Function Name	List Files
Category	File
Icon
Description	Gets a all the files in a directory that match a given pattern
Inputs	Path The directory that function will enumerate all the files within (optional) If it's not connected the value is read from the internal property "File Path".
Outputs	Filename A list of all the files in the "File Path" that match the "pattern". This is the full path to the file
Properties	File Path If the input connection point "FilePath" is not connected then this directory is the one enumerated. Pattern A standard DOS style pattern to filter files i.e. *.xml Recursive true/false if this is true then all the child directories are also searched.

Usage

The Data Mapper ListFiles function converts reads all the files matching the provided pattern. This is useful for reading multiple input files :

In the following example the filenames taken from the ListFiles component are fed into the XML Readers Filename input. So every filename that ListFiles returns is opened as an XML document:

If we have the following input files in the target folder

<?xml version="1.0" encoding="utf-8"?>
<!-- Created with Liquid XML Studio (https://www.liquid-technologies.com) -->
<bookstore xmlns="https://www.liquid-technologies.com/sample/bookstore">
 <book price="4.99" publicationdate="2008-10-20" ISBN="978-0747596837">
  <title>The Graveyard Book</title>
  <author>
   <first-name>Neil</first-name>
   <last-name>Gaiman</last-name>
  </author>
  <genre>Horror</genre>
 </book>
 <book price="21.99" publicationdate="2002-05-14" ISBN="0-596-00252-1">
  <title>XML Schemas</title>
  <author>
   <first-name>Eric</first-name>
   <last-name>van der Vlist</last-name>
  </author>
  <genre>Reference</genre>
 </book>
</bookstore>

<?xml version="1.0" encoding="utf-8"?>
<!-- Created with Liquid XML Studio (https://www.liquid-technologies.com) -->
<bookstore xmlns="https://www.liquid-technologies.com/sample/bookstore">
 <book price="5.99" publicationdate="1999-05-02" ISBN="0-945-16546-1">
  <title>The Portable Door</title>
  <author>
   <first-name>Tom</first-name>
   <last-name>Holt</last-name>
  </author>
  <genre>Fiction</genre>
 </book>
</bookstore>

The if the ListFiles function is configured with a pattern say "input*.xml" then the 2 files will be read into the XML Reader and passed onto the writer resulting in;

<bookstore xmlns="https://www.liquid-technologies.com/sample/bookstore">
  <book>
    <title>The Graveyard Book</title>
  </book>
  <book>
    <title>XML Schemas</title>
  </book>
  <book>
    <title>The Portable Door</title>
  </book>
</bookstore>

Properties

The ListFiles properties values can be edited using the Properties Window.

Example

A range of functions are provided for working with Uri's and Path's. The following example demonstrates how these can be used.

In the following example we have a directory c:\UriExamples\ that contains the files Bookstore.xsd, Input001.xml, Input002.xml & ResolvedUri.Output.xml.

In our transform we have configured "ListFiles" to operate on the directory "c:\UriExamples\" and use the pattern "Input*.xml"

As you can see the ListFiles component gets the full paths of all the files that match the pattern. These filenames are then fed into the various Uri functions and output into an XML writer.

The result of the transform is as follows

<FileProperties>
  <File>
    <FullFilename>C:\UriExamples\Input001.xml</FullFilename>
    <Filename>Input001.xml</Filename>
    <Extension>.xml</Extension>
    <Path>C:\UriExamples</Path>
    <AltFullFilename>C:\UriExamples\Backup\Input001.xml</AltFullFilename>
    <BackupFilename>C:\UriExamples\Input001.xml.bak</BackupFilename>
  </File>
  <File>
    <FullFilename>C:\UriExamples\Input002.xml</FullFilename>
    <Filename>Input002.xml</Filename>
    <Extension>.xml</Extension>
    <Path>C:\UriExamples</Path>
    <AltFullFilename>C:\UriExamples\Backup\Input002.xml</AltFullFilename>
    <BackupFilename>C:\UriExamples\Input002.xml.bak</BackupFilename>
  </File>
</FileProperties>

Let's examine the output in more detail

• FullFilename value is what's returned from the ListFiles component, note it's the full path to the file.
• Filename has come via the GetFilename function, which has stripped off the path leaving just the filename.
• Extension has come via the GetExtension function, which has left us with just the extension (note the leading . is preserved).
• Path has come via the GetDirectoryName, this strips the filename leaving just the path (note it's the whole path, not just he parent directory name).
• AltFullFilename demonstrates how alternative paths can be constructed, in this case we take the files path, add the directory name 'Backup' and re-add the filename.
• BackupFilename shows how the ResolveUri method can be used to build filenames based on an existing filename/path. We use the Concat function to append .bak onto the existing filename (giving us Input001.xml.bak), we then resolve this relative to the original file c:\UriExamples\Input001.xml.