Select specific column based on data supplied using Powershell - powershell

Question

I have a csv file that may have unknown headers, one of the columns will contain email addresses for example.
Is there a way to select only the column that contains the email addresses and save it as a list to a variable?
One csv could have the header say email, another could say emailaddresses, another could say email addresses another file might not even have the word email in the header. As you can see, the headers are different. So I want to be able to detect the correct column first and use that data further in the script. Once the column is identified based on the data it contains, select that column only.
I've tried the where-object and select-string cmdlets. With both, the output is the entire array and not just the data in the column I am wanting.
$CSV = import-csv file.csv
$CSV | Where {$_ -like "*#domain.com"}
This outputs the entire array as all rows will contain this data.

Answer 1

Sample Data for visualization
id,first_name,bagel,last_name
1,Base,bcruikshank0#homestead.com,Cruikshank
2,Regan,rbriamo1#ebay.co.uk,Briamo
3,Ryley,rsacase2#mysql.com,Sacase
4,Siobhan,sdonnett3#is.gd,Donnett
5,Patty,pesmonde4#diigo.com,Esmonde
Bagel is obviously what we are trying to find. And we will play pretend in that we have no knowledge of the columns name or position ahead of time.
Find column dynamically
# Import the CSV
$data = Import-CSV $path
# Take the first row and get its columns
$columns = $data[0].psobject.properties.name
# Cycle the columns to find the one that has an email address for a row value
# Use a VERY crude regex to validate an email address.
$emailColumn = $columns | Where-Object{$data[0].$_ -match ".*#*.\..*"}
# Example of using the found column(s) to display data.
$data | Select-Object $emailColumn
Basically read in the CSV like normal and use the first columns data to try and figure out where the email address column is. There is a caveat that if there is more than one column that matches it will get returned.
To enforce only 1 result a simple pipe to Select-Object -First 1 will handle that. Then you just have to hope the first one is the "right" one.

Answer 2

If you're using Import-Csv, the result is a PSCustomObject.
$CsvObject = Import-Csv -Path 'C:\Temp\Example.csv'
$Header = ($CsvObject | Get-Member | Where-Object { $_.Name -like '*email*' }).Name
$CsvObject.$Header
This filters for the header containing email, then selects that column from the object.
Edit for requirement:
$Str = #((Get-Content -Path 'C:\Temp\Example.csv') -like '*#domain.com*')
$Headers = #((Get-Content -Path 'C:\Temp\Example.csv' -TotalCount 1) -split ',')
$Str | ConvertFrom-Csv -Delimiter ',' -Header $Headers

Answer 3

Other method:
$PathFile="c:\temp\test.csv"
$columnName=$null
$content=Get-Content $PathFile
foreach ($item in $content)
{
$SplitRow= $item -split ','
$Cpt=0..($SplitRow.Count - 1) | where {$SplitRow[$_] -match ".*#*.\..*"} | select -first 1
if ($Cpt)
{
$columnName=($content[0] -split ',')[$Cpt]
break
}
}
if ($columnName)
{
import-csv "c:\temp\test.csv" | select $columnName
}
else
{
"No Email column founded"
}