Angular 20 Control Flow: The Complete Developer's Guide with Practical Examples

Angular's revolutionary Control Flow syntax has transformed how developers write conditional logic and loops in templates. With Angular 20's recent release in May 2025, these features have been further refined and stabilized, offering developers a more intuitive and powerful way to control template rendering.

What is Angular Control Flow?

Angular Control Flow introduces a new template syntax using the @ symbol that replaces traditional structural directives like *ngIf, *ngFor, and *ngSwitch. This modern approach provides better performance, improved readability, and enhanced developer experience while maintaining full backward compatibility.

Why Angular 20 Control Flow Matters

Angular 20 introduces a revolutionary approach to control flow that fundamentally changes how we build dynamic templates. Gone are the days of verbose structural directives – welcome to an era of intuitive, performant, and maintainable template logic.

• Better Performance: Optimized rendering with reduced bundle size
• Improved Readability: Cleaner, more intuitive syntax
• Enhanced Type Safety: Better TypeScript integration
• Developer Experience: Reduced cognitive load and fewer bugs
• Future-Ready: Built for Angular's reactive future

The new control flow syntax leverages Angular's signal-based reactivity system, providing unprecedented performance optimizations while maintaining the declarative nature that makes Angular templates powerful.

Also read, What's New in Angular 20: A Developer's Guide

Core Control Flow Features in Angular 20

1.@if - Mastering Conditional Rendering

The new @if syntax provides a cleaner, more intuitive way to conditionally render elements. It's optimized for performance and supports complex conditional logic.

Basic Implementation

// user-profile.component.html
@if (user.isAuthenticated) {
  <div class="user-dashboard">
    <h2>Welcome back, {{user.name}}!</h2>
    <div class="user-stats">
      <span>Last login: {{user.lastLogin | date}}</span>
    </div>
  </div>
} @else {
  <div class="login-prompt">
    <h3>Please log in to continue</h3>
    <button class="btn btn-primary" (click)="showLogin()">
      Sign In
    </button>
  </div>
}

Advanced Conditional Patterns

@if (userRole === 'admin' && hasPermissions) {
  <admin-panel [permissions]="permissions"></admin-panel>
} @else if (userRole === 'moderator') {
  <moderator-tools [userId]="user.id"></moderator-tools>
} @else if (user.isVerified) {
  <user-content [content]="userContent"></user-content>
} @else {
  <verification-required 
    [email]="user.email"
    (verified)="onUserVerified()">
  </verification-required>
}

2. @switch - Pattern Matching Made Simple

The @switch block provides a cleaner alternative to multiple @if statements when dealing with multiple conditions based on a single value.

@switch (orderStatus) {
  @case ('pending') {
    <div class="status-badge status-pending">
      <i class="fas fa-clock"></i>
      <span>Order Pending</span>
      <div class="status-description">
        Your order is being processed
      </div>
    </div>
  }
  
  @case ('processing') {
    <div class="status-badge status-processing">
      <i class="fas fa-cogs"></i>
      <span>Processing</span>
      <div class="progress-bar">
        <div class="progress-fill" [style.width.%]="processingProgress"></div>
      </div>
    </div>
  }
  
  @case ('shipped') {
    <div class="status-badge status-shipped">
      <i class="fas fa-truck"></i>
      <span>Shipped</span>
      <div class="tracking-info">
        Tracking: {{ trackingNumber }}
      </div>
    </div>
  }
  
  @case ('delivered') {
    <div class="status-badge status-delivered">
      <i class="fas fa-check-circle"></i>
      <span>Delivered</span>
      <div class="delivery-date">
        Delivered on {{ deliveryDate | date:'short' }}
      </div>
    </div>
  }
  
  @default {
    <div class="status-badge status-unknown">
      <i class="fas fa-question-circle"></i>
      <span>Status Unknown</span>
      <button (click)="refreshStatus()" class="btn btn-sm btn-outline-primary">
        Refresh
      </button>
    </div>
  }
}

3. @for - Smart Iterations That Scale

The @for directive revolutionizes list rendering with built-in optimization features, smart tracking, and enhanced performance for large datasets.

Basic List Rendering

@for (product of products; track product.id) {
  <div class="product-card" 
       [class.featured]="product.isFeatured">
    <img [src]="product.imageUrl" 
         [alt]="product.name"
         loading="lazy">
    <div class="product-info">
      <h3>{{ product.name }}</h3>
      <p class="price">{{ product.price | currency }}</p>
      <div class="product-actions">
        <button class="btn btn-primary" 
                (click)="addToCart(product)">
          Add to Cart
        </button>
      </div>
    </div>
  </div>
} @empty {
  <div class="empty-state">
    <i class="fas fa-shopping-cart fa-3x text-muted"></i>
    <h4>No products found</h4>
    <p>Try adjusting your search criteria</p>
  </div>
}

Advanced Iteration with Context Variables

@for (item of items; track item.id; let i = $index, isFirst = $first, isLast = $last) {
  <div class="list-item" 
       [class.first]="isFirst"
       [class.last]="isLast"
       [attr.data-index]="i">
    
    @if (isFirst) {
      <div class="item-header">
        <h3>Featured Item</h3>
      </div>
    }
    
    <div class="item-content">
      <span class="item-number">#{{ i + 1 }}</span>
      <h4>{{ item.title }}</h4>
      <p>{{ item.description }}</p>
    </div>
    
    @if (!isLast) {
      <hr class="item-separator">
    }
  </div>
}

Performance Benefits and Best Practices

Performance Improvements

Angular 20's Control Flow syntax offers significant performance benefits:

1. Reduced Bundle Size: Up to 30% smaller bundle sizes compared to traditional directives
2. Faster Rendering: Optimized change detection and DOM manipulation
3. Better Tree Shaking: Improved dead code elimination
4. Memory Efficiency: Reduced memory footprint for complex templates

Best Practices

1. Use Proper Tracking in @for Loops

<!-- Good: Use unique identifiers -->
@for (user of users; track user.id) {
  <user-card [user]="user"></user-card>
}

<!-- Avoid: Using index for dynamic lists -->
@for (user of users; track $index) {
  <user-card [user]="user"></user-card>
}

2. Optimize Conditional Logic

<!-- Good: Simple, readable conditions -->
@if (user?.isActive && user.hasPermission('read')) {
  <app-content></app-content>
}

<!-- Better: Extract complex logic to component -->
@if (canUserAccessContent) {
  <app-content></app-content>
}

3. Leverage @empty for Better UX

@for (notification of notifications; track notification.id) {
  <app-notification [data]="notification"></app-notification>
} @empty {
  <div class="empty-state">
    <p>No notifications yet</p>
    <button (click)="refreshNotifications()">Refresh</button>
  </div>
}

Conclusion

Angular 20's Control Flow syntax revolutionizes template development with its intuitive @ syntax, improved performance, and enhanced developer experience. By replacing traditional structural directives with more readable and efficient alternatives, Angular continues to evolve as a leading framework for modern web development.

The transition to Control Flow syntax is straightforward, with Angular's migration tools making the process seamless. Whether you're building simple components or complex applications, mastering these new features will significantly improve your development workflow and application performance.

Start incorporating Control Flow syntax in your Angular 20 projects today and experience the benefits of cleaner, more performant, and more maintainable templates.