用vb.net进行条形码扫描

Question

I am doing on 1 desktop application . I want to add barcode reading facility in this. In my app all products would have barcodes in their price tags. I will use some bar code scanner for scanning. but i am having no ides about all these. can anybody give apme sample code or some reference for this?

Answer 1

Most available barcode scanners emulate a keyboard. They come with configuration barcodes that let you configure it to do different things, such as include a carriage return at the end of the code once it scans. So, once you scan a code, it will appear on the screen as if it was typed out (if, for example, a textbox has focus).

Answer 2

For COM over USB you need the COM port number (look in your device manager), lets say COM15 Using VB.net use the System.IO.Ports.SerialPort class:

Dim comPort As New SerialPort("COM15") 'New com port'
Dim terminatingChar As Char = Chr(10) 'Terminate at vbLF (new line)'

comPort.BaudRate = 9600 '9600 baud speed'
comPort.Encoding = Encoding.ASCII 'Decode the bytes via ASCII code'

comPort.Open() 'Open the port'

Dim myBarcode as String = "" 'Current barcode is empty'

While True'Read chars until the terminating char appears'
    Dim tempChar as Char = Convert.ToChar(comPort.ReadChar()) 'Read a char'
    If tempChar = terminatingChar Then Exit While 'If its the terminating char, exit the loop'
    myBarcode = myBarcode & tempChar 'If not append it to the barcode string'
End While

comPort.Close() '(!) Close the port'

Console.WriteLine(myBarcode.Trim()) 'Trim it and show it to the user'