Is there a way to force powershell -Export-CSV cmdlet to maintain a specific column order?

Question

I'm new to powershell, so the script is a Frankenstein of various examples of from sites.

My question is how can I make sure that a csv file I am creating for a DataTable keeps the column order I specify?

My script does this to populate the csv headers and values like so:

...snip...
$dataTable | ForEach-Object {
            $csv+=New-Object PSObject -Property @{
                program_code=$_.ProgramCode;
                first_name=$_.FirstName;
                last_name=$_.LastName;
                email=$_.email;
                phone=$_.phone;
                phone2=$_.otherphone;
                address=$_.addr1;
                address2=$_.addr2;
                city=$_.city;
                state=$_.state;
                postal_code=$_.Zip;
                country=$_.Country;
                grad_year=$_.HsGradDate;
                lead_date=$_.LeadDate;
                lead_source=$_.LeadSource;
                school_status=$_.SchoolStatus;
        }
        }
    $csv | Export-CSV C:\scripts\NewLeads$(Get-Date -Format yyyyMMdd).csv -notype -Append
...snip...

I want the file to have to columns in the order that I specify in the script, but when I open it in notepad or excel the columns appear in a seemingly random order. Keyword being seemingly since they may have some method of ordering themselves.

Answer 1

In PowerShell V3, instead of:

        $csv+=New-Object PSObject -Property @{

I would use:

        $csv+=[pscustomobject]@{

The PowerShell V3 parser will preserve the order of the keys when you cast a hash literal to either [ordered] or [pscustomobject]. A small side benefit to this approach - it will also be faster.

If you are using V2, you'll need to skip the -Property parameter to New-Object and instead use multiple calls to Add-Member. It will look something like:

$csv+=New-Object PSObject |
    Add-Member -Name program_code -Value $_.ProgramCode -MemberType NoteProperty -PassThru |
    Add-Member -Name first_name -Value $_.FirstName -MemberType NoteProperty -PassThru |
    ...