14.0\Microsoft.Build.dll

Thanks to Phil for pointing this out!