File data type

The File data type allows you to manage system files.

It helps you to develop applications that need to execute actions to the system files.

It can be used for typical operations such as copying, moving, renaming, and deleting files. You can also use it to get file attributes such as the last modification date, time, and size.

By defining variables based on this data type you are able to set and use the following properties and methods.

Properties

 

Methods

Details and samples about the methods

Copy

Copies the file specified in the source to a new location. If the target file already exists, it will be overridden.

Parameter
New filename  (Character)

Sample

&file.copy("c:\empcopiedFile.txt")

Delete

Deletes the file specified in the source.

Sample

&file.delete()

Exists

Checks whether the file specified in source exists

Returned value
Boolean

Sample

If &file.exists()
    msg("The file exists!")
Else 
    msg("The file does not exist!")
EndIf

GetName

Returns the name of the file specified in the source.

Returned value
Character

Sample

&file.Source="c:\myFile.txt"
Msg(&file.GetName()) // screen shows: myFile.txt

GetAbsoluteName

Returns the absolute name of the file specified in the source.

Returned value
Character

Sample

&file.Source="c:\empmyFile.txt"
Msg(&file.GetAbsoluteName()) // screen shows: c:\empmyFile.txt

GetPath

Returns the path of the parent directory.

Returned value
Character

Sample

&file.source = 'c:\temp\folder\emptyFile.txt'
&parentDir = &file.getPath()
Msg(&parentDir) // result: c:\temp\folder

GetURI

Returns the URI to the specified file. For local files, it is equivalent to GetAbsoluteName() but differs in external files (files returned by Storage API methods)

Returned value
Character

Sample

&file.Source="c:\empmyFile.txt"
Msg(&file.GetURI()) // screen shows: c:\empmyFile.txt

Rename

Renames the file specified in the source. It can also be used to move the file, changing its current path.

Parameter
New name of the file (Character)

Sample

&file.Rename("d:\empnewFileName.txt")

GetLastModified

Returns the date and time the file specified in the source was last modified.

Returned value
DateTime

Sample

&dateTime = &file.GetLastModified()

GetLength

Returns the size (in bytes) of the file specified in the source.

Returned value
Numeric

Sample

&size = &file.GetLength()

FromBase64String

Convert a Base64-encoded string to a human-readable string, and write it into the file. Optionally, this function returns a boolean value indicating if the operation was successful.

Parameter
Base64-string

Returned value
Boolean

Sample

&file.FromBase64String(&Base64String)

This method is not supported for user events in Native Mobile apps.

Error Codes

File data type and External Storage

File data type handles files that are in the local file system by default. But when it is returned by a method of the Storage Provider API, then it refers to a file located in the external storage. 

If it is returned by the GetFiles() method of the Directory data type and that is returned by the GetDirectories() method in the Storage Provider API, then it refers to a file located in the external storage too.

Examples when using External Storage

Suppose you have a bucket named 'mytest' and uploaded the file named 'cat.jpg' to a folder named 'petsFolder', using the Storage Provider API.

Refer to Storage Provider API for related sample code.

Security tips

When a property or method is used to assign a file's path do not use the user's inputs concatenations or sanitize the user's entries to avoid path traversal or path manipulation vulnerability risks.
 

Scope

 

See Also

File data type: Text file handling
Storage Provider API