包含switch语句的脚本块不起作用

Question

我在脚本块内的switch语句中遇到错误。选项1正在执行，但是2和3不起作用。

$server = Read-Host -Prompt 'Enter the server name:'
$cred   = Get-Credential

$choice = {
    Param([int]$opt)

    switch ($opt) {
        1 {
            Set-ExecutionPolicy Remotesigned -Force
            $EP = Get-ExecutionPolicy
            echo "Executionpolicy:$EP"
        }
        2 {
            Restart-Service WinRM
            $RM = Get-Service WinRM | Select Status
            $RM = $RM.Status
            $RMT = Test-WSMan
            echo "WinRM status: $RM"
            echo "Testing WSMan......"
            $RMT
        }
        3 {
            Set-ExecutionPolicy Remotesigned -Force
            Restart-Service WinRM
            $RM = Get-Service WinRM | Select Status
            $RM = $RM.Status
            $EP = Get-ExecutionPolicy
            echo "WinRM status: $RM"
            echo "Executionpolicy:$EP"
            $RMT = Test-WSMan
            echo "Testing WSMan......"
            $RMT
        }
    }
    Exit-PSSession
} 

if (Test-Connection $server -Quiet) {
    $session = New-PSSession -ComputerName $server -Authentication Default -Credential $cred
    Invoke-Command -Session $session -ScriptBlock {
        $EP = Get-ExecutionPolicy
        $RM = Get-Service WinRM | Select Status
        $RM = $RM.Status
        Echo "**********************************************"
        Echo "Executionpolicy:$EP"
        echo "WinRM status: $RM"
        Echo "**********************************************"
        Exit-PSSession
    }

    $op = @"
    ====Option number for changes====
    1.Execution Policy
    2.WinRM restart
    3.Both
    ==================================
"@
    $op
    $opt = Read-Host -Prompt 'Enter the option number for changes:'

    Invoke-Command -Session $session -ArgumentList $opt -ScriptBlock $choice -
    Remove-PSSession $session
} else {
    echo "Server is unreachable"
}

Invoke-Command : A positional parameter cannot be found that accepts argument '-'.
At C:\Users\Desktop\scrit.ps1:62 char:1
+ Invoke-Command -Session $session -ArgumentList $opt -ScriptBlock $choice -
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidArgument: (:) [Invoke-Command], ParameterBindingException
    + FullyQualifiedErrorId : PositionalParameterNotFound,Microsoft.PowerShell.Commands.InvokeCommandCommand