Skill: AL File Handling

Validation Gates

1. After Step 1: UploadIntoStream opens file dialog, InStream contains data
2. After Step 2: Attachment saved to Document Attachment or custom table
3. Final: XMLport imports/exports successfully, Azure Blob upload returns IsSuccessful()

Note: ALWAYS CalcFields(BlobField) before CreateInStream. Web Client allows only ONE DownloadFromStream per request.

Procedure

Step 1: Upload/Download Files

// Upload
if UploadIntoStream('Select file', '', 'All Files (*.*)|*.*', FileName, InStr) then
    // Process InStr

// Download - MUST CalcFields first for Blob
CalcFields("File Content");
if "File Content".HasValue() then begin
    "File Content".CreateInStream(InStr);
    DownloadFromStream(InStr, '', '', '', FileName);
end;

Step 2: Document Attachments

Standard (Table 1173):

// Replace <SourceTable> and field names with your record
DocumentAttachment.Init();
DocumentAttachment.Validate("Table ID", Database::<SourceTable>);
DocumentAttachment.Validate("No.", <Record>."<KeyField>");
DocumentAttachment.Validate("Document Type", <Record>."<TypeField>");  // If applicable
DocumentAttachment.InsertFromStream(InStr, FileName);

Custom Blob field:

Rec."File Content".CreateOutStream(OutStr);
CopyStream(OutStr, InStr);
Rec.Modify();

Step 3: XMLport Import/Export

xmlport <ID> "<PREFIX> Import Data"
{
    Direction = Import;
    Format = VariableText;
    FieldDelimiter = '"';
    FieldSeparator = ';';
    TextEncoding = UTF8;

    schema
    {
        textelement(Root)
        {
            tableelement(TempImport; "<PREFIX> Import Buffer")
            {
                UseTemporary = true;
                AutoSave = false;
                fieldelement(ItemNo; TempImport."Item No.") { }
                fieldelement(Description; TempImport.Description) { }
                trigger OnAfterInsertRecord()
                begin
                    ProcessLine(TempImport);
                end;
            }
        }
    }
}

Key properties: Direction (Import/Export/Both), Format (Xml/VariableText/FixedText), TextEncoding (UTF8/UTF16)

Step 4: Azure Blob Storage (Optional)

var
    ABSBlobClient: Codeunit "ABS Blob Client";
    StorageServiceAuthorization: Codeunit "Storage Service Authorization";
    Authorization: Interface "Storage Service Authorization";
begin
    Authorization := StorageServiceAuthorization.CreateSAS(GetSASToken());
    ABSBlobClient.Initialize(AccountName, ContainerName, Authorization);

    // Upload
    TempBlob.CreateInStream(InStr);
    ABSOperationResponse := ABSBlobClient.PutBlobBlockBlobStream(BlobName, InStr);

    // Download
    ABSOperationResponse := ABSBlobClient.GetBlobAsStream(BlobName, InStr);
end;

Requires: Azure Storage Account + SAS Token in Isolated Storage.

Persistent Blob (Cross-Session)

// Store (returns GUID key)
BlobKey := PersistentBlob.Create();
PersistentBlob.CreateOutStream(OutStr);
OutStr.WriteText(Data);

// Retrieve
PersistentBlob.CreateInStream(BlobKey, InStr);
InStr.ReadText(Data);
PersistentBlob.Delete(BlobKey); // Clean up

⚠️ NOT for permanent storage - causes locking issues.

JSON/XML Quick Reference

// JSON
JsonObj.Add('key', 'value');
JsonObj.WriteTo(JsonText);
JsonObj.ReadFrom(JsonText);
if JsonObj.Get('key', JsonTok) then MyText := JsonTok.AsValue().AsText();

// XML
XmlDoc := XmlDocument.Create();
XmlDoc.Add(XmlElement.Create('Root'));
XmlDocument.ReadFrom(XmlText, XmlDoc);
XmlDoc.SelectSingleNode('//Child', XmlNode);

External Documentation

• InStream/OutStream
• XMLport Properties
• Azure Blob Services