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Hany Taha
Hany Taha

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Mastering Vue 3: A Comprehensive Guide to Building Modern Web Applications <Part 6 />

Content:

  1. Mastering Vue 3 - Part 1 [Introduction and key features]

2. Mastering Vue 3 - Part 2 [Benefits of using Vue 3 for web development]

3. Mastering Vue 3 - Part 3 [Template syntax in Vue 3]

4. Mastering Vue 3 - Part 4 [Reactivity Fundamentals]

5. Mastering Vue 3 - Part 5 [Class and Style Bindings]

6. Mastering Vue 3 - Part 6 [Lifecycle Hooks]

7. Mastering Vue 3 - Part 7 [Understanding components in Vue 3]

8. Mastering Vue 3 - Part 8 [Installing Vue project and file structure]

9. Mastering Vue 3 - Part 9 [Vue Router in Vue 3]

10. Mastering Vue 3 - Part 10 [Animation in Vue 3]

11. Mastering Vue 3 - Part 11 [State Management with Pinia]

12. Mastering Vue 3 - Part 12 [Teleport in Vue 3]

13. Mastering Vue 3 - Part 13 [Working with API Calls ]

14. Mastering Vue 3 - Part 14 [Forms and Form Validation ]


Lifecycle Hooks

In Vue 3, the concept of lifecycle hooks has been replaced with the Composition API, which provides a more flexible and intuitive way to manage component logic. Instead of using specific lifecycle hooks, you can use composition functions to encapsulate and reuse code.

The Composition API introduces a set of functions that can be used inside the setup function of a component to define reactive data, computed properties, methods, and more. These functions are not tied to specific lifecycle stages, but rather allow you to organize your component logic in a more granular and composable way.

Here are some important composition functions available in Vue 3:

1. **setup function:**
The setup function is the entry point of a component and is called before the component is created. It is where you define reactive data, computed properties, methods, and component setup logic.

<script>
import { reactive, computed } from 'vue';

export default {
  setup() {
    const state = reactive({
      message: 'Hello, Vue 3!',
      count: 0
    });

    const doubleCount = computed(() => state.count * 2);

    function increment() {
      state.count++;
    }

    return {
      state,
      doubleCount,
      increment
    };
  }
};
</script>
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In this example, the setup function defines reactive data (state), a computed property (doubleCount), and a method (increment).

2. **onMounted:**
The onMounted function is used to perform actions when the component is mounted to the DOM. It is similar to the mounted lifecycle hook in Vue 2.

<script>
import { onMounted } from 'vue';

export default {
  setup() {
    onMounted(() => {
      console.log('Component mounted');
    });
  }
};
</script>
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In this example, the onMounted function is used to log a message when the component is mounted.

3. **onUpdated:**
The onUpdated function is used to perform actions when the component is updated and re-rendered. It is similar to the updated lifecycle hook in Vue 2.

<script>
import { onUpdated } from 'vue';

export default {
  setup() {
    onUpdated(() => {
      console.log('Component updated');
    });
  }
};
</script>
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In this example, the onUpdated function is used to log a message when the component is updated.

4. **onUnmounted:**
The onUnmounted function is used to perform cleanup actions when the component is unmounted from the DOM. It is similar to the beforeUnmount lifecycle hook in Vue 2.

<script>
import { onUnmounted } from 'vue';

export default {
  setup() {
    onUnmounted(() => {
      console.log('Component unmounted');
    });
  }
};
</script>
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In this example, the onUnmounted function is used to log a message when the component is unmounted.

These are just a few examples of the composition functions available in the Composition API. By using these functions, you can organize your component logic in a more modular and reusable way, without being tied to specific lifecycle hooks.
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