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

How can I convert an array object to string?

I tried:

$a = "This", "Is", "a", "cat"
[system.String]::Join(" ", $a)

~~with no luck~~. What are different possibilities in PowerShell?

6 Answers

$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

I found that piping the array to the Out-String cmdlet works well too.

For example:

PS C:\> $a | out-string
This
Is
a
cat

It depends on your end goal as to which method is the best to use.

1> $a = "This", "Is", "a", "cat"
2> [system.String]::Join(" ", $a)

Line two performs the operation and outputs to host, but does not modify $a:

3> $a = [system.String]::Join(" ", $a)
4> $a
This Is a cat
5> $a.Count
1

From a pipe

# This Is a cat
'This', 'Is', 'a', 'cat' | & {"$input"}
# This-Is-a-cat
'This', 'Is', 'a', 'cat' | & {$ofs='-';"$input"}

Write-Host

# This Is a cat
Write-Host 'This', 'Is', 'a', 'cat'
# This-Is-a-cat
Write-Host -Separator '-' 'This', 'Is', 'a', 'cat'

You could specify type like this:

[string[]] $a = "This", "Is", "a", "cat"

Checking the type:

$a.GetType()

Confirms:

 IsPublic IsSerial Name BaseType -------- -------- ---- -------- True True String[] System.Array

Outputting $a:

PS C:\> $a
This
Is
a
cat

$a = "This", "Is", "a", "cat"
foreach ( $word in $a ) { $sent = "$sent $word" }
$sent = $sent.Substring(1)
Write-Host $sent