Loop Files

Retrieves the specified files or folders, one at a time.

Loop Files FilePattern , Mode

Parameters

FilePattern

Type: String

The name of a single file or folder, or a wildcard pattern such as "C:\Temp\*.tmp". FilePattern is assumed to be in A_WorkingDir if an absolute path isn't specified.

Both asterisks and question marks are supported as wildcards. A match occurs when the pattern appears in either the file's long/normal name or its 8.3 short name.

If this parameter is a single file or folder (i.e. no wildcards) and Mode includes R, more than one match will be found if the specified file name appears in more than one of the folders being searched.

Mode

Type: String

An optional string containing zero or more of the following letters:

D: Include directories (folders).
F: Include files. If both F and D are omitted, files are included but not folders.
R: Recurse into subdirectories (subfolders). All subfolders will be recursed into, not just those whose names match FilePattern. If R is omitted, files and folders in subfolders are not included.

Special Variables Available Inside a File-Loop

The following variables exist within any file-loop. If an inner file-loop is enclosed by an outer file-loop, the innermost loop's file will take precedence:

A_LoopFileName The name of the file or folder currently retrieved (without the path).
A_LoopFileExt The file's extension (e.g. TXT, DOC, or EXE). The period (.) is not included.
A_LoopFilePath The path and name of the file/folder currently retrieved. If FilePattern contains a relative path rather than an absolute path, the path here will also be relative. In addition, any short (8.3) folder names in FilePattern will still be short (see next item to get the long version).
A_LoopFileFullPath This is different than A_LoopFilePath in the following ways: 1) It always contains the absolute/complete path of the file even if FilePattern contains a relative path; 2) Any short (8.3) folder names in FilePattern itself are converted to their long names; 3) Characters in FilePattern are converted to uppercase or lowercase to match the case stored in the file system. This is useful for converting file names -- such as those passed into a script as command line parameters -- to their exact path names as shown by Explorer.
A_LoopFileShortPath

The 8.3 short path and name of the file/folder currently retrieved. For example: C:\MYDOCU~1\ADDRES~1.txt. If FilePattern contains a relative path rather than an absolute path, the path here will also be relative.

To retrieve the complete 8.3 path and name for a single file or folder, specify its name for FilePattern as in this example:

Loop Files, "C:\My Documents\Address List.txt"
    ShortPathName := A_LoopFileShortPath

Note: This variable will be blank if the file does not have a short name, which can happen on systems where NtfsDisable8dot3NameCreation has been set in the registry. It will also be blank if FilePattern contains a relative path and the body of the loop uses SetWorkingDir to switch away from the working directory in effect for the loop itself.

A_LoopFileShortName The 8.3 short name, or alternate name of the file. If the file doesn't have one (due to the long name being shorter than 8.3 or perhaps because short-name generation is disabled on an NTFS file system), A_LoopFileName will be retrieved instead.
A_LoopFileDir The path of the directory in which A_LoopFileName resides. If FilePattern contains a relative path rather than an absolute path, the path here will also be relative. A root directory will not contain a trailing backslash. For example: C:
A_LoopFileTimeModified The time the file was last modified. Format YYYYMMDDHH24MISS.
A_LoopFileTimeCreated The time the file was created. Format YYYYMMDDHH24MISS.
A_LoopFileTimeAccessed The time the file was last accessed. Format YYYYMMDDHH24MISS.
A_LoopFileAttrib The attributes of the file currently retrieved.
A_LoopFileSize The size in bytes of the file currently retrieved. Files larger than 4 gigabytes are also supported.
A_LoopFileSizeKB The size in Kbytes of the file currently retrieved, rounded down to the nearest integer.
A_LoopFileSizeMB The size in Mbytes of the file currently retrieved, rounded down to the nearest integer.

Remarks

A file-loop is useful when you want to operate on a collection of files and/or folders, one at a time.

All matching files are retrieved, including hidden files. By contrast, OS features such as the DIR command omit hidden files by default. To avoid processing hidden, system, and/or read-only files, use something like the following inside the loop:

if A_LoopFileAttrib ~= "[HRS]"  ; Skip any file that is either H (Hidden), R (Read-only), or S (System). See ~= operator.
    continue  ; Skip this file and move on to the next one.

To retrieve files' relative paths instead of absolute paths during a recursive search, use SetWorkingDir to change to the base folder prior to the loop, and then omit the path from the Loop (e.g. Loop Files, "*.*", "R"). That will cause A_LoopFilePath to contain the file's path relative to the base folder.

A file-loop can disrupt itself if it creates or renames files or folders within its own purview. For example, if it renames files via FileMove or other means, each such file might be found twice: once as its old name and again as its new name. To work around this, rename the files only after creating a list of them. For example:

FileList := ""
Loop Files, "*.jpg"
    FileList .= A_LoopFileName "`n"
Loop Parse, FileList, "`n"
    FileMove A_LoopField, "renamed_" A_LoopField

Files in an NTFS file system are probably always retrieved in alphabetical order. Files in other file systems are retrieved in no particular order. To ensure a particular ordering, use the Sort function as shown in the Examples section below.

Files and folders with a complete path name longer than 259 characters are skipped over as though they do not exist. Such files are rare because normally, the operating system does not allow their creation.

See Loop for information about Blocks, Break, Continue, and the A_Index variable (which exists in every type of loop).

Related

Loop, Break, Continue, Blocks, SplitPath, FileSetAttrib, FileSetTime

Examples

#1

Loop Files, A_ProgramFiles "\*.txt", "R"  ; Recurse into subfolders.
{
    Result := MsgBox("Filename = " A_LoopFilePath "`n`nContinue?",, "y/n")
    if Result = "No"
        break
}

#2: Calculate the size of a folder, including the files in all its subfolders:

FolderSizeKB := 0
WhichFolder := DirSelect()  ; Ask the user to pick a folder.
Loop Files, WhichFolder "\*.*", "R"
    FolderSizeKB += A_LoopFileSizeKB
MsgBox "Size of " WhichFolder " is " FolderSizeKB " KB."

#3: Retrieve file names sorted by name (see next example to sort by date):

FileList := ""  ; Initialize to be blank.
Loop Files, "C:\*.*"
    FileList .= A_LoopFileName "`n"
FileList := Sort(FileList, "R")  ; The R option sorts in reverse order. See Sort for other options.
Loop Parse, FileList, "`n"
{
    if A_LoopField = ""  ; Ignore the blank item at the end of the list.
        continue
    Result := MsgBox("File number " A_Index " is " A_LoopField ".  Continue?",, "y/n")
    if Result = "No"
        break
}

#4: Retrieve file names sorted by modification date:

FileList := ""
Loop Files, A_MyDocuments "\Photos\*.*", "FD"  ; Include Files and Directories
    FileList .= A_LoopFileTimeModified "`t" A_LoopFileName "`n"
FileList := Sort(FileList)  ; Sort by date.
Loop Parse, FileList, "`n"
{
    if A_LoopField = "" ; Omit the last linefeed (blank item) at the end of the list.
        continue
    FileItem := StrSplit(A_LoopField, A_Tab)  ; Split into two parts at the tab char.
    Result := MsgBox("The next file (modified at " FileItem[1] ") is:`n" FileItem[2] "`n`nContinue?",, "y/n")
    if Result = "No"
        break
}

#5: Copy only the source files that are newer than their counterparts in the destination:

CopyIfNewer:
; Caller has set the variables CopySourcePattern and CopyDest for us.
Loop Files, CopySourcePattern
{
    copy_it := false
    if !FileExist(CopyDest "\" A_LoopFileName)  ; Always copy if target file doesn't yet exist.
        copy_it := true
    else
    {
        time := FileGetTime(CopyDest "\" A_LoopFileName)
        time := DateDiff(A_Now, A_LoopFileTimeModified, "Seconds")  ; Subtract the source file's time from the destination's.
        if time < 0  ; Source file is newer than destination file.
            copy_it := true
    }
    if copy_it
    {
        FileCopy A_LoopFilePath, CopyDest "\" A_LoopFileName, 1   ; Copy with overwrite=yes
        if ErrorLevel
            MsgBox 'Could not copy "' A_LoopFilePath '" to "' CopyDest '\' A_LoopFileName '".'
    }
}
Return

#6: Convert filenames passed in via command-line parameters to long names, complete path, and correct uppercase/lowercase characters as stored in the file system.

Loop A_Args.Length()  ; For each parameter (or file dropped onto a script):
{
    GivenPath := A_Args[A_Index]
    Loop Files, GivenPath, "FD"  ; Include files and directories.
        LongPath := A_LoopFilePath
    MsgBox "The case-corrected long path name of file`n" GivenPath "`nis:`n" LongPath
}