Suppose I have the following snippet:
$assoc = New-Object PSObject -Property @{ Id = 42 Name = "Slim Shady" Owner = "Eminem" } Write-Host $assoc.Id + " - " + $assoc.Name + " - " + $assoc.Owner I'd expect this snippet to show:
42 - Slim Shady - Eminem
But instead it shows:
42 + - + Slim Shady + - + Eminem
Which makes me think the + operator isn't appropriate for concatenating strings and variables.
How should you approach this with PowerShell?
222 Answers
Write-Host "$($assoc.Id) - $($assoc.Name) - $($assoc.Owner)" See the Windows PowerShell Language Specification Version 3.0, p34, sub-expressions expansion.
7There is a difference between single and double quotes. (I am using PowerShell 4).
You can do this (as Benjamin said):
$name = 'Slim Shady' Write-Host 'My name is'$name -> My name is Slim Shady Or you can do this:
$name = 'Slim Shady' Write-Host "My name is $name" -> My name is Slim Shady The single quotes are for literal, output the string exactly like this, please. The double quotes are for when you want some pre-processing done (such as variables, special characters, etc.)
So:
$name = "Marshall Bruce Mathers III" Write-Host "$name" -> Marshall Bruce Mathers III Whereas:
$name = "Marshall Bruce Mathers III" Write-Host '$name' -> $name (I find How-to: Escape characters, Delimiters and Quotes good for reference).
4You can also use -join
E.g.
$var = -join("Hello", " ", "world"); Would assign "Hello world" to $var.
So to output, in one line:
Write-Host (-join("Hello", " ", "world")) 5One way is:
Write-Host "$($assoc.Id) - $($assoc.Name) - $($assoc.Owner)" Another one is:
Write-Host ("{0} - {1} - {2}" -f $assoc.Id,$assoc.Name,$assoc.Owner ) Or just (but I don't like it ;) ):
Write-Host $assoc.Id " - " $assoc.Name " - " $assoc.Owner 2Try wrapping whatever you want to print out in parentheses:
Write-Host ($assoc.Id + " - " + $assoc.Name + " - " + $assoc.Owner) Your code is being interpreted as many parameters being passed to Write-Host. Wrapping it up inside parentheses will concatenate the values and then pass the resulting value as a single parameter.
Another option is:
$string = $assoc.ID $string += " - " $string += $assoc.Name $string += " - " $string += $assoc.Owner Write-Host $string The "best" method is probably the one C.B. suggested:
Write-Host "$($assoc.Id) - $($assoc.Name) - $($assoc.Owner)" 4While expression:
"string1" + "string2" + "string3" will concatenate the string, you need to put a $ in front of the parenthesis to make it evaluate as a single argument when passed to a PowerShell command. Example:
Write-Host $( "string1" + "string2" + "string3" ) As a bonus, if you want it to span multiple lines, then you need to use the awkward backtick syntax at the end of the line (without any spaces or characters to the right of the backtick).
Example:
Write-Host $(` "The rain in " +` "Spain falls mainly " +` "in the plains" )` -ForegroundColor Yellow (Actually, I think PowerShell is currently implemented a little bit wrong by requiring unnecessary backticks between parentheses. If Microsoft would just follow Python or Tcl parenthesis rules of allowing you to put as many newlines as you want between the starting and ending parenthesis then they would solve most of the problems that people don't like about PowerShell related to line continuation, and concatenation of strings.
I've found that you can leave the backticks off sometimes on line continuations between parenthesis, but it's really flaky and unpredictable if it will work... It's better to just add the backticks.)
You need to place the expression in parentheses to stop them being treated as different parameters to the cmdlet:
Write-Host ($assoc.Id + " - " + $assoc.Name + " - " + $assoc.Owner) 1(Current PowerShell version 5.1.17134.407)
This also works as of now:
$myVar = "Hello" echo "${myVar} World" Note: this only works with double quotes
0Here is another way as an alternative:
Write-Host (" {0} - {1} - {2}" -f $assoc.Id, $assoc.Name, $assoc.Owner) I just want to bring another way to do this using .NET String.Format:
$name = "Slim Shady" Write-Host ([string]::Format("My name is {0}", $name)) 2I seem to struggle with this (and many other unintuitive things) every time I use PowerShell after time away from it, so I now opt for:
[string]::Concat("There are ", $count, " items in the list") 1These answers all seem very complicated. If you are using this in a PowerShell script you can simply do this:
$name = 'Slim Shady' Write-Host 'My name is'$name It will output
My name is Slim Shady
Note how a space is put between the words for you
Concatenate strings just like in the DOS days. This is a big deal for logging so here you go:
$strDate = Get-Date $strday = "$($strDate.Year)$($strDate.Month)$($strDate.Day)" Write-Output "$($strDate.Year)$($strDate.Month)$($strDate.Day)" Write-Output $strday 1From What To Do / Not to Do in PowerShell: Part 1:
$id = $assoc.Id $name = $assoc.Name $owner = $assoc.owner "$id - $name - $owner" Write-Host can concatenate like this too:
Write-Host $assoc.Id" - "$assoc.Name" - "$assoc.Owner This is the simplest way, IMHO.
If you're concatenating strings to build file paths, use the Join-Path command:
Join-Path C:\temp "MyNewFolder" It'll automatically add the appropriate trailing / leading slashes for you, which makes things a lot easier.
$assoc = @{ Id = 34 FirstName = "John" LastName = "Doe" Owner = "Wife" } $assocId = $assoc.Id $assocFN = $assoc.FirstName $assocLN = $assoc.LastName $assocName = $assocFN, $assocLN -Join " " $assocOwner = $assoc.Owner $assocJoin = $assocId, $assocName, $assocOwner -join " - " $assocJoin #Output = 34 - John Doe - Wife Personally I prefer this style:
[string]::Join(' - ', 42, 'Slim Shady', 'Eminem') or based on the above (unordered) object:
[string]::Join(' - ',$assoc.psObject.Properties.value) You can also get access to C#/.NET methods, and the following also works:
$string1 = "Slim Shady, " $string2 = "The real slim shady" $concatString = [System.String]::Concat($string1, $string2) Output: Slim Shady, The real slim shady 0Just for the fun. You can also access the values of the PSObject directly like below:
$assoc.psobject.Properties.value -join " - " But if you do not specify that the object should be ordered, PowerShell will display the values in a random order. So you should add the flag [ordered]:
$assoc = [pscustomobject] [ordered] @{ Id = 42 Name = "Slim Shady" Owner = "Eminem" } 1As noted elsewhere, you can use join.
If you are using commands as inputs (as I was), use the following syntax:
-join($(Command1), "," , $(Command2)) This would result in the two outputs separated by a comma.