HL7PlusFolderAnalyzer

*All example code is in Visual Basic.Net

'Where MyController is a HL7PlusController object

Dim oAnalyzer As HL7PlusFolderAnalyzer

oAnalyzer = MyController.NewHL7PlusFolderAnalyzer("C:\Hl7Data")

If IsNothing(oAnalyzer) Then

'An Error occurred

MessageBox.Show(MyController.LastError, "Error")

Return

End If

'A data table to hold our analysis results

Dim dtResult As DataTable

With oAnalyzer

'I want to look for 2 different file extensions

.AddFileExtension("hl7")

.AddFileExtension("txt")

'I don't want to see any 0 byte files

.IgnoreZeroByteFiles = True

'This is a shared folder so I want to make sure that I

'don't step on a file while it's being copied into my folder.

.MinimumFileAge = 2 'Files must be at least 2 seconds old to qualify

dtResult = .AnalyzeFolder()

If .IsError Then

MessageBox.Show(.LastError, "Analysis Error")

Return

End If

End With

'dtResult is now a data table with 5 columns

'--1) FILETITLE (String)

'--2) FILEEXTENSION (String)

'--3) FILEDATE (Date)

'--4) FILESIZE (Long)

'--5) PROCESSED (Boolean) Will be False

'--The Default View sort will be on FILEDATE AND FILETITLE

'--There will be NO NULL FIELD VALUES

If dtResult.Rows.Count = 0 Then

MessageBox.Show(oAnalyzer.FolderPath & " Contains no matching text files")

Return

End If

Dim dv As DataView = dtResult.DefaultView

Dim i As Integer

Dim fld As String = oAnalyzer.FolderPath 'This WILL have a trailing backslash

For i = 0 To dv.Count - 1

Dim s As String = fld & dv(i)("FILETITLE")

'....Code for each file

Property Name	Data Type	Description
FileExtensions	List(of String)	A .Net List of the file extensions used by the object when polling FolderPath. PROGRAMMING NOTE: The List returned here is a COPY of an internal list and you cannot use this property to add/remove file extensions. To add/remove file extensions see AddFileExtension() in Methods.
FolderPath	String	The Folder being analyzed (set when you create the object, see Implementation above).
FolderPathExists	Boolean	Indicates whether FolderPath exists or is visible to the object.
IgnoreHiddenFiles	Boolean	Default value is True. If True then files flagged as HIDDEN will not be returned when you call AnalyzeFolder().
IgnoreReadOnlyFiles	Boolean	Default value is False. If True then files flagged as READ-ONLY will not be returned when you call AnalyzeFolder().
IgnoreSystemFiles	Boolean	Default value is True. If True then files flagged as SYSTEM will not be returned when you call AnalyzeFolder().
IgnoreZeroByteFiles	Boolean	Default value is False. If True then files with 0 bytes will not be returned when you call AnalyzeFolder().
MinimumFileAge	Integer	The minimum age of files (in seconds) a file must be to be considered for retrieval operations. The Default value is 1. PROGRAMMING NOTE: If set to 60, when polling the folder any files LESS than or equal to 1 minute old will be IGNORED. This includes any files which might be dated in the future (files copied or created on other computers with a System Clock mismatch).
OperationCancelled	Boolean	Indicates whether the last analysis / retrieval operation was cancelled before completion.
ParentHL7Controller	HL7PlusController	The HL7PlusController used to create the file analyzer object (See Implementation above)
Tag	String	A general purpose String Tag value for your use.

Method:	AddFileExtension(strFileExtension)
Paramters:	1: strFileExtension (String) the file extension to add.
Return Value:	Boolean
Description:	Adds a single file extension (strFileExtension) to the internal list of file extensions to look for when polling the folder. If no file extensions are added then it will look for ALL files (.) PROGRAMMING NOTE: When calling this method strFileExtension must be ONLY the file extension, no wildcard characters or periods. If you want your folder analyzer to look for Ascii Text files you would call AddFileExtension("txt"). File extensions are NOT case sensitive.

Method:	AddFileExtensions(oListOfExtensions)
Paramters:	1: oListOfExtensions (List(of String)) A .Net List (of String) containing file extensions to look for.
Return Value:	Boolean
Description:	Adds multiple file extensionsto the internal list of file extensions to look for when polling the folder. If no file extensions are added then it will look for ALL files (.) PROGRAMMING NOTE: When calling this method each item in oListOfExtensions must follow the same rules as in AddFileExtension() above.

Method:	AnalyzeFolder()
Paramters:	None
Return Value:	System.Data.DataTable
Description:	Analyzes FolderPath and detects all files with a file extension matching FileExtensions that are at least MinimumFileAge seconds old (if MinimumFileAge is > 0) and returns a DataTable containing file information. See Implementation above for a breakdown of the structure of the DataTable.

Method:	ClearFileExtensions()
Paramters:	None
Return Value:	Boolean
Description:	Clears the internal list of file extensions to look for when polling FolderPath. If there are no file extensions the object will return all files (.)

Method:	CountAllFilesInFolder()
Paramters:	None
Return Value:	Long
Description:	Counts all files in FolderPath with file extensions that match FileExtensions. PROGRAMMING NOTE: When called this method DOES NOT take into account the age of the file using MinimumFileAge. So it is possible for this method to return a value > 0 and AnalyzeFolder() to return an empty DataTable.

Event:

Working (strMessage, blnCancel)

Paramters:

1: strMessage (String) A short message string describing what is being done by the object.

2: blnCancel (Boolean) Initial Value = False- Do you want to cancel the operation

Condition:

This event is fired frequently when AnalyzeFolder() is called. Set blnCancel to True to cancel the operation.

This object class uses our standard HL7PlusException Class interface for error handling wherever possible.

See the HL7PlusException Implementation Reference

Class Name:	HL7PlusFolderAnalyzer
HL7+ Category:	Restricted (Accessed through the HL7PlusController object)
Description:	Folder Poller object class for HL7 data files