DP44/enriched-qwen3-coder-next/Common/DTS.Common/Interface/DownloadEvent.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
Common/DTS.Common/Interface/DownloadEvent/IDownloadEvent.cs	2026-04-16T03:00:13.552600+00:00	Qwen/Qwen3-Coder-Next-FP8	1	e451d0fb97802f82

DownloadEvent

Documentation Page: IDownloadEvent Interface

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1. Purpose

The IDownloadEvent interface defines the contract for a download event—a configurable unit representing a single downloadable test scenario or asset within the DTS (Device Test System) framework. It enables UI binding and dynamic state management (e.g., enabling/disabling, read-only status) of individual download events, while exposing metadata such as the associated test item, file path, and duration. As part of the DTS.Common.Interface.DownloadEvent namespace, it serves as the foundational abstraction for modeling downloadable content in test workflows, likely consumed by UI layers or orchestration logic for managing multi-event test sequences.

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2. Public Interface

interface IDownloadEvent : INotifyPropertyChanged

Represents a single download event with configurable properties and change notification support.

Member	Type	Description
int EventNumber { get; set; }	Property	Numeric identifier for the event (e.g., sequence index).
string EventNumberDisplay { get; set; }	Property	Human-readable string representation of EventNumber (e.g., "1", "A", "Main"), likely used for UI labeling.
bool IsEnabled { get; set; }	Property	Controls whether the event is active and should be processed/downloaded.
bool IsReadonly { get; set; }	Property	Indicates if the event’s properties (e.g., EventNumber, DTSFile) are immutable in the UI.
bool IsDefault { get; }	Property	Read-only flag indicating whether this event is the default/fallback option.
TimeSpan EventLength { get; set; }	Property	Total duration of the downloadable content (e.g., video/audio length).
bool ShouldDisplayLength { get; set; }	Property	Controls visibility of EventLength in the UI (e.g., hide for zero-length events).
string TestItem { get; set; }	Property	Descriptive name or label for the test item associated with this event (e.g., "BootSequence").
string DTSFile { get; set; }	Property	Absolute or relative path to the downloadable file (e.g., @"C:\Tests\BootSequence.dts").

Note

: All properties except IsDefault are read-write. The interface inherits INotifyPropertyChanged, enabling data binding to react to property changes.

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3. Invariants

• IsDefault is read-only: Its value cannot be modified via the interface (no setter), implying it is determined internally (e.g., by a factory or configuration loader).
• EventLength may be zero: While EventLength is a TimeSpan, its value is not constrained—zero or negative values are not explicitly forbidden (validation, if any, occurs externally).
• ShouldDisplayLength is independent of EventLength: A non-zero EventLength may still be hidden in the UI if ShouldDisplayLength is false.
• No semantic validation: The interface does not enforce constraints such as:
  • Uniqueness of EventNumber or DTSFile.
  • Validity of DTSFile (e.g., file existence, correct extension).
  • Non-empty TestItem or DTSFile.

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4. Dependencies

• Depends on:
  • System (core types like TimeSpan, String).
  • System.ComponentModel (for INotifyPropertyChanged).
• Implied consumers:
  • UI frameworks (e.g., WPF, WinForms) leveraging INotifyPropertyChanged for data binding.
  • Test orchestration logic that iterates over IDownloadEvent instances to trigger downloads.
  • Serialization/deserialization layers (e.g., JSON/XML converters) that map IDownloadEvent implementations to/from persisted configurations.
• No direct dependencies on other DTS modules are visible in this file alone; usage context would require examining implementations (e.g., concrete classes implementing IDownloadEvent).

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5. Gotchas

• IsDefault is read-only but may be misinterpreted: Developers might assume IsDefault can be set externally (e.g., via UI), but it is likely computed (e.g., based on EventNumber == 0 or configuration metadata).
• EventNumberDisplay is decoupled from EventNumber: Changing EventNumber does not automatically update EventNumberDisplay—consumers must handle synchronization (e.g., via PropertyChanged events).
• No validation on DTSFile: The interface accepts any string, including invalid paths or non-.dts files. Validation must occur in consuming code.
• ShouldDisplayLength is a UI concern only: Its value has no impact on download logic—it is purely for presentation.
• INotifyPropertyChanged behavior is undefined here: While the interface declares the event, it does not specify which property changes trigger notifications (e.g., all setters? only specific ones?). Implementations must document this.
• No default values specified: Default values for properties (e.g., EventLength = TimeSpan.Zero, IsEnabled = true) are not guaranteed by the interface and must be enforced by implementations.

None identified from source alone.