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copied!<p>There is a way to differentiate between keyboard and USB barcode reader </p> <p>You can depend on these facts:</p> <ol> <li>the code scanned by barcode reader in minmum 4 characters</li> <li>the code scanned by barcode reader ends with RETURN "ENTER"</li> <li>it take less than 50 mseconds to scan the hole barcode</li> </ol> <p>This is a simple form using VS2005 VB contains:</p> <ol> <li>textbox1</li> <li>textbox2</li> <li>textbox3</li> <li>Button1</li> <li>Timer1 "the time interval set to 50"ms"</li> </ol> <hr> <pre><code>Public Class Form1 Dim BarcodeStr As String = "" Dim IsBarcodeTaken As Boolean = False Dim Str As String = "" Dim str3 As String = "" Private Sub Form1_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown If Timer1.Enabled = False Then Str = TextBox1.Text str3 = TextBox3.Text End If End Sub Private Sub Form1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles Me.KeyPress If Timer1.Enabled = False Then Timer1.Enabled = True End If BarcodeStr = BarcodeStr & e.KeyChar If Asc(e.KeyChar) = 13 And Len(BarcodeStr) >= 4 Then IsBarcodeTaken = True TextBox2.Text = BarcodeStr End If End Sub Private Sub Form1_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyUp If IsBarcodeTaken = True Then TextBox1.Text = Str TextBox1.Select(Len(TextBox1.Text), 0) Str = "" TextBox3.Text = str3 TextBox3.Select(Len(TextBox3.Text), 0) str3 = "" End If End Sub Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick BarcodeStr = "" IsBarcodeTaken = False Timer1.Enabled = False End Sub Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click TextBox2.Text = "" End Sub End Class </code></pre>

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