All programmers?especially database programmers?require a function that replaces all occurrences of one substring with another string. For example, they need to replace the single quotes in strings passed to an Oracle database with two single quotes.
Using recursion in this algorithm limits its usefulness slightly below that of VB6s native Replace function, as the time required increases greatly in relation to the length of the searched string:
Public Function strReplace(ByVal strString As _ String, ByVal strToBeReplaced As String, ByVal _ strReplacement As String, Optional ByVal _ intStartPosition As Integer = 1) As String Dim strNewString As String Dim intPosition As Integer On Error GoTo ErrorHandler ' intStartPosition will be one initially intPosition = InStr(intStartPosition, _ strString, strToBeReplaced) If intPosition = 0 Then ' Nothing more to do so return final string strReplace = strString Else strNewString = Left$(strString, intPosition _ - 1) & strReplacement & Mid$(strString, _ intPosition + Len(strToBeReplaced)) ' Recursively call strReplace until there are ' no more occurrences of the string to be ' replaced in the string passed in. We now only want ' to process the remaining unprocessed part of the ' string so we pass a start position. strReplace = strReplace(strNewString, _ strToBeReplaced, strReplacement, _ intPosition + Len(strReplacement)) End IfExit FunctionErrorHandler: ' Place error handler code hereEnd Function
