Hash value not injecting other variable's value in powershell [duplicate]

Question

I have a hashtable like below in powershell

 $children = @{'key'='value\\$child\\Parameters'}

Now consider the below:

$child = "hey"
$parent = "$child ho"

Write-Host $parent

This prints

hey ho

so basically the string $parent is able to use the string $child defined. When expecting the same behavior from the value of the hashtable, this doesn't happen. For example:

$child = "hey"
$children = @{'key'='value\\$child\\Parameters'}

$children.GetEnumerator() | ForEach-Object {
$param = $_.Value
Write-Host $param
}

This prints

 value\\$child\\Parameters

instead of making use of $child and printing value\\hey\\Parameters I thought it might be because of the type so I tried using | Out-String and |% ToString with $_.Value to convert in to string but it still doesn't work. Any way to make use of $_.Value and still have the $child value injected?

Apologies but my vocab is more java-like than powershell.

In short: Only "..." strings (double-quoted aka expandable strings) perform string interpolation (expansion of variable values) in PowerShell, not '...' strings (single-quoted aka verbatim strings). If the string value itself contains " chars., escape them as `" or "", or use a double-quoted here-string. See the conceptual about_Quoting_Rules help topic. — mklement0
– mklement0, Commented May 9, 2022 at 13:29

user459872 · Accepted Answer · 2022-05-09 07:27:50Z

3

The problem here is with quotes. If you change the single quotes to double quotes you can see the interpolation will work as expected.

$child = "hey"
$children = @{"key"="value\\$child\\Parameters"}

Here is the relevant part from the documentation which explain this behaviour.

Single-quoted strings

A string enclosed in single quotation marks is a verbatim string. The string is passed to the command exactly as you type it. No substitution is performed.

Double-quoted strings

A string enclosed in double quotation marks is an expandable string. Variable names preceded by a dollar sign ($) are replaced with the variable's value before the string is passed to the command for processing.

edited May 9, 2022 at 7:27

answered May 9, 2022 at 7:21

user459872

25.9k4 gold badges51 silver badges74 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Hash value not injecting other variable's value in powershell [duplicate]

1 Answer 1

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Linked

Related