Access SerialPort by string name

[Bo2k]

Hello,

I have some SerialPorts components COM1 to COM10.
I have a list containing the names as strings "COM1", "COM2" ... "COM10"
I am trying to iterate the list and send data eg:

For i As Integer = 0 To myPorts.Count - 1
       myPorts(i).Write("TEXT")
Next

The error is 'Write' is not a member of 'String'

I found out that for other elements on the form i can use Me.Controls to access them with strings,
but Serial Ports does not appear in Me.Controls. How can it be done?

Thanks!

[paulg4ije]

I have never iterated through a list of COM ports like that. This is the basic serial port code I have used:

     Dim sp1 As New IO.Ports.SerialPort
        sp1.PortName = "COM1"
        sp1.Open()
        sp1.Write("Test")
        sp1.Close()

This might give you some ideas.

[Bo2k]

     Dim sp1 As New IO.Ports.SerialPort
        sp1.PortName = "COM1"
        sp1.Open()
        sp1.Write("Test")
        sp1.Close()

This might give you some ideas.[/QUOTE]

Thank you for your answer, i writed the same code 10 times instead of iterating, as a workaround,
but is there really no way to access 'sp1.Open()' from your example, with a variable or string like 'sp' & '1'.Open() instead ?

Thanks

[paulg4ije]

Try something like this:

        Dim ComPorts() As String = {"COM1", "COM3", "COM4", "COM5"}

        Dim sp1 As New IO.Ports.SerialPort

        For Each s As String In ComPorts
            sp1.PortName = s
            sp1.Open()
            sp1.Write("Test")
            sp1.Close()
        Next

I created an array containing the COM ports on my PC. I can't easily test that the data actually arrives at the intended port, but it runs without errors.

[Bo2k]

Yes. methods as String works, i need to acces the Object with a string, i have independent ports that needs to stay opened to receive data, its something like this:

Dim sp1 As New IO.Ports.SerialPort 'already configured as COM1
Dim sp2 As New IO.Ports.SerialPort 'already configured as COM2
Dim sp3 As New IO.Ports.SerialPort 'already configured as COM3
Dim sp4 As New IO.Ports.SerialPort 'already configured as COM4

Lets say i have an input 'Close port:' and user enters "3".

How to access the object sp3 by concatenating 'sp' and the user's input '3' ?
or even if user inputs the full name of the Object like 'sp3', it will be a String, how do we access then sp3.Close() ?

Ofc in this simple and intuitive example there are workarounds like:
If input = 1 Then sp1.Close()
If input = 2 Then sp2.Close()
If input = 3 Then sp3.Close()

But isnt there a method to access the object if we only know its name as a String?

[PlausiblyDamp]

You might want to consider something like a Dictionary https://learn.microsoft.com/en-us/do...2?view=net-9.0

You could do something like

Dim ports as new Dictionary(Of String, SerialPort)

Dim sp As New IO.Ports.SerialPort
sp.PortName = "COM1"

ports.Add("1", sp)

'To get port 1 use
Dim port = ports("1")
port.Open()
'etc

[OptionBase1]

The most basic way would be to use an Array and match the index with the port number.

[Bo2k]

The Dictionary method does indeed what i am looking for..

Thank you all !