Enum data upper case or lower case

Overview

Dart enum members can technically be named in any case, but there are clear conventions based on Dart's style guide.

Dart Style Guide — Enum Convention

Starting from Dart 2.17+, enum members should use

lowerCamelCase

UPPER_CASE

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// ✅ CORRECT — Modern Dart style (lowerCamelCase)
enum Status {
  pending,
  inProgress,
  completed,
  failed,
}

enum Direction {
  north,
  south,
  east,
  west,
}

// ❌ OLD style (avoid in modern Dart)
enum OldStyle {
  PENDING,   // Avoid — this is C/Java style
  IN_PROGRESS,
  COMPLETED,
}

Enhanced Enums (Dart 2.17+)

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enum Priority {
  low(1, 'Low Priority', Colors.green),
  medium(2, 'Medium Priority', Colors.orange),
  high(3, 'High Priority', Colors.red),
  critical(4, 'Critical!', Colors.purple);

  const Priority(this.level, this.label, this.color);

  final int level;
  final String label;
  final Color color;

  bool get isUrgent => level >= 3;

  static Priority fromLevel(int level) =>
      values.firstWhere((e) => e.level == level);
}

// Usage
final current = Priority.high;
print(current.label);    // High Priority
print(current.isUrgent); // true
print(current.color);    // Colors.red

Enum with switch (Dart 3 exhaustive)

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enum AppTheme { light, dark, system }

String getThemeLabel(AppTheme theme) {
  return switch (theme) {
    AppTheme.light => 'Light Mode',
    AppTheme.dark => 'Dark Mode',
    AppTheme.system => 'System Default',
  };
}

Common Enum Properties

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enum Fruit { apple, banana, cherry }

void main() {
  print(Fruit.apple.name);   // 'apple' (String)
  print(Fruit.apple.index);  // 0
  print(Fruit.values);       // [Fruit.apple, Fruit.banana, Fruit.cherry]

  // Parse from string
  final f = Fruit.values.byName('banana'); // Fruit.banana
}

Convention Summary

pending

inProgress

PENDING

IN_PROGRESS

Pending

InProgress

Answer: Use

textCopy

lowerCamelCase

for enum members in Dart (e.g.,

textCopy

Status.inProgress

, not

textCopy

Status.IN_PROGRESS

). This follows the official Dart style guide.