for loop question

[lezawang]

Hi
I made a spelling mistake in the code below but still working fine.
the currentpostion in the loop

 For x = currentpostion To Len(phrase)

is wrong spelling. I stepped in the code and it is always 0. However, the code worked fine.
Why is that? Thank you

Sub onlynumber()
    Dim phrase As String
    Dim lenght As Integer
    Dim currentpostion As Integer
    Dim temp As String
    currentposition = 1
    Dim x As Integer
    
    phrase = InputBox("enter string")
    For x = currentpostion To Len(phrase)
        If (IsNumeric(Mid(phrase, currentposition, 1))) = True Then
        temp = temp & Mid(phrase, currentposition, 1)
        End If
        currentposition = currentposition + 1
    Next x
    MsgBox (temp)
End Sub

 

[Joe4]

Because you have not forced yourself to declare all variables by using "Option Explicit". So it just sees it as a different, undeclared variable.
If you turn that on, it will force to declare all variables before using them, and find errors like this.

See: https://www.excel-easy.com/vba/examples/option-explicit.html

 

[Joe4]

You actually do not need that variable at all in your code. It is redundant and unnecessary.
However, I would add an IF statement to make sure that the length of "phrase" is greater than 0 before going in to your loop, i.e.

Sub onlynumber()

    Dim phrase As String
    Dim temp As String
    Dim x As Integer
    
    phrase = InputBox("enter string")
    If Len(phrase) > 0 Then
        For x = 1 To Len(phrase)
            If (IsNumeric(Mid(phrase, x, 1))) = True Then
                 temp = temp & Mid(phrase, x, 1)
            End If
        Next x
        MsgBox (temp)
    End If
    
End Sub