Excel VBA Function: Date pattern recognition and replacement.

Excel-DateMultiFunction.vbs

Function DateMultiFunction(InputDate As String, InputType As Integer) As String
    ' 0: True or False
    ' 1: Replace date
    ' 2: Extract string

    ' Declare variables
    Dim regEx As New RegExp
    Dim strPattern As String
    
    '
    If InputType = 0 Or InputType = 1 Or InputType = 2 Then
        ' Date pattern
        strPattern = "[0-9]{2}[/][0-9]{2}[/][0-9]{4}"
        regEx.Pattern = strPattern
        
        ' Comparison function
        If InputType = 0 Then
            If regEx.Test(InputDate) Then DateMultiFunction = True Else DateMultiFunction = False
        End If
        
        ' Date replace function
        If InputType = 1 Then
            If regEx.Test(InputDate) Then DateMultiFunction = regEx.Replace(InputDate, Format(InputDate, "yyyymmdd"))
        End If
        
        ' String extract function
        If InputType = 2 Then
            regEx.Pattern = "[0-9]{2}[:][0-9]{2}[:][0-9]{2}"
            If regEx.Test(InputDate) Then DateMultiFunction = regEx.Execute(InputDate)(0)
        End If
        
    Else
        DateMultiFunction = "Wrong InputType"
    End If
    
End Function