DP44/enriched-partialglm/Common/DTS.Common.SharedResource.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
Common/DTS.Common.SharedResource/EnumDescriptionTypeConverterShared.cs	2026-04-16T11:30:16.984345+00:00	zai-org/GLM-5-FP8	1	accee265bcf5788d

Documentation: EnumDescriptionTypeConverterShared

1. Purpose

EnumDescriptionTypeConverterShared is a type converter that enables displaying human-readable descriptions for enumeration values instead of their raw string names. It extends System.ComponentModel.EnumConverter and is designed for UI data binding scenarios (particularly WPF). When an enum value has a System.ComponentModel.DescriptionAttribute, this converter extracts that description and optionally localizes it via the StringResources resource manager before returning it for display.

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2. Public Interface

EnumDescriptionTypeConverterShared(Type type)

Signature: Constructor

Description: Initializes a new instance of the converter for the specified enum type. Delegates to the base EnumConverter constructor.

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public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)

Signature: object ConvertTo(ITypeDescriptorContext, CultureInfo, object, Type)

Description: Converts an enum value to a display string. Behavior:

• If destinationType is not string, delegates to base.ConvertTo()
• If value is null, returns string.Empty
• If the enum field cannot be resolved via reflection, returns string.Empty
• If no DescriptionAttribute is present or the description is empty, returns value.ToString()
• If a DescriptionAttribute exists, attempts to look up the description text as a resource key via StringResources.ResourceManager.GetString()
• If the resource lookup returns null/whitespace, returns the raw description text; otherwise returns the localized string

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public static string GetEnumDescription(Enum value)

Signature: static string GetEnumDescription(Enum)

Description: A utility method that retrieves the description for an enum value. Behavior:

• Uses reflection to get the enum field's DescriptionAttribute
• If attributes exist, attempts localization via StringResources.ResourceManager.GetString()
• Returns the localized string if found; otherwise returns the raw description
• If no DescriptionAttribute is present, returns value.ToString()

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3. Invariants

• The converter only modifies output when destinationType == typeof(string); all other type conversions are passed through to the base class.
• The DescriptionAttribute.Description property is treated as a resource key first; if no matching resource is found, the raw description text is used as a fallback.
• ConvertTo always returns a non-null string (either the description, the enum name, or string.Empty).
• GetEnumDescription always returns a non-null string (either the description, the enum name, or the raw description text).

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4. Dependencies

This module depends on:

• System - Core BCL types (Type, string, object)
• System.ComponentModel - EnumConverter, DescriptionAttribute, ITypeDescriptorContext
• System.Globalization - CultureInfo
• System.Linq - Enumerable.Any() extension method
• DTS.Common.SharedResource.Strings.StringResources - Resource manager for localization lookups

Consumers:

• Not determinable from source alone. Based on the class design and referenced article URL, it is intended for WPF data binding scenarios where enum values are displayed in UI controls.

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5. Gotchas

1. Null handling inconsistency: ConvertTo has explicit null checks for value and returns string.Empty, but GetEnumDescription has no null check for its value parameter. Passing null to GetEnumDescription will throw a NullReferenceException when calling value.GetType().

2. Missing field info handling inconsistency: ConvertTo checks if fi (field info) is null and returns string.Empty, but GetEnumDescription does not perform this check. If reflection fails to find the field, GetEnumDescription will throw a NullReferenceException.

3. Resource key collision: The DescriptionAttribute.Description value is used directly as a resource key. If the description text itself is not intended as a resource key but happens to match one, unintended localization may occur.

4. Culture parameter ignored: The ConvertTo method accepts a culture parameter but does not use it; the resource manager's default culture is used instead.