Validate a TextBox before the _Change event is fired

I've got a form that has 3 TextBox controls on it: stock code, quantity, certificate number. The stock code TextBox is set to focus automatically when the form is loaded.

I've also attached a bar code scanner to my PC, as the user wants to be able to either scan a bar code to populate the TextBox, or manually type the data in.

The labels being scanned contain two bar codes. One is a certificate number and the other a stock code.

The stock bar code has a prefix of "SBC/", whilst a certificate bar code is prefixed with "C/".

When the user scans a bar code, if the TextBox in focus is the stock code TextBox, then I want to run a check as below.

Private Sub txtStockCode_Change()



On Error GoTo errError1



If Len(txtStockCode.Text) >= 5 Then

    If bChangeCode Then

        If Left(txtStockCode.Text, 2) = "C/" Then

            msgbox "You have scanned the certificate barcode; please scan the stock barcode."

            txtStockCode.Text = ""

        Else

            bChangeCode = False

            txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

            txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

        End If

    End If

End If



Exit Sub

Let's say the focus is currently on the stock code TextBox.

If the stock bar code is scanned, the following should happen:

Stock code length is greater than 5

Left 5 characters do not = "C/", so correct code has been scanned

TextBox text value is updated to remove all * and the prefix of "SBC/"

E.g. "SBC/A12-TR0*" becomes "A12-TRO"

and

Certificate number length is greater than 5

Left 5 characters do = "C/", so incorrect code has been scanned

MsgBox to user

TextBox value is reset to ""

However, no matter which code is scanned into the stock code TextBox, the value is never validated.

E.g. "SBC/A12-TR0*" remains as "SBC/A12-TR0*" and "C/29760" remains as "C/29760"

As the validation code is the same in the certificate TextBox, the same pattern is repeated vice versa.

Why are my values not updating, or how can I validate the input before the _Change is fired?

EDIT

I've now changed my code to

Private Sub txtStockCode_Change



   If txtStockCode.Text <> "" Then

      txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

      txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

   End If



End Sub

But it still displays the prefix of SBC/, yet is removing the two * characters (at the start and end of the barcode as is required for the scanner to read it as a barcode)

edited Nov 22 '18 at 13:03

asked Nov 20 '18 at 13:00

David

1,55221536

In your code, it looks like you are trying to remove the wrong prefix.
– Brian M Stafford
Nov 20 '18 at 13:16

@BrianMStafford oops, typo. Corrected.
– David
Nov 20 '18 at 14:20

Somewhere else in code have you set bChangeCode to True?
– Brian M Stafford
Nov 20 '18 at 14:39

1

The issue is because the Change event is firing once for every character of the bar code. The bChangeCode gets set to False and short-circuits your logic.
– Brian M Stafford
Nov 20 '18 at 15:18

1

I would expect to see that behavior with your existing code. You may have better luck moving the logic to the Validate event, though this would require programming your scanner to append a Tab key.
– Brian M Stafford
Nov 20 '18 at 16:12

|
show 2 more comments

I've got a form that has 3 TextBox controls on it: stock code, quantity, certificate number. The stock code TextBox is set to focus automatically when the form is loaded.

I've also attached a bar code scanner to my PC, as the user wants to be able to either scan a bar code to populate the TextBox, or manually type the data in.

The labels being scanned contain two bar codes. One is a certificate number and the other a stock code.

The stock bar code has a prefix of "SBC/", whilst a certificate bar code is prefixed with "C/".

When the user scans a bar code, if the TextBox in focus is the stock code TextBox, then I want to run a check as below.

Private Sub txtStockCode_Change()



On Error GoTo errError1



If Len(txtStockCode.Text) >= 5 Then

    If bChangeCode Then

        If Left(txtStockCode.Text, 2) = "C/" Then

            msgbox "You have scanned the certificate barcode; please scan the stock barcode."

            txtStockCode.Text = ""

        Else

            bChangeCode = False

            txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

            txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

        End If

    End If

End If



Exit Sub

Let's say the focus is currently on the stock code TextBox.

If the stock bar code is scanned, the following should happen:

Stock code length is greater than 5

Left 5 characters do not = "C/", so correct code has been scanned

TextBox text value is updated to remove all * and the prefix of "SBC/"

E.g. "SBC/A12-TR0*" becomes "A12-TRO"

and

Certificate number length is greater than 5

Left 5 characters do = "C/", so incorrect code has been scanned

MsgBox to user

TextBox value is reset to ""

However, no matter which code is scanned into the stock code TextBox, the value is never validated.

E.g. "SBC/A12-TR0*" remains as "SBC/A12-TR0*" and "C/29760" remains as "C/29760"

As the validation code is the same in the certificate TextBox, the same pattern is repeated vice versa.

Why are my values not updating, or how can I validate the input before the _Change is fired?

EDIT

I've now changed my code to

Private Sub txtStockCode_Change



   If txtStockCode.Text <> "" Then

      txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

      txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

   End If



End Sub

But it still displays the prefix of SBC/, yet is removing the two * characters (at the start and end of the barcode as is required for the scanner to read it as a barcode)

edited Nov 22 '18 at 13:03

asked Nov 20 '18 at 13:00

David

1,55221536

In your code, it looks like you are trying to remove the wrong prefix.
– Brian M Stafford
Nov 20 '18 at 13:16

@BrianMStafford oops, typo. Corrected.
– David
Nov 20 '18 at 14:20

Somewhere else in code have you set bChangeCode to True?
– Brian M Stafford
Nov 20 '18 at 14:39

1

The issue is because the Change event is firing once for every character of the bar code. The bChangeCode gets set to False and short-circuits your logic.
– Brian M Stafford
Nov 20 '18 at 15:18

1

I would expect to see that behavior with your existing code. You may have better luck moving the logic to the Validate event, though this would require programming your scanner to append a Tab key.
– Brian M Stafford
Nov 20 '18 at 16:12

|
show 2 more comments

I've got a form that has 3 TextBox controls on it: stock code, quantity, certificate number. The stock code TextBox is set to focus automatically when the form is loaded.

I've also attached a bar code scanner to my PC, as the user wants to be able to either scan a bar code to populate the TextBox, or manually type the data in.

The labels being scanned contain two bar codes. One is a certificate number and the other a stock code.

The stock bar code has a prefix of "SBC/", whilst a certificate bar code is prefixed with "C/".

When the user scans a bar code, if the TextBox in focus is the stock code TextBox, then I want to run a check as below.

Private Sub txtStockCode_Change()



On Error GoTo errError1



If Len(txtStockCode.Text) >= 5 Then

    If bChangeCode Then

        If Left(txtStockCode.Text, 2) = "C/" Then

            msgbox "You have scanned the certificate barcode; please scan the stock barcode."

            txtStockCode.Text = ""

        Else

            bChangeCode = False

            txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

            txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

        End If

    End If

End If



Exit Sub

Let's say the focus is currently on the stock code TextBox.

If the stock bar code is scanned, the following should happen:

Stock code length is greater than 5

Left 5 characters do not = "C/", so correct code has been scanned

TextBox text value is updated to remove all * and the prefix of "SBC/"

E.g. "SBC/A12-TR0*" becomes "A12-TRO"

and

Certificate number length is greater than 5

Left 5 characters do = "C/", so incorrect code has been scanned

MsgBox to user

TextBox value is reset to ""

However, no matter which code is scanned into the stock code TextBox, the value is never validated.

E.g. "SBC/A12-TR0*" remains as "SBC/A12-TR0*" and "C/29760" remains as "C/29760"

As the validation code is the same in the certificate TextBox, the same pattern is repeated vice versa.

Why are my values not updating, or how can I validate the input before the _Change is fired?

EDIT

I've now changed my code to

Private Sub txtStockCode_Change



   If txtStockCode.Text <> "" Then

      txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

      txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

   End If



End Sub

But it still displays the prefix of SBC/, yet is removing the two * characters (at the start and end of the barcode as is required for the scanner to read it as a barcode)

edited Nov 22 '18 at 13:03

asked Nov 20 '18 at 13:00

David

1,55221536

I've got a form that has 3 TextBox controls on it: stock code, quantity, certificate number. The stock code TextBox is set to focus automatically when the form is loaded.

I've also attached a bar code scanner to my PC, as the user wants to be able to either scan a bar code to populate the TextBox, or manually type the data in.

The labels being scanned contain two bar codes. One is a certificate number and the other a stock code.

The stock bar code has a prefix of "SBC/", whilst a certificate bar code is prefixed with "C/".

When the user scans a bar code, if the TextBox in focus is the stock code TextBox, then I want to run a check as below.

Private Sub txtStockCode_Change()



On Error GoTo errError1



If Len(txtStockCode.Text) >= 5 Then

    If bChangeCode Then

        If Left(txtStockCode.Text, 2) = "C/" Then

            msgbox "You have scanned the certificate barcode; please scan the stock barcode."

            txtStockCode.Text = ""

        Else

            bChangeCode = False

            txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

            txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

        End If

    End If

End If



Exit Sub

Let's say the focus is currently on the stock code TextBox.

If the stock bar code is scanned, the following should happen:

Stock code length is greater than 5

Left 5 characters do not = "C/", so correct code has been scanned

TextBox text value is updated to remove all * and the prefix of "SBC/"

E.g. "SBC/A12-TR0*" becomes "A12-TRO"

and

Certificate number length is greater than 5

Left 5 characters do = "C/", so incorrect code has been scanned

MsgBox to user

TextBox value is reset to ""

However, no matter which code is scanned into the stock code TextBox, the value is never validated.

E.g. "SBC/A12-TR0*" remains as "SBC/A12-TR0*" and "C/29760" remains as "C/29760"

As the validation code is the same in the certificate TextBox, the same pattern is repeated vice versa.

Why are my values not updating, or how can I validate the input before the _Change is fired?

EDIT

I've now changed my code to

Private Sub txtStockCode_Change



   If txtStockCode.Text <> "" Then

      txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

      txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

   End If



End Sub

But it still displays the prefix of SBC/, yet is removing the two * characters (at the start and end of the barcode as is required for the scanner to read it as a barcode)

string validation textbox vb6

edited Nov 22 '18 at 13:03

asked Nov 20 '18 at 13:00

David

1,55221536

edited Nov 22 '18 at 13:03

asked Nov 20 '18 at 13:00

David

1,55221536

edited Nov 22 '18 at 13:03

asked Nov 20 '18 at 13:00

David

1,55221536

asked Nov 20 '18 at 13:00

David

1,55221536

asked Nov 20 '18 at 13:00

David

1,55221536

In your code, it looks like you are trying to remove the wrong prefix.
– Brian M Stafford
Nov 20 '18 at 13:16

@BrianMStafford oops, typo. Corrected.
– David
Nov 20 '18 at 14:20

Somewhere else in code have you set bChangeCode to True?
– Brian M Stafford
Nov 20 '18 at 14:39

1

The issue is because the Change event is firing once for every character of the bar code. The bChangeCode gets set to False and short-circuits your logic.
– Brian M Stafford
Nov 20 '18 at 15:18

1

I would expect to see that behavior with your existing code. You may have better luck moving the logic to the Validate event, though this would require programming your scanner to append a Tab key.
– Brian M Stafford
Nov 20 '18 at 16:12

|
show 2 more comments

In your code, it looks like you are trying to remove the wrong prefix.
– Brian M Stafford
Nov 20 '18 at 13:16

@BrianMStafford oops, typo. Corrected.
– David
Nov 20 '18 at 14:20

Somewhere else in code have you set bChangeCode to True?
– Brian M Stafford
Nov 20 '18 at 14:39

1

The issue is because the Change event is firing once for every character of the bar code. The bChangeCode gets set to False and short-circuits your logic.
– Brian M Stafford
Nov 20 '18 at 15:18

1

I would expect to see that behavior with your existing code. You may have better luck moving the logic to the Validate event, though this would require programming your scanner to append a Tab key.
– Brian M Stafford
Nov 20 '18 at 16:12

In your code, it looks like you are trying to remove the wrong prefix.
– Brian M Stafford
Nov 20 '18 at 13:16

@BrianMStafford oops, typo. Corrected.
– David
Nov 20 '18 at 14:20

Somewhere else in code have you set bChangeCode to True?
– Brian M Stafford
Nov 20 '18 at 14:39

The issue is because the Change event is firing once for every character of the bar code. The bChangeCode gets set to False and short-circuits your logic.
– Brian M Stafford
Nov 20 '18 at 15:18

I would expect to see that behavior with your existing code. You may have better luck moving the logic to the Validate event, though this would require programming your scanner to append a Tab key.
– Brian M Stafford
Nov 20 '18 at 16:12

|
show 2 more comments

1 Answer
1

active

oldest

votes

You could try to set the barcode reader to return Enter key at the end of the scanned barcode and then use the Keypress event to check it and make your changes.

Sub txtStockCode_KeyPress(KeyAscii As Integer)

    If KeyAscii = vbKeyReturn Then

        If Len(txtStockCode.Text) >= 5 Then

            If bChangeCode Then

                If Left(txtStockCode.Text, 2) = "C/" Then

                    msgbox "You have scanned the certificate barcode; please scan the stock barcode."

                    txtStockCode.Text = ""

                Else

                    bChangeCode = False

                    txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

                    txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

                End If

            End If

        End If        

    End If

End Sub

answered Dec 3 '18 at 0:31

TufanDsl

add a comment |

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1 Answer
1

active

oldest

votes

1 Answer
1

active

oldest

votes

You could try to set the barcode reader to return Enter key at the end of the scanned barcode and then use the Keypress event to check it and make your changes.

Sub txtStockCode_KeyPress(KeyAscii As Integer)

    If KeyAscii = vbKeyReturn Then

        If Len(txtStockCode.Text) >= 5 Then

            If bChangeCode Then

                If Left(txtStockCode.Text, 2) = "C/" Then

                    msgbox "You have scanned the certificate barcode; please scan the stock barcode."

                    txtStockCode.Text = ""

                Else

                    bChangeCode = False

                    txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

                    txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

                End If

            End If

        End If        

    End If

End Sub

answered Dec 3 '18 at 0:31

TufanDsl

add a comment |

You could try to set the barcode reader to return Enter key at the end of the scanned barcode and then use the Keypress event to check it and make your changes.

Sub txtStockCode_KeyPress(KeyAscii As Integer)

    If KeyAscii = vbKeyReturn Then

        If Len(txtStockCode.Text) >= 5 Then

            If bChangeCode Then

                If Left(txtStockCode.Text, 2) = "C/" Then

                    msgbox "You have scanned the certificate barcode; please scan the stock barcode."

                    txtStockCode.Text = ""

                Else

                    bChangeCode = False

                    txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

                    txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

                End If

            End If

        End If        

    End If

End Sub

answered Dec 3 '18 at 0:31

TufanDsl

add a comment |

You could try to set the barcode reader to return Enter key at the end of the scanned barcode and then use the Keypress event to check it and make your changes.

Sub txtStockCode_KeyPress(KeyAscii As Integer)

    If KeyAscii = vbKeyReturn Then

        If Len(txtStockCode.Text) >= 5 Then

            If bChangeCode Then

                If Left(txtStockCode.Text, 2) = "C/" Then

                    msgbox "You have scanned the certificate barcode; please scan the stock barcode."

                    txtStockCode.Text = ""

                Else

                    bChangeCode = False

                    txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

                    txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

                End If

            End If

        End If        

    End If

End Sub

answered Dec 3 '18 at 0:31

TufanDsl

You could try to set the barcode reader to return Enter key at the end of the scanned barcode and then use the Keypress event to check it and make your changes.

Sub txtStockCode_KeyPress(KeyAscii As Integer)

    If KeyAscii = vbKeyReturn Then

        If Len(txtStockCode.Text) >= 5 Then

            If bChangeCode Then

                If Left(txtStockCode.Text, 2) = "C/" Then

                    msgbox "You have scanned the certificate barcode; please scan the stock barcode."

                    txtStockCode.Text = ""

                Else

                    bChangeCode = False

                    txtStockCode.Text = Replace(txtStockCode.Text, "SBC/", "")

                    txtStockCode.Text = Replace(txtStockCode.Text, "*", "")

                End If

            End If

        End If        

    End If

End Sub

answered Dec 3 '18 at 0:31

TufanDsl

answered Dec 3 '18 at 0:31

TufanDsl

answered Dec 3 '18 at 0:31

TufanDsl

answered Dec 3 '18 at 0:31

TufanDsl

add a comment |

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