String

String Interpolation

Interpolated string should quote with ".

Use $ to interpolate:

• variable
• expression
• member accessing

"Profile Path: $Profile" # variable
"1 + 1 = $(1 + 1)" # expression

# functionaly identical
"cwd: $($pwd.Path)" # Member accessing
"cwd: $pwd"

"$(@(1, 2, 3)[0])"

NOTE

$() is being called SubExpression Operator in PowerShell.

Verbatim String

Verbatim string should quote with '. Can contains new lines and

'
    It''s a verbatim string! 
    and this is a new line!
'

NOTE

Verbatim string does not allow interpolation in PowerShell which differs from C#.

Raw String

NOTE

Raw string is being called Here String in PowerShell.

Here String typically allows string contents starting at the second line and truncates the last newline.

Use @'...'@ or @"..."@ to present Verbatim Here String or Interpolated Here String.

@"
    <foo>$Profile</foo>
"@

@'
    {
        "foo": {
            "bar": []
        }
    }
'@

NOTE

You can have quotation mark " in @"..."@ and for ' respectively.

Character Escaping

Quotation Mark

Use double " to escape " in a interpolated string.

"""""" # ""
"I quote, ""haha!""" # I quote, "haha!"

Or use ` to escape the same quotation mark in the containing quotation.

"I quote, `"haha!`""

Use double ' to escape ' in a verbatim string.

'''''' # ''
'I quote, ''haha!''' # I quote, 'haha!'

NOTE

See about_Specical_Characters

Arithmetic with Numerics

PowerShell will try to convert the string on the right operand to the same type as left operand. Exception will be raised if conversion failed.

1 + '2' # 3
'2' + 1 # '21'
[DateTime]::Now + '00:00:15:00' # adds 15 minutes

Split & Join

'1,2,3' -split ',' # 1 2 3 as strings
(gci -file) -join ',' # ToString is invoked to evaluated objects to string.

Match & Replace

PowerShell has two kinds of matching strategy for strings.

• -match for regex matching.
• -like for wildcard matching.

While -replace only supports regex.

TIP

Match and replace is case-insensitive by default. Use -cmatch, -cnotmatch, -creplace, -csplit for case-sensitive scenarios.

'Janet is a girl' -match 'Jane' # True
'Janet is a girl' -replace '^Janet', 'Jane'
'Janet is a girl' -replace '^Janet', 'Jane' -replace 'is', 'is not' # replace multiple times inline.

All previous matches and captured groups can be accessed in $matches builtin variable. $matches is a HashTable, you can access named capture group by group name and use index for unamed group.

if ('John Smith' -match '^(?<FirstName>\b\w+\b) (\b\w+\b)$') {
    $matches.FirstName # John
    $matches[0] # John Smith
    $matches[1] # Smith
}

Format String

Template string syntax is the same as C#. Standard numeric format like :C, :X are supported.

'This is a {0} string' -f 'format'

Repetition

Use * to repeat a string.

'abc' * 2 # abcabc

String Evaluation in Interpolation

Collection

Collections like Array and HashTable are formatted by certain separator defined by $OFS(Output Field Separator)

"$(1, 2, 3)" # 1 2 3

NOTE

$OFS is not a builtin variable, you'll have to create it manually or pwsh uses space as the separator.