Excel Dropdown Manager (OutSystems Extension)

Overview

Excel Dropdown Manager is an OutSystems extension that enables creation of dynamic Excel dropdown lists without the Excel 255-character limitation.

It uses EPPlus-based Excel manipulation to generate dropdown values in a hidden worksheet and binds them using Excel data validation formulas.

This approach allows scalable dropdowns with large datasets, while keeping Excel files clean and performant.

Instead of embedding values directly into validation formulas, this component:

1. Writes dropdown values into a hidden worksheet

2. Creates a dynamic Excel range reference

3. Applies data validation using Excel formulas

This completely removes the 255-character limitation.

Action: AddDropdown

Signature

AddDropdown(
    object ssWorksheet,
    string ssTargetRange,
    RLDropdownItemRecordList ssDropdownItems,
    string ssSourceRange,
    string ssPromptTitle,
    string ssPromptMessage,
    bool ssShowErrorMessage,
    string ssErrorTitle,
    string ssErrorMessage,
    bool ssAllowBlank
)

Input Parameters

1. Worksheet (Object)

Excel worksheet object where dropdown will be applied.

2. TargetRange (Text)

Cell or range where dropdown should be applied.

Examples:

• A1

• B2:B100

3. DropdownItems (Record List)

List of dropdown items with structure:

STDropdownItemStructure
- Code (Text)
- Value (Text)

Usage:

• Value → displayed in Excel dropdown

• Code → optional internal reference

4. SourceRange (Text)

Optional Excel range reference.

Examples:

• Sheet2!$A$1:$A$100

• 'Data Sheet'!$B$2:$B$50

If provided, it overrides ssDropdownItems.

5. PromptTitle (Text)

Title shown when user selects dropdown cell.

6. PromptMessage (Text)

Message shown when dropdown cell is selected.

7. ShowErrorMessage (Boolean)

Enable/disable validation error popup.

8. ErrorTitle (Text)

Title of validation error popup.

9. ErrorMessage (Text)

Message shown when invalid value is entered.

10. AllowBlank (Boolean)

Allows empty selection if true.