Public API Documentation

This document describes the public API methods available for file and directory operations along with sample AL usage.

File Operations

Open and Create

Open(Name: Text; DriveAccessFileMode: Enum "Drive Access File Mode"): Boolean
Opens an existing file or creates a new one based on the specified mode.
Parameters:

Name: The file name to open or create.
DriveAccessFileMode: The file open mode (e.g., Open, Create).
Returns: Boolean indicating success or failure.

Open(Name: Text): Boolean
Opens an existing file.
Parameters:

Name: The file name to open.
Returns: Boolean indicating success or failure.

Create(Name: Text): Boolean
Creates a new file.
Parameters:

Name: The file name to create.
Returns: Boolean indicating success or failure.

Parameters:

Name: File name.
DriveAccessFileMode: The mode (e.g., Open, Create).

Sample Code:

var
    DriveFile: Codeunit "Drive Access File";
begin
    // Open an existing file
    if DriveFile.Open('MyFile.txt') then;

    // Create a new file
    if DriveFile.Create('NewFile.txt') then;
end;

Read Operations

Read(var OutStream: OutStream; NumberOfBytes: Integer; var IsEndOfFile: Boolean): Integer
Reads data from an open file into an output stream.
Parameters:

OutStream: The output stream for received data.
NumberOfBytes: Number of bytes to read (0 for all).
IsEndOfFile: Indicates if the end of file was reached.
Returns: Number of bytes actually read.

Read(var OutStream: OutStream; NumberOfBytes: Integer): Integer
Reads into an output stream without returning end-of-file info.
Parameters:

OutStream: Destination for data.
NumberOfBytes: Bytes to read (0=all).
Returns: Bytes read.

Read(var OutStream: OutStream): Integer
Reads all available data into an output stream.
Parameters:

OutStream: Destination stream.
Returns: Bytes read.

Read(var Data: Text; NumberOfBytes: Integer; var IsEndOfFile: Boolean): Integer
Reads text data.
Parameters:

Data: Variable to store the text read.
NumberOfBytes: Number of bytes to read (0 for all).
IsEndOfFile: Indicates if the end of file was reached.
Returns: Number of bytes actually read.

Read(var Data: Text; NumberOfBytes: Integer): Integer
Reads text data without returning end-of-file info.
Parameters:

Data: Destination string.
NumberOfBytes: Bytes to read (0=all).
Returns: Bytes read.

Read(var Data: Text): Integer
Reads all available text data.
Parameters:

Data: Destination text.
Returns: Bytes read.

Sample Code:

var
    DriveFile: Codeunit "Drive Access File";
    OutStream: OutStream;
    BytesRead: Integer;
    EndOfFile: Boolean;
begin
    // Assuming the file is already open
    BytesRead := DriveFile.Read(OutStream, 1024, EndOfFile);
end;

You can also read text:

var
    DriveFile: Codeunit "Drive Access File";
    Data: Text;
    BytesRead: Integer;
begin
    BytesRead := DriveFile.Read(Data, 1024);
end;

Write Operations

Write(var InStream: InStream; NumberOfBytes: Integer): Boolean
Writes binary data from an input stream.
Parameters:

InStream: The input stream containing data.
NumberOfBytes: The number of bytes to write.
Returns: Boolean indicating success or failure.

Write(Text: Text): Boolean
Writes text data.
Parameters:

Text: The text to write.
Returns: Boolean indicating success or failure.

Sample Code:

var
    DriveFile: Codeunit "Drive Access File";
    InStream: InStream;
begin
    // To write text
    if DriveFile.Write('Hello World') then;

    // To write from a stream (assume InStream is set up)
    if DriveFile.Write(InStream, 512) then;
end;

Seek and Close

Seek(Position: Integer): Boolean
Moves the file pointer to a specified position.
Parameters:

Position: The zero-based position in the file.
Returns: Boolean indicating success or failure.

Close(): Boolean
Closes the open file.
Returns: Boolean indicating success or failure.

Sample Code:

var
    DriveFile: Codeunit "Drive Access File";
begin
    if DriveFile.Seek(0) then;
    if DriveFile.Close() then;
end;

Directory Operations

ReadDirectory, CreateDirectory, and DeleteDirectory

ReadDirectory(Path: Text; var Rec: Record "Drive Access File"): Boolean
Reads directory contents into a record.
Parameters:

Path: The directory path.
Rec: Temporary record to store directory entries.
Returns: Boolean indicating success or failure.

Sample Code:

var
    DriveFile: Codeunit "Drive Access File";
    DirRec: Record "Drive Access File";
begin
    // Read directory contents
    if DriveFile.ReadDirectory('C:\Temp', DirRec) then;

    // Create a new directory
    if DriveFile.CreateDirectory('C:\Temp\NewFolder') then;

    // Delete the directory recursively
    if DriveFile.DeleteDirectory('C:\Temp\NewFolder', true) then;
end;

CreateDirectory(Path: Text): Boolean
Creates a new directory.
Parameters:

Path: The directory path to create.
Returns: Boolean indicating success or failure.

DeleteDirectory(Path: Text; Recursive: Boolean): Boolean
Deletes a directory (optionally recursively).
Parameters:

Path: The directory path to delete.
Recursive: Whether to remove contents recursively.
Returns: Boolean indicating success or failure.

File Management

Delete, Rename, Exists, Upload and Download

DeleteFile(Name: Text): Boolean
Deletes the specified file.
Parameters:

Name: The file name to delete.
Returns: Boolean indicating success or failure.

Sample Code:

var
    DriveFile: Codeunit "Drive Access File";
    TempBlob: Codeunit "Temp Blob";
begin
    // Delete a file
    if DriveFile.DeleteFile('OldFile.txt') then;

    // Rename a file
    if DriveFile.Rename('FileA.txt', 'FileB.txt') then;

    // Check existence
    if DriveFile.Exists('FileB.txt') then;

    // Upload file
    if DriveFile.UploadFile('C:\UploadFolder', 'FileB.txt', TempBlob) then;

    // Download file
    if DriveFile.DownloadFile('C:\DownloadFolder\FileB.txt', TempBlob) then;
end;

Rename(FromName: Text; ToName: Text): Boolean
Renames a file.
Parameters:

FromName: The existing file name.
ToName: The new file name.
Returns: Boolean indicating success or failure.

Exists(Name: Text): Boolean
Checks if a file exists.
Parameters:

Name: The file to check.
Returns: Boolean indicating the presence of the file.

UploadFile(Path: Text; Filename: Text; TempBlob: Codeunit "Temp Blob"): Boolean
Uploads a file to the given path.
Parameters:

Path: The(upload) folder path.
Filename: Name of the file to upload.
TempBlob: Codeunit for file data.
Returns: Boolean indicating success or failure.

DownloadFile(Path: Text; var TempBlob: Codeunit "Temp Blob"): Boolean
Downloads a file from the given path.
Parameters:

Path: The file path to download.
TempBlob: Codeunit for receiving file data.
Returns: Boolean indicating success or failure.

Copy and Move

Copy(SourcePath: Text; DestinationPath: Text): Boolean
Copies a file from one location to another.
Parameters:

SourcePath: The path of the source file.
DestinationPath: The target path.
Returns: Boolean indicating success or failure.

Move(SourcePath: Text; DestinationPath: Text): Boolean
Moves a file from one location to another.
Parameters:

SourcePath: The path of the file to move.
DestinationPath: The target path.
Returns: Boolean indicating success or failure.

Sample Code:

var
    DriveFile: Codeunit "Drive Access File";
begin
    // Example use for copy and move when implemented:
    // if DriveFile.Copy('C:\Source\File.txt', 'C:\Destination\File.txt') then;
    // if DriveFile.Move('C:\Source\File.txt', 'C:\Destination\File.txt') then;
end;

Configuration and Setup

SetDriveAccess

SetDriveAccess(DriveAccessCode: Code[20])
Sets up the current drive access using a drive access code.
Parameters:

DriveAccessCode: The code referencing the drive access record.
Returns: None (procedure updates current config).

SetDriveAccess(DriveAccess: Record "Drive Access")
Sets up the drive access using a full record.
Parameters:

DriveAccess: The record containing drive access info.
Returns: None (procedure updates current config).

Sample Code:

var
    DriveFile: Codeunit "Drive Access File";
begin
    // Using a drive access code
    DriveFile.SetDriveAccess('ACCESS_CODE');

    // Or using a drive access record (assume DriveAccessRec is defined and initialized)
    // DriveFile.SetDriveAccess(DriveAccessRec);
end;

Drive Access for Business Central - Extension API Documentation

Public API Documentation

File Operations

Open and Create

Read Operations

Write Operations

Seek and Close

Directory Operations

ReadDirectory, CreateDirectory, and DeleteDirectory

File Management

Delete, Rename, Exists, Upload and Download

Copy and Move

Configuration and Setup

SetDriveAccess