PowerShell: How do I convert an array object to a string in PowerShell?

$a="This", 'Is', 'a', 'cat'

Using double quotes (and optionally use the separator $ofs)

# This Is a cat
"$a"

# This-Is-a-cat
$ofs="-" # after this all casts work this way until $ofs changes!
"$a"

Using operator join

# This-Is-a-cat
$a -join '-'

# ThisIsacat
-join $a

Using conversion to [string]

# This Is a cat
[string]$a

# This-Is-a-cat
$ofs="-"
[string]$a