Copy entire list using Powershell CSOM sharepoint - powershell

Question

I need to export an entire list as a .csv file. I actually have this code which works great but I need to write each column I want to export:
$listTitle = "Example"
$list = $ctx.get_web().get_lists().getByTitle($listTitle);
$query = New-Object Microsoft.SharePoint.Client.CamlQuery;
$query.ViewXml = "<View><Query><Where><Geq><FieldRef Name='ID' /><Value Type='Counter'>1</Value></Geq></Where></Query></View>"
$listItems = $list.GetItems($query);
$ctx.Load($listItems);
$ctx.ExecuteQuery();
$tableau =#();
foreach ($listItem in $listItems)
{
$result = new-object psobject
$result | Add-Member -MemberType noteproperty -Name Title -value $listItem['Title'];
$result | Add-Member -MemberType noteproperty -Name Description -value $listItem['Description'];
$result | Add-Member -MemberType noteproperty -Name Age -value $listItem['Age'];
$result | Add-Member -MemberType noteproperty -Name Sexe -value $listItem['Sexe'];
$tableau += $result;
}
$CsvName2 = "Export_"+$ListTitle.replace(' ','_')+".csv"
$tableau | export-csv $CsvName2 -notype;
The part I want to improve is the foreach loop:
foreach ($listItem in $listItems)
{
$result = new-object psobject
$result | Add-Member -MemberType noteproperty -Name Title -value $listItem['Title'];
$result | Add-Member -MemberType noteproperty -Name Description -value $listItem['Description'];
$result | Add-Member -MemberType noteproperty -Name Age -value $listItem['Age'];
$result | Add-Member -MemberType noteproperty -Name Sexe -value $listItem['Sexe'];
$tableau += $result;
}
I want the script collects all columns but I don't know how to do it...
I got this advice: Replace my loop with:
foreach ($listItem in $listItems)
{
$result = new-object psobject
foreach ($field in $listItem.Fields)
{
if ($field.Hidden -eq $false)
{
$result | Add-Member -MemberType noteproperty -Name $field.Title -value $listItem[$field.InternalName];
}
}
$tableau += $result;
}
But all I got is a blank file. I don't really understand structure of list/filed items.
Thanks for your help.