A work in progress for a couple (maybe more) classes to wrap some `dotnet new` commands.

visual-studio-classes.ps1

<# e.g.:
. .\visual-studio-classes.ps1

$csproj = [Project]::CreateClassLib(".\Solution\ClassLib\ClassLib.csproj");
$csproj.AddClass('MyClass');
#>
class Project {
	[string]$Folder;

    Project() {
        $this.Init((Get-Location).Path, "csproj");
    }
    Project($folder) {
        $this.Init($folder, "csproj");
    }

    Project($folder, $projectType) {
        $this.Init($folder, $projectType);
    }

    [void] AddClass([string]$className) {
        $path = "$($this.Folder)\*.$($this.projectType)";
        Write-host "AddClass: $path";
        if (!(Test-Path -Path $path)){
            Write-Error "no project file exists in folder '$($this.Folder)'";
        } else {
            dotnet new class -n "$className" -o "$($this.Folder)";
        }
    }

    [void] AddInterface([string]$interfaceName) {
        if (!(Test-Path -Path "$($this.Folder)\*.$($this.projectType)")){
            Write-Error "no project file exists in folder '$($this.Folder)'";
        } else {
            Write-Host "dotnet new interface -n `"$interfaceName`" -o `"$($this.Folder)`"";
        }
    }

    [void] AddProjectReference([string]$path){
        dotnet add $this.Folder reference $path;
    }

    [void] AddProjectReference([Project]$project){
        dotnet add $this.Folder reference $project.Folder;
    }

    [void] AddPackageReference([string]$packageIdentifier){
        # dotnet add $this.Folder package $packageIdentifier;
    }

    static [Project] CreateClassLib([string]$path) {
        $extension = (split-path -path $path -extension).Substring(1);
        $dir = (split-path -path $path);
        $file = (split-path -path $path -LeafBase);

        if(!(Test-Path -Path $path)) {
            dotnet new classlib -n $file -o $dir --framework 'net8.0';
            if(Test-Path "$dir\Class1.cs") { Remove-Item "$dir\Class1.cs"; }
        }
        $p = [Project]::new($dir, $extension);
        return $p;
    }

    static [Project] CreateXunit([string]$path) {
        $extension = (split-path -path $path -extension).Substring(1);
        $dir = (split-path -path $path);
        $file = (split-path -path $path -LeafBase);

        if(!(Test-Path -Path $path)) {
            dotnet new xunit -n $file -o $dir --framework 'net8.0';
            if(Test-Path "$dir\UnitTest1.cs") { Remove-Item "$dir\UnitTest1.cs"; }
        }
        $p = [Project]::new((Split-Path -Path $path), $extension);
        return $p;
    }

    hidden [void] Init($folder, $projectType) {
        $this.Folder = $folder;
        $this.projectType = $projectType;
     }
    hidden [string]$projectType;
}

<# eg:
. .\visual-studio-classes.ps1

$sln = [Solution]::Create("Accounting");
$csproj = $s.NewClassLibraryProject("Accounting\BookKeeping\BookKeeping.csproj");
#> 
class Solution {
	[string]$Folder;

    Solution($path){
        $this.Folder = $path;
    }

    # dotnet new gitignore -o $solutionName >NUL 2>&1 || $(throw 'error creating .gitignore');
    # dotnet new buildprops -o "$solutionName" >NUL 2>&1 || $(throw 'error creating buildprops');

    # NewClassLibraryProject
    [Project] NewClassLibraryProject([string] $libraryName) {
        $project = [Project]::CreateClassLib((Join-Path -Path $this.Folder -ChildPath $libraryName));
        $this.AddProject($project);
        return $project;
    }

    # NewTestProject
    [Project] NewTestProject([string] $libraryName) {
        $project = [Project]::CreateXunit((Join-Path -Path $this.Folder -ChildPath $libraryName));
        $this.AddProject($project);
        return $project;
    }

    # AddProject

    [void] AddProject([Project] $project) {
        dotnet sln "$($this.Folder)" add "$($project.Folder)" >NUL 2>&1 || $(throw 'error adding to solution');
    }

    static [Solution] Create([string]$path) {
        $extension = split-path -path $path -Extension;
        $dir = (split-path -path $path);
        $filename = (split-path -path $path -Leaf);
        $file = (split-path -path $path -LeafBase);
        if(!($extension)) {
            $filename = "$filename.sln"
            $dir = $path;
        }
        $fullPath = "$dir\$filename";

        if(!(Test-Path -Path $fullPath -PathType Leaf)) {
            if(!($dir)) { $dir = '.'; }
            Write-Information "Should create $filename in directory $dir";
            dotnet new solution -o $dir -n $file
        } else {
            Write-Information "Using existing solution $fullPath";
        }

        return [Solution]::new($dir);
    }
}