I am trying to write a regex on powershell for the canadian addresses

Question

this is the address method

the number might be different 12 or 412 and how many words for the finch ave east

1460 Finch Ave East, Toronto, Ontario, A1A1A1

so I try this

^[0-9]+\s+[a-zA-Z]+\s+[a-zA-Z]+\s+[a-zA-Z]+[,]{1}+\s[a-zA-Z]+[,]{1}+\s+[a-zA-Z]+[,]{1}+\s[A-Za-z]\d[A-Za-z][ -]?\d[A-Za-z]\d$

Answer 1

I usually recommend using regex capture-groups, so you can break and simplify your matching problem to smaller sets. For most cases I use \d and \w, s for matching numbers, standard letters and whitespaces.

I usually experiment on https://regex101.com before I put it into code, because it provides a nice interactive way to play with expressions and samples.

Regarding your question the expression that I came up is:

$regexp = "^(\d+)\s*((\w+\s*)+),\s*(\w+),\s*(\w+),\s*((\w\d)*)$"

In PowerShell I like to use the direct regex class, because it offers more granularity than the standard -match operator.

# Example match and results
$sample = "1460 Finch Ave East, Toronto, Ontario, A1A1A1"
$match = [regex]::Match($sample, $regexp)
$match.Success
$match | Select -ExpandProperty groups | Format-Table Name, Value

# Constructed fields
@{
    number = $match.Groups[1]
    street = $match.Groups[2]
    city = $match.Groups[4]
    state = $match.Groups[5]
    areacode = $match.Groups[6]
}

So this will result in $match.Success $true and the following numbered capture-groups will be presented in the Groups list:

Name Value
---- -----
0    1460 Finch Ave East, Toronto, Ontario, A1A1A1
1    1460
2    Finch Ave East
3    East
4    Toronto
5    Ontario
6    A1A1A1
7    A1

For constructing the fields, you can ignore 3 and 7 as those are partial-groups:

Name     Value
----     -----
areacode A1A1A1
street   Finch Ave East
city     Toronto
state    Ontario
number   1460

Answer 2

To add to mákos excellent answer, I would suggest using named capture groups and the $Matches automatic variable. This makes it super easy to grab the individual fields and turn them into objects for multiple input strings:

function Split-CanadianAddress {
  param(
    [Parameter(Mandatory,ValueFromPipeline)]
    [string[]]$InputString
  )

  $Pattern = "^(?<Number>\d+)\s*(?<Street>(\w+\s*)+),\s*(?<City>(\w+\s*)+),\s*(?<State>(\w+\s*)+),\s*(?<AreaCode>(\w\d)*)$"

  foreach($String in $InputString){
    if($String -match $Pattern){
      $Fields = @{}
      $Matches.Keys |Where-Object {$_ -isnot [int]} |ForEach-Object {
        $Fields.Add($_,$Matches[$_])
      }
      [pscustomobject]$Fields
    }
  }
}

The $Matches hashtable will contain both the numbered and named capture groups, which is why I copy only the named entries to the $Fields variable before creating the pscustomobject

Now you can use it like:

PS C:\> $sample |Split-CanadianAddress

Street   : Finch Ave East
State    : Ontario
AreaCode : A1A1A1
Number   : 1460
City     : Toronto

I've update the pattern to allow for spaces in city and state names as well (think "New Westminster, British Columbia")