Imports System
Public Class Program
Friend Shared Function addToEmptyStr(ByVal pad As String, ByVal len As Integer) As String
Dim str As String = ""
While str.Length < len
str += pad
End While
Return str
End Function
Friend Shared Function addLeadingZero(ByVal str1 As String, ByVal str2 As String) As String
Dim len1 As Integer = str1.Length
Dim len2 As Integer = str2.Length
Dim strToPad As String = ""
Dim diff As Integer = Math.Abs(len1 - len2)
If diff > 0 Then
strToPad = addToEmptyStr("0", diff)
If len1 > len2 Then
strToPad += str2
Else
strToPad += str1
End If
End If
Return strToPad
End Function
Public Shared Sub Main(ByVal args As String())
Dim str1 As String = "123"
Dim str2 As String = "8976753"
If str1.Length > str2.Length Then
str2 = addLeadingZero(str1, str2)
Else
str1 = addLeadingZero(str1, str2)
End If
Console.WriteLine(str1)
Console.WriteLine(str2)
End Sub
End Class
' run:
'
' 0000123
' 8976753
'