Searching with the FSO

You may be thinking "Great, so now I know how to write files. I could've figured that out myself." So you want more tough guy? Let's try building a search feature for your web site.

The key to building a search engine is recursion. If you don't know what recursion is, find out why it's cool. Basically, you write one piece of code that performs a search on the files in a directory, and then make that same code loop through all the subdirectories. Since we don't know ahead of time how many subdirectories there may be, we have to call this piece of code over and over again until we're through. Recursion in it's finest.

So let's build the search page. We'll assume that you've already built an HTML form for a user to input a search string.

Dim objFolder

Dim strSearchText

Dim objFSO



strSearchText = Request.Form("SearchText")  <-- The search string



' create the FSO and Folder objects

Set fso = Server.CreateObject("Scripting.FileSystemObject")

Set objFolder = objFSO.GetFolder(Server.MapPath("/"))



Search objFolder

The above code simple initializes variables and gets us started. The meat of the search is performed by the Search function, described below:

Function Search(objFolder)

  Dim objSubFolder



  'loop through every file in the current folder

  For Each objFile in objFolder.Files

    Set objTextStream = objFSO.OpenTextFile(objFile.Path,1) <-- For Reading



	'read the file's contents into a variable

	strFileContents = objTextStream.ReadAll



	'if the search string is in the file, then write a link

	' to the file

	If InStr(1, strFileContents, strSearchText, 1) then

	   Response.Write "<A HREF=""/" & objFile.Name & _

	   	""">" & objFile.Name & "</A><BR>"



	   bolFileFound = True

	End If



	objTextStream.Close



  Next



  'Here's the recursion part - for each

  ' subfolder in this directory, run the Search function again

  For Each objSubFolder in objFolder.SubFolders

	Search objSubFolder

  Next

End Function

The code above will run through every subdirectory of every folder under the initial folder that you specified, which in this case, would be the root web path, specified by "/". Then we simply open each file in the directory, see if the desired string is in that file and display a link to that file if the search string is found. Not bad, huh?

Note that as the number of files and subdirectories increases, so will the time it takes to run this search. It's recommended that if you need a heavy duty search feature, turn to something else, such as Microsoft's Index Server.

Permissions
The wonders of the File System Object
Content Management with the FSO