This can also be done a line at a time in the PowerShell command line REPL (Read Eval Print Loop). Meaning, you can create different arrays and multidimensional arrays at the command line and then type and call the Excel functions.

Plus, these are only 4 of the many Excel functions available.

If you want to find out the other Excel math functions available, type this line at the command line (run the first three lines of code up to the WorksheetFunction first):

$wf | Get-Member -MemberType method | Out-GridView

# Calling Excel Math Functions From PowerShell            

$xl        = New-Object -ComObject Excel.Application
$xlprocess = Get-Process excel            

$wf   = $xl.WorksheetFunction
$data = 1,2,3,4
$m    = ((1,2,3),(4,5,6),(7,8,9))            

Write-Host -ForegroundColor green Median
$wf.Median($data)            

Write-Host -ForegroundColor green StDev
$wf.StDev($data)            

Write-Host -ForegroundColor green Var
$wf.Var($data)            

Write-Host -ForegroundColor green MInverse
$wf.MInverse($m)            

$xl.quit()
$xlprocess | kill

# Results
Median
2.5
StDev
1.29099444873581
Var
1.66666666666667
MInverse
-4.5035996273705E+15
9.00719925474099E+15
-4.5035996273705E+15
9.007199254741E+15
-1.8014398509482E+16
9.00719925474099E+15
-4.5035996273705E+15
9.00719925474099E+15
-4.5035996273705E+15

Grab the Code

I put the code up on my GitHub PowerShell Repository.

PowerShell inside Visual Studio 2010

That’s right, PowerShell inside Visual Studio 2010. Interesting possibilities. He also demoed (code that won’t will be shipped) where he worked Visual Studio like a puppet on strings from the PowerShell console. Again, interesting possibilities.

NuPack is a free, open source developer focused package management system for the .NET platform. I’ve blogged on NuPack and Power Console. PowerConsole has been re-released as part of NuPack.

• Check Available .NET Packages without NuPack Installed
• NuPack – Open Source Package Manager for .NET – Includes a PowerShell Interface
• Visual Visual Studio Keymaps using PowerShell
• Accessing Visual Studio’s Automation API From PowerShell
• PowerShell and F# Consoles in Visual Studio 2010
• PowerConsole – PowerShell Integrated with Visual Studio 2010

In PowerShell Version 1 that cmdlet is not available so you need to use the one of the Load* static methods found in System.Reflection.Assembly.

Why?

For example, in PowerShell, if you want to encode a Url you can use the UrlEncode method found in the .NET HttpUtility Class.

If you fire up PowerShell and try to call the static method UrlEncode found in System.Web.HttpUtility you’ll get this error.

[System.Web.HttpUtility]::UrlEncode("this is a test")

Unable to find type [System.Web.HttpUtility]: make sure that the assembly containing this type is loaded.

You can solve this by loading the System.Web .NET assembly. This is equivalent to being in the Visual Studio IDE, adding a reference and then adding a using statement.

Using Reflection.Assembly in PowerShell Version 1

[Reflection.Assembly]::LoadFile( `
  'C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Web.dll')`
  | out-null            
              
[System.Web.HttpUtility]::UrlEncode("this is a test")

Using Add-Type in PowerShell Version 2

Add-Type -AssemblyName System.Web            
[System.Web.HttpUtility]::UrlEncode("this is a test")

Additional Reflection.Assembly usage

[void] [Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms")
[reflection.assembly]::Load("mscorlib.dll") | Out-Null
[void][system.reflection.assembly]::loadfrom("c:\windows\system32\inetsrv\microsoft.web.administration.dll")

Additional Add-Type usage

Add-Type -AssemblyName "System.Windows.Forms"
Add-Type -AssemblyName "mscorlib.dll"
Add-Type -Path "c:\windows\system32\inetsrv\microsoft.web.administration.dll"

Compiling C# on the fly in Version 2

Add-Type -TypeDefinition @"
public class Test
{
    public static int Add(int n1, int n2)
    {
        return n1 + n2;
    }
}
"@

If you change the signature of the Add method you will get this error:

When compiling code on the fly or loading assemblies they cannot be unloaded.

.NET assemblies can’t be unloaded from a session (it’s a .NET thing, not a PowerShell thing) therefore DLLs can’t be unloaded from a session. This means that you can’t update a DLLs once it’s been loaded. We can’t even update the assembly on disk because the file is locked when the assembly is loaded.

- Bruce Payette Windows PowerShell in Action, Second Edition

Another way to use the –Path parameter on Add-Type

You can point to a C# source code file directly.

Add-Type –Path c:\test\Hello.cs

Add-Type is not limited to compiling only C#

You can inline these languages using the –Language parameter CSharp, CSharpVersion3, VisualBasic, JScript.

Notice, F# is not supported. Here is a post How to add an F# type to a PowerShell session that inlines F#.

NOTE: This uses the F# DLLs shipped with .NET 4.0

Add-TypeFSharp -TypeDefinition @"
module MyModule

let Add a b = a + b;;
"@                        

1..10 | % { [MyModule]::Add( $_, $_*2 ) }

Finally

There are additional parameters that the Add-Type cmdlet supports. You can generate a DLL file for the assembly with the specified name in the location, specify compiler parameters, specify assemblies which your code depends on and use wild cards when loading assemblies.

Check out the online help for Add-Type.

Because why anyone would want to write VBA in the Visual Studio macro editor is beyond me.

I agree!

Kurt lays out  the “how to” for injecting the Visual Studio’s DTE object (Development Tools Extensibility) into the F# console. He also provides the link to Visual Studio .NET Automation Object Model.

PowerShell PowerConsole

Makes accessing the Automation API simple. It brings the Visual Studio DTE automation object to your finger tips. Check this post for downloading PowerConsole – PowerShell Integrated with Visual Studio 2010.

$DTE.Solution.Projects | ForEach {$_.Fullname}

PS> $DTE.Solution.Projects | ForEach {$_.Fullname}

C:\PoShScripts\NYC Code Camp\CSharp\WPF+PoSh\Simple\Simple.csproj

C:\PoShScripts\NYC Code Camp\CSharp\WPF+PoSh\PowerShellExtensions\PowerShellExtensions.csproj

C:\PoShScripts\NYC Code Camp\CSharp\WPF+PoSh\HostAndAddVariables\HostAndAddVariables.csproj

No problem

Add-Type has a parameter CodeDomProvider and you can pass the FSharpCodeProvider to it (see the function Add-TypeFSharp).

Add-TypeFSharp lets you inline F# code.

Add-TypeFSharp -TypeDefinition @"
module MyModule

let Add a b = a + b;;
"@            
            
1..10 | % { [MyModule]::Add( $_, $_*2 ) }

Things TODO

• Install .NET 4.0, VS 2010 installs this and the latest F# bits
• Download and install The F# PowerPack
• Update the registry so PowerShell can work with .NET 4.0

Updating the registry

This is a bit tricky, thanks to the help of the PowerShell MVP community (Shay, Oisín, Marco and Vadims)on getting this to work.

Before you are allowed to edit this entry, you need to change the permissions on that key and take full ownership.

Then change the RuntimeVersion value, under the following key, to v4.0.30319.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PowerShell\1\PowerShellEngine

Function Add-TypeFSharp

Function Add-TypeFSharp {            
    param(            
        [string]$TypeDefinition                    
    )            
                
    Add-Type -Path `
        "C:\Program Files\FSharpPowerPack-1.9.9.9\bin\FSharp.Compiler.CodeDom.dll"            
                
    $provider = New-Object `
        Microsoft.FSharp.Compiler.CodeDom.FSharpCodeProvider            
                    
    Add-Type -TypeDefinition $TypeDefinition -CodeDomProvider $provider            
}

Notes

• Investigate using a PowerShell Proxy command for Add-Type and extend the Language parameter
• Enhance Add-TypeFSharp to take an F# file in addition to a string

The PowerConsole also supports IronPython and IronRuby.

Mongo (from "humongous") is a high-performance, open source, schema-free document-oriented database. MongoDB is written in C++ and offers the following features:

• Collection oriented storage: easy storage of object/JSON -style data
• Dynamic queries
• Full index support, including on inner objects and embedded arrays
• Query profiling
• Replication and fail-over support
• Efficient storage of binary data including large objects (e.g. photos and videos)
• Auto-sharding for cloud-level scalability

PowerShell

Dwight pointed out the way different languages could to talk to MongoDB and C# was one of them using a community developed driver.

Following the post Experimenting with MongoDB from C#, MongoDB was up and running and I was storing and retrieving data in no time.

F#

Looks like Matthew Podwysocki used the same reference and has MongoDB working with F#.

Some highlights of the code are:

• Foundational material on F# async programming, and samples including:
  • Fetching web pages in parallel
  • The Bing translator sample using async programming
  • A Graphical, asynchronous twitter client in 50 lines
  • A Twitter feed example that uses F# first class reactive event processing to process the stream of feeds
  • An asynchronous web crawler
  • Processing images in parallel, using a mixture of I/O and CPU parallelism
• An updated version of the famous Interactive DirectX demo
• Lots of great micro samples on foundational topics such as
  • object oriented programming
  • language oriented programming
  • function composition
  • design patterns
  • discriminated unions
  • records
  • units of measure

via F# in VS2010

Inline F# in PowerShell