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Use the new PowerShell cmdlet Convert-String to parse email addresses

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image_thumb[9]Tired of hacking away at RegEx and string functions to parse text? This post is for you!

New toys

PowerShell 5.x includes a number of new features. One of the lesser-known and incredibly powerful is the string conversion set of cmdlets. The names are very similar. Check out how Get-Help describes them:

 PS C:\> Get-Help Convert*-String | Format-Table Name,Synopsis -AutoSize

Name               Synopsis
----               --------
Convert-String     Formats a string to match examples.
ConvertFrom-String Extracts and parses structured objects from string content.

Convert-String

I will admit that doesn’t sound very interesting on first glance. But check out what they can do! Let’s start with a simple example of Convert-String:

 'Alice Alpha <alice.alpha@contoso.com>;' |            
Convert-String -Example 'Alice Alpha <alice.alpha@contoso.com>;=Alice,Alpha,alice.alpha@contoso.com'

The -Example parameter is a string set up as SampleData=DesiredFormat. The above example will parse Alice's name and email into clean CSV data. It doesn’t always have to be CSV, but that is what I need for this use case.

 Alice,Alpha,alice.alpha@contoso.com

1up

Now let’s take a list of email addresses pasted from Outlook. Notice that we pipe them to –Split, giving us an array for string conversion split on new lines:

 $Emails = @"
Alice Alpha <alice.alpha@contoso.com>;
Bob Beta <bob.beta@contoso.com>;
Charlie Charles <charlie.charles@contoso.com>;
Doug Delta <doug.delta@contoso.com>
"@ -Split "`n"            
            
$Emails |            
Convert-String -Example 'Alice Alpha <alice.alpha@contoso.com>;=Alice,Alpha,alice.alpha@contoso.com'

This code turns a list of email addresses into nice CSV data. Because the addresses are all formatted similarly, the one example of Alice shows how to parse all the lines.

 Alice,Alpha,alice.alpha@contoso.com
Bob,Beta,bob.beta@contoso.com
Charlie,Charles,charlie.charles@contoso.com
Doug,Delta,doug.delta@contoso.com

CSV baby!

Let’s add ConvertFrom-CSV to include some headers.

 $Emails = @"
Alice Alpha <alice.alpha@contoso.com>;
Bob Beta <bob.beta@contoso.com>;
Charlie Charles <charlie.charles@contoso.com>;
Doug Delta <doug.delta@contoso.com>
"@ -Split "`n"            
            
$Emails |            
Convert-String -Example 'Alice Alpha <alice.alpha@contoso.com>;=Alice,Alpha,alice.alpha@contoso.com' |            
ConvertFrom-Csv -Header 'FirstName','LastName','Email'

Now we have clean PowerShell object output for a list of email addresses pasted from Outlook. Cool!

 FirstName LastName Email                      
--------- -------- -----                      
Alice     Alpha    alice.alpha@contoso.com    
Bob       Beta     bob.beta@contoso.com       
Charlie   Charles  charlie.charles@contoso.com
Doug      Delta    doug.delta@contoso.com

Convert-String works with a single parsing example. If you have a variety of complex patterns to parse, then use ConvertFrom-String instead. We will look at that in tomorrow’s post.

Your turn…

I decided to keep this post short and leave other things for you to discover with the cmdlet. I have shown you one way to use it. There is more! Get-Help is your friend.

Now take this and go parse some of your own flat text use cases. Use the comments below to share your challenges and victories. Enjoy!

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