WatchFolder() - updated on 2021-10-14

[yhtmn]

hi there, is it possible to trigger action after folder change happens? Or for example is it possible to trigger an action when .xls is added to watched folder?

[ahk7]

hi there, is it possible to trigger action after folder change happens? Or for example is it possible to trigger an action when .xls is added to watched folder?

That is the entire purpose of the function Example, note the values of what is what

Code: Select all

#Persistent
#SingleInstance, force
SetWorkingDir, %A_ScriptDir%

#include WatchFolder.ahk ; copy/download the code from the first post, save it as WatchFolder.ahk 

;     ReadDirectoryChangesW          msdn.microsoft.com/en-us/library/aa365465(v=vs.85).aspx
;     FILE_NOTIFY_CHANGE_FILE_NAME   = 1   (0x00000001) : Notify about renaming, creating, or deleting a file.
;     FILE_NOTIFY_CHANGE_DIR_NAME    = 2   (0x00000002) : Notify about creating or deleting a directory.
;     FILE_NOTIFY_CHANGE_ATTRIBUTES  = 4   (0x00000004) : Notify about attribute changes.
;     FILE_NOTIFY_CHANGE_SIZE        = 8   (0x00000008) : Notify about any file-size change.
;     FILE_NOTIFY_CHANGE_LAST_WRITE  = 16  (0x00000010) : Notify about any change to the last write-time of files.
;     FILE_NOTIFY_CHANGE_LAST_ACCESS = 32  (0x00000020) : Notify about any change to the last access time of files.
;     FILE_NOTIFY_CHANGE_CREATION    = 64  (0x00000040) : Notify about any change to the creation time of files.
;     FILE_NOTIFY_CHANGE_SECURITY    = 256 (0x00000100) : Notify about any security-descriptor change.
;     FILE_NOTIFY_INFORMATION        msdn.microsoft.com/en-us/library/aa364391(v=vs.85).aspx
;     FILE_ACTION_ADDED              = 1   (0x00000001) : The file was added to the directory.
;     FILE_ACTION_REMOVED            = 2   (0x00000002) : The file was removed from the directory.
;     FILE_ACTION_MODIFIED           = 3   (0x00000003) : The file was modified.
;     FILE_ACTION_RENAMED            = 4   (0x00000004) : The file was renamed (not defined by Microsoft).
;     FILE_ACTION_RENAMED_OLD_NAME   = 4   (0x00000004) : The file was renamed and this is the old name.
;     FILE_ACTION_RENAMED_NEW_NAME   = 5   (0x00000005) : The file was renamed and this is the new name.
;     GetOverlappedResult            msdn.microsoft.com/en-us/library/ms683209(v=vs.85).aspx
;     CreateFile                     msdn.microsoft.com/en-us/library/aa363858(v=vs.85).aspx
;     FILE_FLAG_BACKUP_SEMANTICS     = 0x02000000
;     FILE_FLAG_OVERLAPPED           = 0x40000000

WatchFolder("path-to-your-folder", "ReportFunction") ; change the path of course

ReportFunction(Directory, Changes)
	{
	 For Each, Change In Changes
		{
		 Action := Change.Action
		 Name := Change.Name
		 ; -------------------------------------------------------------------------------------------------------------------------
		 ; Action 1 (added) = File gets added in the watched folder
		 If (Action = 1) 
		 	{
			 If RegExMatch(name,"i)\.xlsx?$") check if we have an excel file (ending in xls or xlsx)
			 	{
			 	 ; if excel file do something
			 	 MsgBox % name
			 	}
		 	}
		}
	}

[dostroll]

Thank you just me for your wonderful function.
It works as expected, but there is one problem. I'd love to get some advice on how to resolve this if you'd like:)

WatchFolder is used to convert a RAR file with a specified filename with date to uncompressed ZIP.
The zip software I use generates a .tmp file with the same filename in the same directory as the file being processed.
This causes the unpacking process to be performed three times.

Create file
Pudding.rar → 1 Action
Pudding.tmp → 2 Action(but, Nothing happens because the file is in use.)
Pudding.zip → 3 Action(but, Unpacked, so nothing happens.)

Even if PAUSE is built in, it will be processed multiple times.

Code: Select all

If RegExMatch(name, "Humpty_Dumpty|Pudding|chocolate")
{
WatchFolder("**PAUSE", True)
<unpack code>
WatchFolder("**PAUSE", False)
}

Is there any good solution?

[just me]

Code: Select all

If RegExMatch(name, "(Humpty_Dumpty|Pudding|chocolate).*\.rar$") {
	<unpack code>
}

?

[dostroll]

Thanks for getting back to me so quickly!
It worked perfectly.
It was a regular expression problem, I understand.

[tester]

Just reporting that the function does not detect any changes for directories on a network drive in my environment, Windows 10 64bit with AutoHotkeyU64 1.1.34.03.

[tester]

@just me I'm wondering if you can implement the ability to accept class methods for the callback function like what SetTimer does.

Code: Select all

oWatchFolder := new TestWatchFolder(A_ScriptDir)
class TestWatchFolder {

    sPathDir := ""
    func := {}

    __New(sPathDir) {

        this.sPathDir := sPathDir
        this.func     := ObjBindMethod(this, "watch")
        WatchFolder(sPathDir, this.func, true)

    }

    watch(sPathFolder, oChanges) {
        ; do something
    }

}

From the manual of SetTimer,

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class SecondCounter {
    __New() {
        this.interval := 1000
        this.count := 0
        ; Tick() has an implicit parameter "this" which is a reference to
        ; the object, so we need to create a function which encapsulates
        ; "this" and the method to call:
        this.timer := ObjBindMethod(this, "Tick")
    }
    Start() {
        ; Known limitation: SetTimer requires a plain variable reference.
        timer := this.timer
        SetTimer % timer, % this.interval
        ToolTip % "Counter started"
    }
    ...
 

[Netmano]

I dont really know much of Autohotkey outside of Sendinput and sleep. I was able to put this together from reading this thread. Here is my code so far:

Code: Select all

#Persistent
#Include, <WatchFolder>
WatchFolder("C:\Users\...\Downloads", "ReportFunction", false, 1 | 2 | 4 | 8 |16 | 32 | 64 | 256)
Return
ReportFunction(Directory, Changes) { 
 For Each, Change In Changes {
       Action := Change.Action
       Name := Change.Name
	   If (Action = 3)
		 Run, Notepad
             Return
}
}
Esc::ExitApp

I am struggling with File modified action, Any autohotkey code I set to execute upon a file being modified is run twice. In the above example Run, Notepad is executed twice, so two notepad windows open. Its the same if I get a .Url link to open. It will be open twice too.

Any ideas what I could be doing wrong?

PS: Watchfolder function is saved in Documents\Autohotkey\Lib folder and I have made no changes to it, it is as I downloaded it.

[dostroll]

Only two files will be processed for more than two files.
Are there any best practices for loop processing to handle all files?

[just me]

@just me I'm wondering if you can implement the ability to accept class methods for the callback function like what SetTimer does.

@tester: I'm not interested in doing it, sorry.

I am struggling with File modified action, Any autohotkey code I set to execute upon a file being modified is run twice.

@Netmano: What kind of modifications do you do you specify to be watched?

Only two files will be processed for more than two files.

@dostroll: Show your code, please.

[dostroll]

I solved it by accident.
Sorry for the inconvenience...
It's because I typed "Return". (I don't understand why there is a problem with Return.)

Code: Select all

; Action 1 (added) = File gets added in the watched folder
If (vAction = 1)
{
	If RegExMatch(Name, "(chocolate|cocoa|sup).*\.(rar|cbz)$")
	{
		Sleep, 500
		Run, rename.exe "%vName%"
		tooltip_func("● Unzip complete", 950)
		; Return
	}

[Netmano]

@just me
Hey, thanks for getting back to me.
I want to be notified only if the files contents has been edited

[neogna2]

@just me On my PC WatchFolder() (both the v1 and v2 version) calls the UserFunc twice for each change, I think that's the issue @Netmano is reporting too. I tested with the WatchFolder_sample.ahk script.

[just me]

I want to be notified only if the files contents has been edited

Try to set the Watch parameter to 0x10 (FILE_NOTIFY_CHANGE_LAST_WRITE) in this case.

[neogna2]

8 second clip that shows the "calls the UserFunc twice for each change" issue
https://i.imgur.com/509vRk5.mp4

[just me]

@neogna2:
I cannot reproduce the behaviour here. I'm getting only one call for the UserFunc.

[neogna2]

@neogna2:
I cannot reproduce the behaviour here. I'm getting only one call for the UserFunc.

Hm, my PC runs Win10 (august 2022 updated) and I get the UserFunc called twice issue with v1 U32 and U64 (and v2.beta7 for v2 WatchFolder) and when using several different apps to trigger the file/folder change. Perhaps @Netmano (and others) can reply and say if they have exactly the same issue as in my clip above. In order to pin down if this is a WatchFolder code issue or more of a neogna2's PC issue.

[malcev]

https://devblogs.microsoft.com/oldnewthing/20140507-00/?p=1053
Possible solutions:
https://stackoverflow.com/questions/1764809/filesystemwatcher-changed-event-is-raised-twice

[neogna2]

Seems there's no perfect solution among those StackOverflow answers? Here's a quick attempt. If previous call was < 100 ms ago and if the file and type of change is the same as in the previous call then skip that item this call. Possible problem: these extra checks might slow things down or cause other problems if a ton of files are monitored with lots of changes frequently?

Code: Select all

MyUserFunc(Folder, Changes) {
   Static Actions := ["1 (added)", "2 (removed)", "3 (modified)", "4 (renamed)"]
   static PrevTickCount := 0
   static PrevChanges := []
   TickCount := A_TickCount
   GuiControl, -ReDraw, LV
   For Each, Change In Changes
   {
      if (TickCount - OldTickCount) < 100
         for Each, OldChange In OldChanges 
            if Change.Action = OldChange.Action && Change.Name = OldChange.Name
               Continue, 2
      LV_Modify(LV_Add("", TickCount, Folder, Actions[Change.Action], Change.Name, Change.IsDir, Change.OldName, ""), "Vis")
   }
   OldChanges := Changes
   OldTickCount := TickCount
   Loop, % LV_GetCount("Columns")
      LV_ModifyCol(A_Index, "AutoHdr")
   GuiControl, +Redraw, LV
}

[just me]

Hi @neogna2,

because I don't use Notepad++ I tested using Notepad. The UserFunc is called only once if you save the file with Notepad. When I tried the same with my favourite editor PSPad, then function was called twice here too. So the number of calls seems to depend on the application writing the file.