How to convert powershell array to table

If the data you show is indeed the output of a Fixed-Width file, you need to try and get the widths for each field in order to parse it. A handicap here is that the original header names contain a space character and we need to replace that by an underscore.

For that, you can use the below function:

function ConvertFrom-FixedWith {
    [CmdletBinding()]
    Param(
        [Parameter(Mandatory = $true, Position = 0)]
        [string[]]$Content
    )

    $splitter   = '§¤¶'             # some unlikely string: Alt-21, [char]164, Alt-20  
    $needQuotes = '^\s+|[",]|\s+$'  # quote the fields if needed

    function _FWClean ([string]$field) {
        # internal helper function to clean a field value with regards to quoted fields
        $field = $_.Trim() -replace '(?<!\\)\\"|""', '§DQUOTE¶'
        if ($field -match '^"(.*)"$')  { $field = $matches[1] }
        if ($field -match $needQuotes) { $field = '"{0}"' -f $field }
        return $field -replace '§DQUOTE¶', '""'
    }

    # try and calculate the field widths using the first header line
    # this only works if none of the header names have spaces in them
    # and where the headers are separated by at least one space character.

    Write-Verbose "Calculating column widths using first row"
    $row = ($Content[0] -replace '\s+', ' ').Trim()
    $fields = @($row -split ' ' ) # | ForEach-Object { _FWClean $_ })
    $ColumnBreaks = for ($i = 1; $i -lt $fields.Length; $i++) {
        $Content[0].IndexOf($fields[$i]) 
    }
    $ColumnBreaks = $ColumnBreaks | Sort-Object -Descending

    Write-Verbose "Splitting fields and generating output"
    $Content | ForEach-Object {
        if ($null -ne $_ -and $_ -match '\S') {
            $line = $_
            # make sure lines that are too short get padded on the right
            if ($line.Length -le $ColumnBreaks[0]) { $line = $line.PadRight(($ColumnBreaks[0] + 1), ' ') }
            # add the splitter string on every column break point
            $ColumnBreaks | ForEach-Object { 
                $line = $line.Insert($_, $splitter)
            }
            # split on the splitter string, trim, and dedupe possible quotes
            # then join using the delimiter character
            @($line -split $splitter | ForEach-Object { _FWClean $_ }) -join ','
        }
    } | ConvertFrom-Csv    # the result is an array of PSCustomObjects
}

With that function in place, parsing the text can be done like so:

$text = @"
Customer_ID        Client_Name        Computer_Name        Computer_Brand        Duration        Connection_Time        Lang
123                first last         127.0.0.1            lenovo                10:00           8/18/2019 6:00 PM      Eng
1                  lastname           127.0.0.2            apple                 2:30:00         8/18/2019 1:00 AM      Chn  
86                 user3              127.0.0.1            dell                                  8/18/2019 2:00 PM 
21                 user4              127.0.0.4            apple                 30:00           8/17/2019 1:00 PM      Eng
"@ -split '\r?\n'

# replace the single space characters in the header names by underscore
$text[0] = $text[0] -replace '(\w+) (\w+)', '$1_$2'

# the 'ConvertFrom-FixedWith' function takes a string array as input
$table = ConvertFrom-FixedWith -Content $text

#output on screen
$table | Format-Table -AutoSize

# export to CSV file
$table | Export-Csv -Path 'D:\test.csv' -NoTypeInformation

Output (on screen)

Customer ID Client Name Computer Name Computer Brand Duration Connection Time   Lang
----------- ----------- ------------- -------------- -------- ---------------   ----
123         first last  127.0.0.1     lenovo         10:00    8/18/2019 6:00 PM Eng 
1           lastname    127.0.0.2     apple          2:30:00  8/18/2019 1:00 AM Chn 
86          user3       127.0.0.1     dell                    8/18/2019 2:00 PM     
21          user4       127.0.0.4     apple          30:00    8/17/2019 1:00 PM Eng 

If your input $text is already a string array storing all the ines as we see them in your question, then leave out the -split '\r?\n'

function Get-DurationInMinutes ([string]$Duration) {
    $h, $m, $s = (('0:{0}' -f $Duration) -split ':' | Select-Object -Last 3)
    return [int]$h * 60 + [int]$m
}

($table | Where-Object { (Get-DurationInMinutes $_.Duration) -ge 30 }).Customer_ID

This will output

1
21

Now that we finally know the data is from a TAB delimited CSV file, you don't need the ConvertFrom-FixedWith function.

Simply import the data using if it comes from a file

$table = Import-Csv -Path 'D:\customers.csv' -Delimiter "`t"

Or, if it comes from the output of another command as string or string array:

$table = $original_output | ConvertFrom-Csv -Delimiter "`t"

Then, use the Get-DurationInMinutes helper function just like above to get the Customer ID's that are connected for more than 30 minutes:

function Get-DurationInMinutes ([string]$Duration) {
    $h, $m, $s = (('0:{0}' -f $Duration) -split ':' | Select-Object -Last 3)
    return [int]$h * 60 + [int]$m
}

($table | Where-Object { (Get-DurationInMinutes $_.Duration) -ge 30 }).'Customer ID'

Uhh. I'm surprised there's not a canonical way to do this. Based on https://www.reddit.com/r/PowerShell/comments/211ewa/how_to_convert_fixedwidth_to_pipedelimited_or/.

# 0                  19                 38                   59                    81              97                     120 123
# Customer ID        Client Name        Computer Name        Computer Brand        Duration        Connection Time        Lang
# 123                first last         127.0.0.1            lenovo                10:00           8/18/2019 6:00 PM      Eng
# 1                  lastname           127.0.0.2            apple                 2:30:00         8/18/2019 1:00 AM      Chn
# 86                 user3              127.0.0.1            dell                                  8/18/2019 2:00 PM
# 21                 user4              127.0.0.4            apple                 30:00           8/17/2019 1:00 PM      Eng


$cols = 0,19,38,59,81,97,120,123 # fake extra column at the end, assumes all rows are that wide

$firstline = get-content columns.txt | select -first 1
$headers = for ($i = 0; $i -lt $cols.count - 1; $i++) {
  $firstline.substring($cols[$i], $cols[$i+1]-$cols[$i]).trim()
}

# string Substring(int startIndex, int length)

$lines = Get-Content columns.txt | select -skip 1 
$lines | ForEach {
  $hash = [ordered]@{}
  for ($i = 0; $i -lt $headers.length; $i++) {
    $hash += @{$headers[$i] = $_.substring($cols[$i], $cols[$i+1]-$cols[$i]).trim()}
  }
  [pscustomobject]$hash
} 

Output:

PS /Users/js/foo> ./columns | ft

Customer ID Client Name Computer Name Computer Brand Duration Connection Time   Lan
----------- ----------- ------------- -------------- -------- ---------------   ---
123         first last  127.0.0.1     lenovo         10:00    8/18/2019 6:00 PM Eng
1           lastname    127.0.0.2     apple          2:30:00  8/18/2019 1:00 AM Chn
86          user3       127.0.0.1     dell                    8/18/2019 2:00 PM 
21          user4       127.0.0.4     apple          30:00    8/17/2019 1:00 PM Eng