File
File
objects are created with the File
command. They contain references to disk files that may or may not actually exist on disk. For example, when you execute the File
command to create a new file, a valid File
object is created but nothing is actually stored on disk until you call the file.create( )
function.
Example
The following example creates a preferences file in the project folder:
var $created : Boolean
$created:=File("/PACKAGE/SpecialPrefs/"+Current user+".myPrefs").create()
Pathnames
File
objects support several pathnames, including filesystems
or posix
syntax. Supported pathnames are detailed in the Pathnames page.
File object
.copyTo( destinationFolder : 4D.Folder { ; newName : Text } { ; overwrite : Integer } ) : 4D.File copies the File object into the specified destinationFolder |
.create() : Boolean creates a file on disk according to the properties of the File object |
.createAlias( destinationFolder : 4D.Folder ; aliasName : Text { ; aliasType : Integer } ) : 4D.File creates an alias (macOS) or a shortcut (Windows) |
.creationDate : Date the creation date of the file |
.creationTime : Time the creation time of the file |
.delete() deletes the file |
.exists : Boolean true if the file exists on disk |
.extension : Text the extension of the file name (if any) |
.fullName : Text the full name of the file, including its extension (if any) |
.getAppInfo() : Object returns the contents of a .exe, .dll or .plist file information as an object |
.getContent( ) : 4D.Blobreturns a 4D.Blob object containing the entire content of a file |
.getIcon( { size : Integer } ) : Picture the icon of the file |
.getText( { charSetName : Text { ; breakMode : Integer } } ) : Text .getText( { charSetNum : Integer { ; breakMode : Integer } } ) : Text returns the contents of the file as text |
.hidden : Boolean true if the file is set as "hidden" at the system level |
.isAlias : Boolean true if the file is an alias, a shortcut, or a symbolic link |
.isFile : Boolean always true for a file |
.isFolder : Boolean always false for a file |
.isWritable : Boolean true if the file exists on disk and is writable |
.modificationDate : Date the date of the file's last modification |
.modificationTime : Time the time of the file's last modification |
.moveTo( destinationFolder : 4D.Folder { ; newName : Text } ) : 4D.File moves or renames the File object into the specified destinationFolder |
.name : Text the name of the file without extension (if any) |
.open( { mode : Text } ) : 4D.FileHandle .open( { options : Object } ) : 4D.FileHandle creates and returns a new 4D.FileHandle object on the file, in the specified mode or with the specified options |
.original : 4D.File .original : 4D.Folder the target element for an alias, a shortcut, or a symbolic link file |
.parent : 4D.Folder the parent folder object of the file |
.path : Text the POSIX path of the file |
.platformPath : Text the path of the file expressed with the current platform syntax |
.rename( newName : Text ) : 4D.File renames the file with the name you passed in newName and returns the renamed File object |
.setAppInfo( info : Object ) writes the info properties as information contents of a .exe, .dll or .plist file |
.setContent ( content : Blob ) rewrites the entire content of the file using the data stored in the content BLOB |
.setText ( text : Text {; charSetName : Text { ; breakMode : Integer } } ) .setText ( text : Text {; charSetNum : Integer { ; breakMode : Integer } } ) writes text as the new contents of the file |
.size : Real the size of the file expressed in bytes |
File
History
Release | Changes |
---|---|
19 R4 | New HTTP Client log file constant |
17 R5 | Added |
File ( path : Text { ; pathType : Integer }{ ; * } ) : 4D.File
File ( fileConstant : Integer { ; * } ) : 4D.File
Parameter | Type | Description | |
---|---|---|---|
path | Text | -> | File path |
fileConstant | Integer | -> | 4D file constant |
pathType | Integer | -> | fk posix path (default) or fk platform path |
* | -> | * to return file of host database | |
Result | 4D.File | <- | New file object |
Description
The File
command creates and returns a new object of the 4D.File
type. The command accepts two syntaxes:
File ( path { ; pathType } { ; * })
In the path parameter, pass a file path string. You can use a custom string or a filesystem (e.g., "/DATA/myfile.txt").
Only absolute pathnames are supported with the
File
command.
By default, 4D expects a path expressed with the POSIX syntax. If you work with platform pathnames (Windows or macOS), you must declare it using the pathType parameter. The following constants are available:
Constant | Value | Comment |
---|---|---|
fk platform path | 1 | Path expressed with a platform-specific syntax (mandatory in case of platform pathname) |
fk posix path | 0 | Path expressed with POSIX syntax (default) |
File ( fileConstant { ; * } )
In the fileConstant parameter, pass a 4D built-in or system file, using one of the following constants:
Constant | Value | Comment |
---|---|---|
Backup history file | 19 | Backup history file (see Configuration and trace files). Stored in the backup destination folder. |
Backup log file | 13 | Current backup journal file. Stored in the application Logs folder. |
Backup settings file | 1 | Default backup.4DSettings file (xml format), stored in the Settings folder of the project |
Backup settings file for data | 17 | backup.4DSettings file (xml format) for the data file, stored in the Settings folder of the data folder |
Build application log file | 14 | Current log file in xml format of the application builder. Stored in the Logs folder. |
Build application settings file | 20 | Default settings file of the application builder ("buildApp.4DSettings"). Stored in the Settings folder of the project. |
Compacting log file | 6 | Log file of the most recent compacting done with the Compact data file command or the Maintenance and security center. Stored in the Logs folder. |
Current backup settings file | 18 | backup.4DSettings file currently used by the application. It can be the backup settings file (default) or a custom user backup settings file defined for the data file |
Debug log file | 12 | Log file created by the SET DATABASE PARAMETER(Debug log recording) command. Stored in the Logs folder. |
Diagnostic log file | 11 | Log file created by the SET DATABASE PARAMETER(Diagnostic log recording) command. Stored in the Logs folder. |
Directory file | 16 | directory.json file, containing the description of users and groups (if any) for the project application. It can be located either in the user settings folder (default, global to the project), or in the data settings folder (specific to a data file). |
HTTP Client log file | 24 | Log file created by the HTTP SET OPTION(HTTP client log) command. Stored in the Logs folder. |
HTTP debug log file | 9 | Log file created by the WEB SET OPTION(Web debug log) command. Stored in the Logs folder. |
HTTP log file | 8 | Log file created by the WEB SET OPTION(Web log recording) command. Stored in Logs folder. |
IMAP Log file | 23 | Log file created by the SET DATABASE PARAMETER(IMAP Log) command. Stored in the Logs folder. |
Last backup file | 2 | Last backup file, named \<applicationName>[bkpNum].4BK , stored at a custom location. |
Last journal integration log file | 22 | Full pathname of the last journal integration log file (stored in the Logs folder of the restored application), if any. This file is created, in auto-repair mode, as soon as a log file integration occurred |
Repair log file | 7 | Log file of database repairs made on the database in the Maintenance and Security Center (MSC). Stored in the Logs folder. |
Request log file | 10 | Standard client/server request log file (excluding Web requests) created by the SET DATABASE PARAMETER(4D Server log recording) or SET DATABASE PARAMETER(Client log recording) commands. If executed on the server, the server log file is returned (stored in the Logs folder on the server). If executed on the client, the client log file is returned (stored in the client local Logs folder). |
SMTP log file | 15 | Log file created by the SET DATABASE PARAMETER(SMTP Log) command. Stored in the Logs folder. |
User settings file | 3 | settings.4DSettings file for all data files, stored in Preferences folder next to structure file if enabled. |
User settings file for data | 4 | settings.4DSettings file for current data file, stored in Preferences folder next to the data file. |
Verification log file | 5 | Log files created by the VERIFY CURRENT DATA FILE and VERIFY DATA FILE commands or the Maintenance and Security Center (MSC). Stored in the Logs folder. |
If the target fileConstant does not exist, a null object is returned. No errors are raised.
If the command is called from a component, pass the optional *
parameter to get the path of the host database. Otherwise, if you omit the *
parameter, a null object is always returned.
4D.File.new()
History
Release | Changes |
---|---|
18 R6 | Added |
4D.File.new ( path : Text { ; pathType : Integer } ) : 4D.File
4D.File.new ( fileConstant : Integer ) : 4D.File
Description
The 4D.File.new()
function creates and returns a new object of the 4D.File
type. It is identical to the File
command (shortcut).
It is recommended to use the
File
shortcut command instead of4D.File.new()
.
.copyTo()
History
Release | Changes |
---|---|
17 R5 | Added |
.copyTo( destinationFolder : 4D.Folder { ; newName : Text } { ; overwrite : Integer } ) : 4D.File
Parameter | Type | Description | |
---|---|---|---|
destinationFolder | 4D.Folder | -> | Destination folder |
newName | Text | -> | Name for the copy |
overwrite | Integer | -> | fk overwrite to replace existing elements |
Result | 4D.File | <- | Copied file |
Description
The .copyTo()
function copies the File
object into the specified destinationFolder .
The destinationFolder must exist on disk, otherwise an error is generated.
By default, the file is copied with the name of the original file. If you want to rename the copy, pass the new name in the newName parameter. The new name must comply with naming rules (e.g., it must not contain characters such as ":", "/", etc.), otherwise an error is returned.
If a file with the same name already exists in the destinationFolder, by default 4D generates an error. You can pass the fk overwrite
constant in the overwrite parameter to ignore and overwrite the existing file
Constant | Value | Comment |
---|---|---|
fk overwrite | 4 | Overwrite existing elements, if any |
Returned value
The copied File
object.
Example
You want to copy a picture file from the user's document folder to the application folder:
var $source; $copy : Object
$source:=Folder(fk documents folder).file("Pictures/photo.png")
$copy:=$source.copyTo(Folder("/PACKAGE");fk overwrite)
.create()
History
Release | Changes |
---|---|
17 R5 | Added |
Not available for ZIP archives
.create() : Boolean
Parameter | Type | Description | |
---|---|---|---|
Result | Boolean | <- | True if the file was created successfully, false otherwise |
Description
The .create()
function creates a file on disk according to the properties of the File
object.
If necessary, the function creates the folder hierachy as described in the platformPath or path properties. If the file already exists on disk, the function does nothing (no error is thrown) and returns false.
Returned value
- True if the file is created successfully;
- False if a file with the same name already exists or if an error occured.
Example
Creation of a preferences file in the database folder:
var $created : Boolean
$created:=File("/PACKAGE/SpecialPrefs/"+Current user+".myPrefs").create()
.createAlias()
History
Release | Changes |
---|---|
17 R5 | Added |
.createAlias( destinationFolder : 4D.Folder ; aliasName : Text { ; aliasType : Integer } ) : 4D.File
Parameter | Type | Description | |
---|---|---|---|
destinationFolder | 4D.Folder | -> | Destination folder for the alias or shortcut |
aliasName | Text | -> | Name of the alias or shortcut |
aliasType | Integer | -> | Type of the alias link |
Result | 4D.File | <- | Alias or shortcut file reference |
Description
The .createAlias()
function creates an alias (macOS) or a shortcut (Windows) to the file with the specified aliasName name in the folder designated by the destinationFolder object.
Pass the name of the alias or shortcut to create in the aliasName parameter.
By default on macOS, the function creates a standard alias. You can also create a symbolic link by using the aliasType parameter. The following constants are available:
Constant | Value | Comment |
---|---|---|
fk alias link | 0 | Alias link (default) |
fk symbolic link | 1 | Symbolic link (macOS only) |
On Windows, a shortcut (.lnk file) is always created (the aliasType parameter is ignored).
Returned object
A 4D.File
object with the isAlias
property set to true.
Example
You want to create an alias to a file in your database folder:
$myFile:=Folder(fk documents folder).file("Archives/ReadMe.txt")
$aliasFile:=$myFile.createAlias(File("/PACKAGE");"ReadMe")
.creationDate
History
Release | Changes |
---|---|
17 R5 | Added |
.creationDate : Date
Description
The .creationDate
property returns the creation date of the file.
This property is read-only.
.creationTime
History
Release | Changes |
---|---|
17 R5 | Added |
.creationTime : Time
Description
The .creationTime
property returns the creation time of the file (expressed as a number of seconds beginning at 00:00).
This property is read-only.
.delete()
History
Release | Changes |
---|---|
17 R5 | Added |
.delete()
Parameter | Type | Description | |
---|---|---|---|
Does not require any parameters |
Description
The .delete()
function deletes the file.
If the file does not exist on disk, the function does nothing (no error is generated).
If the file is currently open, the result depends on the OS:
- on Windows, an error is generated,
- on macOS, no error is generated and the file is deleted.
.delete()
can delete any file on a disk. This includes documents created with other applications, as well as the applications themselves. .delete()
should be used with extreme caution. Deleting a file is a permanent operation and cannot be undone.
Example
You want to delete a specific file in the database folder:
$tempo:=File("/PACKAGE/SpecialPrefs/"+Current user+".prefs")
If($tempo.exists)
$tempo.delete()
ALERT("User preference file deleted.")
End if
.exists
History
Release | Changes |
---|---|
17 R5 | Added |
.exists : Boolean
Description
The .exists
property returns true if the file exists on disk, and false otherwise.
This property is read-only.
.extension
History
Release | Changes |
---|---|
17 R5 | Added |
.extension : Text
Description
The .extension
property returns the extension of the file name (if any). An extension always starts with ".". The property returns an empty string if the file name does not have an extension.
This property is read-only.
.fullName
History
Release | Changes |
---|---|
17 R5 | Added |
.fullName : Text
Description
The .fullName
property returns the full name of the file, including its extension (if any).
This property is read-only.
.getAppInfo()
History
Release | Changes |
---|---|
19 | Added |
.getAppInfo() : Object
Parameter | Type | Description | |
---|---|---|---|
Result | Object | <- | Contents of .exe/.dll version resource or .plist file |
Description
The .getAppInfo()
function returns the contents of a .exe, .dll or .plist file information as an object.
The function must be used with an existing .exe, .dll or .plist file. If the file does not exist on disk or is not a valid .exe, .dll or .plist file, the function returns an empty object (no error is generated).
The function only supports .plist files in xml format (text-based). An error is returned if it is used with a .plist file in binary format.
Returned object with a .exe or .dll file
Reading a .exe or .dll is only possible on Windows.
All property values are Text.
Property | Type |
---|---|
InternalName | Text |
ProductName | Text |
CompanyName | Text |
LegalCopyright | Text |
ProductVersion | Text |
FileDescription | Text |
FileVersion | Text |
OriginalFilename | Text |
Returned object with a .plist file
The xml file contents is parsed and keys are returned as properties of the object, preserving their types (text, boolean, number). .plist dict
is returned as a JSON object and .plist array
is returned as a JSON array.
Example
// display copyright info of application .exe file (windows)
var $exeFile : 4D.File
var $info : Object
$exeFile:=File(Application file; fk platform path)
$info:=$exeFile.getAppInfo()
ALERT($info.LegalCopyright)
// display copyright info of an info.plist (any platform)
var $infoPlistFile : 4D.File
var $info : Object
$infoPlistFile:=File("/RESOURCES/info.plist")
$info:=$infoPlistFile.getAppInfo()
ALERT($info.Copyright)
See also
.getContent()
History
Release | Changes |
---|---|
19 R2 | Returns 4D.Blob |
17 R5 | Added |
.getContent( ) : 4D.Blob
Parameter | Type | Description | |
---|---|---|---|
Result | 4D.Blob | <- | File content |
Description
The .getContent()
function returns a 4D.Blob
object containing the entire content of a file. For information on BLOBs, please refer to the BLOB section.
Returned value
A 4D.Blob
object.
Example
To save a document's contents in a BLOB
field:
var $vPath : Text
$vPath:=Select document("";"*";"Select a document";0)
If(OK=1) //If a document has been chosen
[aTable]aBlobField:=File($vPath;fk platform path).getContent()
End if
.getIcon()
History
Release | Changes |
---|---|
17 R5 | Added |
.getIcon( { size : Integer } ) : Picture
Parameter | Type | Description | |
---|---|---|---|
size | Integer | -> | Side length for the returned picture (pixels) |
Result | Picture | <- | Icon |
Description
The .getIcon()
function returns the icon of the file.
The optional size parameter specifies the dimensions in pixels of the returned icon. This value actually represents the length of the side of the square containing the icon. Icons are usually defined in 32x32 pixels (“large icons”) or 16x16 pixels (“small icons”). If you pass 0 or omit this parameter, the "large icon" version is returned.
If the file does not exist on disk, a default blank icon is returned.
Returned value
File icon picture.
.getText()
History
Release | Changes |
---|---|
17 R5 | Added |
.getText( { charSetName : Text { ; breakMode : Integer } } ) : Text
.getText( { charSetNum : Integer { ; breakMode : Integer } } ) : Text
Parameter | Type | Description | |
---|---|---|---|
charSetName | Text | -> | Name of character set |
charSetNum | Integer | -> | Number of character set |
breakMode | Integer | -> | Processing mode for line breaks |
Result | Text | <- | Text from the document |
Description
The .getText()
function returns the contents of the file as text .
Optionally, you can designate the character set to be used for reading the contents. You can pass either:
- in charSetName, a string containing the standard set name (for example "ISO-8859-1" or "UTF-8"),
- or in charSetNum, the MIBEnum ID (number) of the standard set name.
For the list of character sets supported by 4D, refer to the description of the
CONVERT FROM TEXT
command.
If the document contains a Byte Order Mark (BOM), 4D uses the character set that it has set instead of the one specified in charSetName or charSetNum (this parameter is then ignored). If the document does not contain a BOM and if charSetName or charSetNum is omitted, by default 4D uses the "UTF-8" character set.
In breakMode, you can pass a number indicating the processing to apply to end-of-line characters in the document. The following constants of the "System Documents" theme are available:
Constant | Value | Comment |
---|---|---|
Document unchanged | 0 | No processing |
Document with native format | 1 | (Default) Line breaks are converted to the native format of the operating system: CR (carriage return) under OS X, CRLF (carriage return + line feed) under Windows |
Document with CRLF | 2 | Line breaks are converted to Windows format: CRLF (carriage return + line feed) |
Document with CR | 3 | Line breaks are converted to OS X format: CR (carriage return) |
Document with LF | 4 | Line breaks are converted to Unix format: LF (line feed) |
By default, when you omit the breakMode parameter, line breaks are processed in native mode (1).
Returned value
Text of the file.
Example
Given the following text document (fields are separated by tabs):
id name price vat
3 thé 1.06€ 19.6
2 café 1.05€ 19.6
When you execute this code:
$myFile:=Folder(fk documents folder).file("Billing.txt") //UTF-8 by default
$txt:=$myFile.getText()
... you get the following for $txt
:
"id\tname\tprice\tvat\r\n3\tthé\t1.06€\t19.6\r\n2\tcafé\t1.05€\t19.6"
with \t
(tab) as separator and \r\n
(CRLF) as line delimiter.
Here is another example with the same file, but a different line delimiter:
$txt:=$myFile.getText("UTF-8"; Document with LF)
In this case, the contents of $txt
are as follows:
"id\tname\tprice\tvat\n3\tthé\t1.06€\t19.6\n2\tcafé\t1.05€\t19.6"
This time \n
(LF) is used as line delimiter.
.hidden
History
Release | Changes |
---|---|
17 R5 | Added |
.hidden : Boolean
Description
The .hidden
property returns true if the file is set as "hidden" at the system level, and false otherwise.
This property is read/write.
.isAlias
History
Release | Changes |
---|---|
17 R5 | Added |
.isAlias : Boolean