There is no function in ASP to count number of words in sentence or long string. Bellow is very simple function that count number of words and return that count.

< %
Function CountWords (StrValue)
  Dim iWords, mLengthWithSpaces, mLengthWithoutSpaces

  ' following line calculate the actual length of string
  mLengthWithSpaces = Len(StrValue)

  ' following line remove all spaces from string and then calculate the length of string
  mLengthWithoutSpaces = Len(Replace(StrValue, " ", ""))

  ' subtract length (without spaces) from actual string length
  iWords = mLengthWithSpaces - mLengthWithoutSpaces

  CountWords = iWords + 1
End Function

'example
Msg = "This is text string"
Response.Write CountWords(Msg)

'output will be 4
%>