Vue Js: In the ever-changing world of Vue.js, developers frequently come to a junction in the road when determining whether to use Vue Methods or Computed Properties to handle the logic and functionality of their apps. This detailed guide will walk you through each step of constructing a prototype Vue app, illustrating the important distinctions between Vue Methods and Computed Properties and presenting real-world scenarios to assist you in making the best decisions for your projects. Prepare to improve the efficiency and functionality of your Vue.js application.
Step 1: Setting Up Your Vue js Project
Let’s start with a simple Vue.js project before digging into the world of Vue Methods and Computed Properties. To create our application, we’ll use the Vue CLI.
vue create vue-methods-vs-computed
cd vue-methods-vs-computed
Step 2: Vue Methods – The Swiss Army Knife of Vue.js
The workhorses of Vue.js apps are Vue Methods. They are ideal for dealing with event listeners, user interactions, and complicated logic. Here’s an example of how to greet a user using Vue Methods:
<template>
<div>
<button @click="sayHello">Say Hello</button>
<p>{{ greeting }}</p>
</div>
</template>
<script>
export default {
data() {
return {
greeting: ''
};
},
methods: {
sayHello() {
this.greeting = 'Hello, Vue Methods!';
}
}
};
</script>
In this example, we utilize the methods property to build a sayHello method that, when the button is clicked, updates the greeting data field.
Step 3: Computed Properties – Calculated and Cached Values
"Computed properties" are ideal for managing values depending on other data attributes because they are calculated only when needed and cached for future use. Let’s look at how they calculate a user’s entire name:
<template>
<div>
<input v-model="firstName" placeholder="First Name">
<input v-model="lastName" placeholder="Last Name">
<p>{{ fullName }}</p>
</div>
</template>
<script>
export default {
data() {
return {
firstName: '',
lastName: ''
};
},
computed: {
fullName() {
return this.firstName + ' ' + this.lastName;
}
}
};
</script>
In this case, anytime the "firstName" or "lastName" changes, the fullName calculated property immediately updates. This is helpful for derived values such as entire names.
Step 4: Comparing Vue Methods and Computed Properties
Now that we’ve looked at both Vue js Methods and Computed Properties, let’s compare them using the following criteria:
- Performance: Vue Methods have a little performance overhead because they are called every time. Computed Properties, on the other hand, are more efficient for values that are dependent on other reactive data.
Step 5: Real-World Scenarios
Scenario 1: Filtering a List
Consider the following scenario: you have a list of products and wish to filter them based on certain criteria. Vue Js Methods are a fantastic solution for this assignment because they provide user interactions as well as extensive filtering logic.
Here’s how to use Vue js Methods to filter a product list:
<template>
<div>
<input v-model="search" placeholder="Search">
<ul>
<li v-for="product in filteredProducts" :key="product.id">{{ product.name }}</li>
</ul>
</div>
</template>
<script>
export default {
data() {
return {
search: '',
products: [
{ id: 1, name: 'Product A' },
{ id: 2, name: 'Product B' },
{ id: 3, name: 'Product C' },
]
};
},
methods: {
filterProducts() {
return this.products.filter(product => product.name.includes(this.search));
}
},
computed: {
filteredProducts() {
return this.filterProducts();
}
}
};
</script>
In this example, we will utilize Vue Js Methods to develop a "filterProducts" method that will filter the product list based on the search input. When "filterProducts" is invoked, the computed property "filteredProducts" is automatically updated.
Scenario 2: Dynamic Styling
Computed Properties are your go-to solution if you need to apply dynamic styling to an element based on specified conditions. They make it simple to compute and update CSS classes in response to changing data.
Here’s how Computed Properties can be used to add dynamic styling:
<template>
<div :class="elementClasses"></div>
</template>
<script>
export default {
data() {
return {
isActive: true,
isSpecial: false
};
},
computed: {
elementClasses() {
return {
active: this.isActive,
special: this.isSpecial
};
}
}
};
</script>
The "elementClasses" calculated property in this example computes the CSS classes to apply to the div element based on the "isActive" and "isSpecial" data properties. When these data properties change, the classes will automatically update.
Conclusion:
Vue Methods and Computed Properties are vital tools in your Vue.js toolbox, each with their own set of advantages and applications. You can improve the performance and maintainability of your Vue js applications by learning when to use each. Computed Properties enable efficiency and elegance when dealing with derived values and reactivity, whereas Vue Methods are your adaptable Swiss Army knife for sophisticated logic and user interactions.
We’ve covered the fundamentals, compared the two, and studied real-world scenarios to demonstrate their application in this post. With this information, you’ll be able to make informed decisions while creating Vue js apps that excel in terms of both performance and usefulness.
If you are looking for a Client from where we can upload files or images using this API, I’ve written an article “Elevate Your Vue 3 App Image Upload with Preview and API Integration” where I’ve explained in details how to upload a file using Vue 3.
Have fun coding!