Can I get “&&” or “-and” to work in PowerShell?

Question

&& is notoriously hard to search for on Google Search, but the best I've found is this article which says to use -and.

Unfortunately it doesn't give any more information, and I can't find out what I'm supposed to do with -and (again, a notoriously hard thing to search for).

The context I'm trying to use it in is "execute cmd1, and if successful, execute cmd2", basically this:

csc /t:exe /out:a.exe SomeFile.cs && a.exe

---

If you just want to run multiple commands on a single line and you don't care if the first one fails or not, you can use ; For most of my purposes this is fine.

For example: kill -n myapp; ./myapp.exe.

Answer 1

In CMD, '&&' means "execute command 1, and if it succeeds, execute command 2". I have used it for things like:

build && run_tests

In PowerShell, the closest thing you can do is:

(build) -and (run_tests)

It has the same logic, but the output text from the commands is lost. Maybe it is good enough for you, though.

If you're doing this in a script, you will probably be better off separating the statements, like this:

build
if ($?) {
    run_tests
}

2019/11/27: The &&operator is now available for PowerShell 7 Preview 5+:

PS > echo "Hello!" && echo "World!"
Hello!
World!

Answer 2

&& and || were on the list of things to implement (still are) but did not pop up as the next most useful thing to add. The reason is that we have -AND and -OR. If you think it is important, please file a suggestion on Connect and we'll consider it for V3.

Answer 3

Try this:

$errorActionPreference='Stop'; csc /t:exe /out:a.exe SomeFile.cs; a.exe

Answer 4

If your command is available in cmd.exe (something like python ./script.py, but not PowerShell command like ii . (this means to open the current directory by Windows Explorer)), you can run cmd.exe within PowerShell. The syntax is like this:

cmd /c "command1 && command2"

Here, && is provided by cmd syntax described in this question.

Answer 5

I tried this sequence of commands in PowerShell:

First Test

PS C:\> $MyVar = "C:\MyTxt.txt"
PS C:\> ($MyVar -ne $null) -and (Get-Content $MyVar)
True

($MyVar -ne $null) returned true and (Get-Content $MyVar) also returned true.

Second Test

PS C:\> $MyVar = $null
PS C:\> ($MyVar -ne $null) -and (Get-Content $MyVar)
False

($MyVar -ne $null) returned false and so far I must assume the (Get-Content $MyVar) also returned false.

The third test proved the second condition was not even analyzed.

PS C:\> ($MyVar -ne $null) -and (Get-Content "C:\MyTxt.txt")
False

($MyVar -ne $null) returned false and proved the second condition (Get-Content "C:\MyTxt.txt") never ran, by returning false on the whole command.

Answer 6

Just install PowerShell 7 (go here, and scroll and expand the assets section). This release has implemented the pipeline chain operators.

Answer 7

Very old question, but for the newcomers: maybe the PowerShell version (similar but not equivalent) that the question is looking for, is to use -and as follows:

(build_command) -and (run_tests_command)

Answer 8

A verbose equivalent is to combine $LASTEXITCODE and -eq 0:

msbuild.exe args; if ($LASTEXITCODE -eq 0) { echo 'it built'; } else { echo 'it failed'; }

I'm not sure why if ($?) didn't work for me, but this one did.

Answer 9

Use:

if (start-process filename1.exe) {} else {start-process filename2.exe}

It's a little longer than "&&", but it accomplishes the same thing without scripting and is not too hard to remember.

Answer 10

I think a simple if statement can accomplish this. Once I saw mkelement0's response that the last exit status is stored in $?, I put the following together:

# Set the first command to a variable
$a=somecommand

# Temporary variable to store exit status of the last command (since we can't write to "$?")
$test=$?

# Run the test
if ($test=$true) { 2nd-command }

So for the OP's example, it would be:

a=(csc /t:exe /out:a.exe SomeFile.cs); $test = $?; if ($test=$true) { a.exe }

Answer 11

It depends on the context, but here's an example of "-and" in action:

get-childitem | where-object { $_.Name.StartsWith("f") -and $_.Length -gt 10kb }

So that's getting all the files bigger than 10kb in a directory whose filename starts with "f".

Answer 12

We can try this command instead of using && method:

try {hostname; if ($lastexitcode -eq 0) {ipconfig /all | findstr /i bios}} catch {echo err} finally {}