Trying to create a function - vb.net

Question

So I'm trying to change this sub in to a function so that I can reference it and set a label.text as it's result, this is so I don't have to creating new subs to update different labels.
Dim drive As String = "C"
Dim disk As ManagementObject = _
New ManagementObject _
("win32_logicaldisk.deviceid=""" + drive + ":""")
disk.Get()
Dim serial As String = disk("VolumeSerialNumber").ToString()
Label1.Text = ("Serial: " & serial)
Can someone tell me how I can change this in to a function? I've tried declaring Serial as an empty String and then changing the last line to read:
Return serial = disk("VolumeSerialNumber").ToString()
At the moment this just sets Label1.Text to display "False", like I've set it as a Boolean or something?!
I'm learning functions at the moment, I'm trying to make things cleaner as up until now I've just been creating different subs to update labels etc...
I'm looking for some tips so I can try and get this myself.

Answer 1

It is really a simple refactoring operation.
Sub Main
Dim driveLetter = "X"
Try
Dim result = DriveSerialNumber(driveLetter)
Console.WriteLine(result)
Catch ex as Exception
Console.WriteLine("Error: drive " & driveLetter & ": " & ex.Message)
End Try
End Sub
Public Function DriveSerialNumber(drive as String) As String
Dim disk As ManagementObject = _
New ManagementObject _
("win32_logicaldisk.deviceid=""" + drive + ":""")
disk.Get()
return disk("VolumeSerialNumber").ToString()
End Function
However, be prepared to receive Exceptions if you pass an invalid drive letter