How To Draw BarCode with Visual Basic 6

A barcode (also bar code) is a machine-readable representation of information (usually dark ink on a light background to create high and low reflectance which is converted to 1s and 0s).

Originally, barcodes stored data in the widths and spacings of printed parallel lines, but today they also come in patterns of dots, concentric circles, and text codes hidden within images. Barcodes can be read by optical scanners called barcode readers or scanned from an image by special software.

Barcodes are widely used to implement Auto ID Data Capture (AIDC) systems that improve the speed and accuracy of computer data entry. An advantage over other methods of AIDC is that it is less expensive to implement.

Making a simple barcode is not difficult at all, we just need to choose our favorite programming language, and use the simple algorithm to create it.

below is just a simple function to create a barcode, to use it you just need to call the function by send the parameters needed.

Call DrawBarcode(Text1, Picture1)
'Text1 is a component of TextBox and Picture1 is a component of PictureBox

And the function is :

Sub DrawBarcode(ByVal bc_string As String, obj As Object)

Dim xpos!
Dim Y1!
Dim Y2!
Dim dw%
Dim Th!
Dim tw
Dim new_string$
If bc_string = "" Then obj.Cls: Exit Sub

Dim bc(90) As String
bc(1) = "1 1221"

bc(2) = "1 1221"
bc(48) = "11 221"
bc(49) = "21 112"
bc(50) = "12 112"
bc(51) = "22 111"
bc(52) = "11 212"
bc(53) = "21 211"
bc(54) = "12 211"
bc(55) = "11 122"
bc(56) = "21 121"
bc(57) = "12 121"
bc(65) = "211 12"
bc(66) = "121 12"
bc(67) = "221 11"
bc(68) = "112 12"
bc(69) = "212 11"
bc(70) = "122 11"
bc(71) = "111 22"
bc(72) = "211 21"
bc(73) = "121 21"
bc(74) = "112 21"
bc(75) = "2111 2"
bc(76) = "1211 2"
bc(77) = "2211 1"
bc(78) = "1121 2"
bc(79) = "2121 1"
bc(80) = "1221 1"
bc(81) = "1112 2"
bc(82) = "2112 1"
bc(83) = "1212 1"
bc(84) = "1122 1"
bc(85) = "2 1112"
bc(86) = "1 2112"
bc(87) = "2 2111"
bc(88) = "1 1212"
bc(89) = "2 1211"
bc(90) = "1 2211"
bc(32) = "1 2121"
bc(35) = ""
bc(36) = "1 1 1 11"
bc(37) = "11 1 1 1"
bc(43) = "1 11 1 1"
bc(45) = "1 1122"
bc(47) = "1 1 11 1"
bc(46) = "2 1121"
bc(64) = ""
bc(42) = "1 1221"
bc_string = UCase(bc_string)
obj.ScaleMode = 3
obj.Cls
obj.Picture = Nothing
dw = CInt(obj.ScaleHeight / 40)
If dw < dw =" 1 tw = obj.TextWidth(bc_string)
new_string = Chr$(1) & bc_string & Chr$(2)
Y1 = obj.ScaleTop
Y2 = obj.ScaleTop + obj.ScaleHeight - 1.5 * Th
obj.Width = 1.1 * Len(new_string) * (15 * dw) * obj.Width / obj.ScaleWidth
xpos = obj.ScaleLeft
For n = 1 To Len(new_string)
c = Asc(Mid$(new_string, n, 1))
If c > 90 Then c = 0
bc_pattern$ = bc(c)
For i = 1 To Len(bc_pattern$)
Select Case Mid$(bc_pattern$, i, 1)
Case " "
obj.Line (xpos, Y1)-(xpos + 1 * dw, Y2), &HFFFFFF, BF
xpos = xpos + dw
Case "1"
obj.Line (xpos, Y1)-(xpos + 1 * dw, Y2), &HFFFFFF, BF
xpos = xpos + dw
obj.Line (xpos, Y1)-(xpos + 1 * dw, Y2), &H0&, BF
xpos = xpos + dw
Case "2"
obj.Line (xpos, Y1)-(xpos + 1 * dw, Y2), &HFFFFFF, BF
xpos = xpos + dw
obj.Line (xpos, Y1)-(xpos + 2 * dw, Y2), &H0&, BF
xpos = xpos + 2 * dw
End Select
Next
Next
obj.Line (xpos, Y1)-(xpos + 1 * dw, Y2), &HFFFFFF, BF
xpos = xpos + dw
obj.Width = (xpos + dw) * obj.Width / obj.ScaleWidth
obj.CurrentX = (obj.ScaleWidth - tw) / 2
obj.CurrentY = Y2 + 0.25 * Th
obj.Print bc_string

End Sub


I already use it and it works successfully.