How to Run C# Code from PowerShell?

Some time back, I wrote C# code for SharePoint Administration Governance purpose: Find Large Lists & Generate Report in SharePoint , which actually scans all lists in all sites and creates a report in CSV format.

I feel PowerShell is more convenient than C# for couple of reasons:

• Because, PowerShell is quite powerful and more flexible administration and automation tool
• Although C# is good for typical Software development, for such small tasks C# project is overkill!
• Its faster to write, deploy and change it in PowerShell than creating a project in Visual Studio, compiling it, deploying it to the target, correcting the code, compiling it again, deploying it again!

So, I wanted to leverage the existing C# code. While the code is relatively simpler to rewrite in PowerShell, Found another interesting way to run C# code in PowerShell. Here is an example:

#Assemblies to Reference 
$Assembly = (
    "Microsoft.SharePoint, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" ,
    "Microsoft.SharePoint.Publishing, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c"
    );

# C# Source Code 
$SourceCode = @"
using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;
using System.IO;
 
namespace SPGovernance
{
    public class AdminReports
    {
        public static void GenerateLargeListsReport(string siteCollURL)
        {
         SPSite site = new SPSite(siteCollURL);
   StreamWriter SW;
   
   //Enumerate through each sub-site
            foreach (SPWeb web in site.AllWebs)
                {
                    foreach (SPList list in web.Lists)
                    {
                        if (list.ItemCount > 2000)
                        {
                            //Log the details to a file
                            SW = File.AppendText("c:\\LargeListsInfo.csv");
                            SW.WriteLine(list.Title + "," + web.Url  + list.DefaultViewUrl + "," + list.ItemCount);
                            SW.Close();
                        }
                    }                
   
             }
    Console.WriteLine("Large Lists Reports has been Generated!"); 
        }
    }
}
"@

#Add the Assembly
Add-Type -ReferencedAssemblies $Assembly -TypeDefinition $SourceCode -Language CSharp

#Call the function from Assembly
[SPGovernance.AdminReports]::GenerateLargeListsReport("http://sharepoint.crescent.com/sites/Sales") 

One limitation is: You may get "Add-Type : Cannot add type. The type name 'SPGovernance.AdminReports' already exists" error message if you try to execute the code more than once. This is a known limitation and you have to launch a new PowerShell window and execute the code.