powershell: how to write-host value from [ref] variable

I'm new to Powershell and I'm trying to work out how to print the value of a [ref] variable from within a function.

Here is my test code:



function testref([ref]$obj1) {
$obj1.value = $obj1.value + 5
write-host "the new value is $obj1"
$obj1 | get-member
}


$foo = 0
"foo starts with $foo"
testref([ref]$foo)
"foo ends with $foo"


The output I get from this test is as follows. You'll notice that I don't get the value of $obj1 as I was hoping. I also tried passing in $obj1.value in the call to write-host but that generated the same response.

PS > .\testref.ps1
foo starts with 0
the new value is System.Management.Automation.PSReference


TypeName: System.Management.Automation.PSReference

Name MemberType Definition
---- ---------- ----------
Equals Method bool Equals(System.Object obj)
GetHashCode Method int GetHashCode()
GetType Method type GetType()
ToString Method string ToString()
Value Property System.Object Value {get;set;}
foo ends with 5

You would have probably tried:

write-host "the new value is $obj1.value"

and got corresponding output of

the new value is System.Management.Automation.PSReference.value

I think you did not notice the `.value` in the end of the output.

In strings you have to do something like this while accessing properties:

write-host "the new value is $($obj1.value)"

Or use string format, like this:

write-host ("the new value is {0}" -f $obj1.value)

Or assign value outside like `$value = $obj1.value` and use in string.