Powershell Array to comma separated string with Quotes

Here you go:

[array]$myArray = '"file1.csv"','"file2.csv"'
[string]$a = $null

$a = $myArray -join ","

$a

Output:

"file1.csv","file2.csv"

You just have to get a way to escape the ". So, you can do it by putting around it '.