if statement - Powershell if -lt problem; returns true if the condition is false

Question

I have a problem with small script in Powershell. Here is my script:

$number = Read-Host "Enter a number"
if ($number -lt 3){
    Write-Host "Number is too low."
    break
}

But when I enter 25, for example, the if conditional still evaluates to true.

Answer 1

Read-Host always returns a string, and -lt performs lexical comparison with a string as the LHS:

PS> '25' -lt 3
True  # because '2' comes lexically before '3'

You must convert the string returned from Read-Host to a number in order to perform numerical comparison:

[int] $number = Read-Host "Enter a number"
if ($number -lt 3){
    Write-Host "Number is too low."
    break
}