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Accept only numbers in a text field

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  9 years ago

  by Developer Fusion Bot

  Developer Fusion Bot

  , United Kingdom

  Joined 2 years ago

  This thread is for discussions of Accept only numbers in a text field.

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  6 years ago

  by the_liberator

  the_liberator

  Upper Hutt, New Zealand, New Zealand

  Joined 6 years ago

  Keypress can also be used for this.
  

  
  

  Code:

  
  Private Sub Text1_KeyPress(KeyAscii as Integer)
   'Ignore negatives
   If KeyAscii = 45 then goto EndProc
   'If Key pressed is not numeric then make key Null
   If (KeyAscii < 48) or (Keyascii >57) then KeyAscii = 0
   Endproc:
  End Sub
  

  
  

  
  I use this myself.

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  5 years ago

  by mr_mellow

  O Melo

  US, Florida, United States

  Joined 5 years ago

  KeyPress event is the better way to test user input. However, it requires a more elaborate code for user input testing.
  

  
  This example shows a moving decimal point and toggling for negative sign. Notice that whenever the control's value is changed by the code, the cursor position as to be reset.
  

  
  Private Sub Text1_KeyPress(KeyAscii As Integer)
    KeyAscii = InputNum(Text1, KeyAscii)
  End Sub
  

  
  Function InputNum(txtBox As TextBox, KeyAscii As Integer) As Integer
    If KeyAscii <> 8 Then ' Skips if Backspace key was used
       If InStr("01234567.-", Chr(KeyAscii)) = 0 Then
          KeyAscii = 0 ' Cancels user input
       ElseIf Chr(KeyAscii) = "." And InStr(Text1, ".") <> 0 Then
          a = Text1.SelStart
          b = InStr(Text1, ".")
          If a = b Or a + 1 = b Then ' there one already there
             KeyAscii = 0
          ElseIf a + 1 < b Then ' fiddle with "move" the decimal point
             Text1 = Left(Text1, b - 1) + Mid(Text1, b + 1)
             Text1.SelStart = a
          Else
             Text1 = Left(Text1, b - 1) + Mid(Text1, b + 1)
             Text1.SelStart = a - 1
          End If
       ElseIf Chr(KeyAscii) = "-" Then ' make/toggle the negative"
          a = Text1.SelStart
          KeyAscii = 0
          If InStr(Text1, "-") = 0 Then
             Text1 = "-" & Text1
             a = a + 1
          Else
             Text1 = Mid(Text1, 2)
             a = a - 1
          End If
          Text1.SelStart = a
       End If
    End If
    InputNum = KeyAscii
  End Function
  

  
  

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• • Reply

  3 years ago

  by Xenophanes

  Xenophanes

  Flanders, Belgium, Belgium

  Joined 3 years ago

  Public Function CheckNumeric (strTest As String) As String
  

  
  Dim I%
  

  
  On Error GoTo NotNumeric
  I% = strTest
  CheckNumeric = strTest
  Exit Function
  

  
  NotNumeric:
  CheckNumeric= Left$(strTest, Len(strTest) - 1)
  

  
  End Function
  

  
  Add this code to a TextBox's Change event:
  

  
  Text1.Text = CheckNumeric(Text1.Text)

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• • Reply

  1 year ago

  by chandra219

  chandra219

  , United States

  Joined 1 year ago

  Limit input in textbox that allows only digits, backspaces and one decimal point to be entered .

  Method 1 using keypress event:
  Private sub Text1_KeyPress(KeyAscii As Integer)
      Const Numbers$ = "0123456789."      'Permitted values in Textbox
      
      If KeyAscii <> 8 Then                          'Ascii for BackSpace 8
          If InStr(Numbers, Chr(KeyAscii)) = 0 Then    'If false, keypressed is suppressed
              MsgBox "error"
              KeyAscii = 0
              Exit Sub
          end If
      end If
     
  End Sub
  ------------------------------
  Method 2 using function-call:
  Function LimitTextInput(source) as String
      Const Numbers$ = "0123456789."
     If source <> 8 Then  'backspace is 8
          If InStr(Numbers, Chr(source)) = 0 Then
              LimitTextInput = 0
              exit Function
          end If
      end If
      LimitTextInput = source
     End Function
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

  Private Sub Text1_KeyPress(KeyAscii As Integer)
   KeyAscii = LimitTextInput(KeyAscii)   'Calling LimitTextInput function
  End Sub
  ------------------------------
  Method 3 simple keypress event:
  Private sub Text1_KeyPress(KeyAscii As Integer)
   If KeyAscii > 65 And KeyAscii < 123 Then
      KeyAscii = 0
      End If
  End if
  -------------------------------
  
  
  
  
  
  
  
  
  
  

  Method 4 using Validate event:

  Private Sub Text1_Validate(Cancel As Boolean)

  Cancel = IIF(Not IsNumeric(Text1), True, False)

  If Cancel then

  Msgbox "Enter Numeric Value only!", VbInformation, "Entry Error"

  With Text1

     . text = " "

     .SetFocus

  End With

  End if

  End Sub
  In this event, the user can not exit textbox unless inputting Numericvalue and also all other controls in the Form will be disabled.
  

  Method 4 One More Example

  Private Sub Text1_Validate(Cancel As Boolean)
  Cancel = Not IsDate(Text1.Text) Or Text1.Text <> Format(Text1.Text, "hh:mm:ss")
  

  If Cancel Then
  With lblSetTime
      .Caption = "Set Time in 24hr Format!"
      .ForeColor = vbRed
  End With
    Text1.Text = ""
    Text1.SetFocus
    CmdStart.Enabled = False
  Else
    CmdStart.Enabled = True
  
  
  
  
  
  
  
  
  

  End If
  End Sub
  

  In the above example, user is forced to enter time in "hh:mm:ss" format only for use in setting Alarm Time. Entries of anything else will be curbed by Validate event. If input is in "hh:mm:ss" format, then only the CmdStartButton will be enabled to permit user to click it.

  __________________________________End__________________________________

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