In PowerShell, how can I test if a variable holds a numeric value?

Question

In PowerShell, how can I test if a variable holds a numeric value?

Currently, I\'m trying to do it like this, but it always seems to return false.

Answer 1

filter isNumeric {
    $_ -is [ValueType]
}

-

1 -is [ValueType]
True
"1" -is [ValueType]
False

-

function isNumeric ($Value) {
    return $Value -is [ValueType]
}

isNumeric 1.23
True
isNumeric 123
True
isNumeric ""
False
isNumeric "asdf123"
False

-

(Invoke-Expression '1.5') -is [ValueType]