Try/Catch block does not actually execute the get-eventlog cmdlet

For some reason, when I try to use the security option, it does not actually execute the get-eventlog cmdlet, but writes it to the screen as though it were quoted. The other logs work without the try catch block, but whenever I set them up with the try catch block, they still function as though the cmdlet were quoted.

$eventlogname = Read-Host "Which event log category do wish to view? Enter Application, Security, Setup, System, or Forwarded events"
$lognumber = Read-Host "Enter the number of logs you wish to retrieve"

switch 
    ($eventlogname)
{
     Security {
            $logseverity = Read-Host "What event severity do you wish to view? Enter Critical, Warning, Error, FailureAudit, SuccessAudit, or Information"
            $computernameeventlog = Read-Host "Please enter the hostname to query"

            if ($computernameeventlog -eq "localhost" )
            {
            try
                {
                    {
                    Get-EventLog -logname $eventlogname -EntryType $logseverity -Newest $lognumber -ErrorAction SilentlyContinue
                    }


                            }
                            catch [System.IO.IOException]
                            {
                                Write-Host "The hostname was incorrect or not available."
                            }
                            catch [System.InvalidOperationException]
                            {
                                Write-Host "The event log does not exist"
                            }
                    }
             else
                {

             try{
                    {
                        Get-EventLog -logname $eventlogname -EntryType $logseverity -ComputerName $computernameeventlog -Newest $lognumber -ErrorAction SilentlyContinue 
                    }
                        }
                            catch [System.IO.IOException]
                            {
                                Write-Host "The hostname was incorrect or not available."
                            }
                            catch [System.InvalidOperationException]
                            {
                                Write-Host "The event log does not exist"
                            }
                    }
                }

     "Forwarded events"
     {
        $computernamewinevent = Read-Host "Please enter the hostname to query"
        $logseverity = Read-Host "What event severity do you wish to view? Enter Critical, Warning, Error or Information"
        if ($computernamewinevent -eq "localhost")
        {
            Get-WinEvent -logname forwardedevents -MaxEvents $lognumber | where {$_.leveldisplayname -contains $logseverity}
        }
        else
        {
            Get-WinEvent -logname forwardedevents -MaxEvents $lognumber -ComputerName $computername | where {$_.leveldisplayname -contains $logseverity}
        }
    }
    default
    {
    $logseverity = Read-Host "What event severity do you wish to view? Enter Critical, Warning, Error or Information"
    $computernameeventlog = Read-Host "Please enter the hostname to query"

    if ($computernameeventlog -eq "localhost" )

        {
            Get-EventLog -logname $eventlogname -EntryType $logseverity -Newest $lognumber 
        }



    else
        {
            Get-EventLog -logname $eventlogname -EntryType $logseverity -ComputerName $computernameeventlog -Newest $lognumber
        }
}
}

In your code you have surrounded the command with brackets ({ }) such as this:

{
Get-EventLog -logname $eventlogname -EntryType $logseverity -ComputerName $computernameeventlog -Newest $lognumber -ErrorAction SilentlyContinue 
}

This will produce a script block, which will not execute but output as a string. What you want is remove the brackets.