General Coding Standards for Vue js.

#webdev #javascript #vue #beginners

Here are additional good and bad practices for Vue.js:

General Coding Standards

Avoid Magic Numbers and Strings:
- Use constants for values that are used repeatedly or have special meaning.

// GoodconstMAX_ITEMS=10;functionaddItem(item){if(items.length<MAX_ITEMS){items.push(item);}}// BadfunctionaddItem(item){if(items.length<10){items.push(item);}}

Usev-for Efficiently:
- When usingv-for, always provide a uniquekey to optimize rendering.

<!-- Good --><divv-for="item in items":key="item.id">     {{ item.name }}</div><!-- Bad --><divv-for="item in items">     {{ item.name }}</div>

Avoid Inline Styles:
- Prefer using CSS classes over inline styles for better maintainability.

<!-- Good --><divclass="item">{{ item.name }}</div><stylescoped>.item{color:red;}</style><!-- Bad --><div:style="{ color: 'red' }">{{ item.name }}</div>

Component Practices

Component Reusability:
- Design components to be reusable and configurable through props.

// Good<BaseButton:label="buttonLabel":disabled="isDisabled"@click="handleClick"/>// Bad<button:disabled="isDisabled"@click="handleClick">{{buttonLabel}}</button>

Prop Validation:
- Always validate props using type and required attributes.

// Goodprops:{title:{type:String,required:true},age:{type:Number,default:0}}// Badprops:{title:String,age:Number}

Avoid Long Methods:
- Break down long methods into smaller, more manageable methods.

// Goodmethods:{fetchData(){this.fetchUserData();this.fetchPostsData();},asyncfetchUserData(){...},asyncfetchPostsData(){...}}// Badmethods:{asyncfetchData(){constuserResponse=awaitfetch('api/user');this.user=awaituserResponse.json();constpostsResponse=awaitfetch('api/posts');this.posts=awaitpostsResponse.json();}}

Avoid Computed Properties with Side Effects:
- Computed properties should be used for pure computations and not for side effects.

// Goodcomputed:{fullName(){return`${this.firstName}${this.lastName}`;}}// Badcomputed:{fetchData(){// Side effect: fetch data inside a computed propertythis.fetchUserData();returnthis.user;}}

Template Practices

Usev-show vsv-if:
- Usev-show for toggling visibility without adding/removing elements from the DOM, andv-if when conditionally rendering elements.

<!-- Good: Use v-show for toggling visibility --><divv-show="isVisible">Content</div><!-- Good: Use v-if for conditional rendering --><divv-if="isLoaded">Content</div><!-- Bad: Use v-if for simple visibility toggling --><divv-if="isVisible">Content</div>

Avoid Large Templates:
- Keep templates clean and small; break them into smaller components if they become too large.

<!-- Good: Small, focused template --><template><div><BaseHeader/><BaseContent/><BaseFooter/></div></template><!-- Bad: Large, monolithic template --><template><div><header>...</header><main>...</main><footer>...</footer></div></template>

State Management Practices

Use Vuex for State Management:
- Use Vuex for managing complex state across multiple components.

// Good// store.jsexportdefaultnewVuex.Store({state:{user:{}},mutations:{setUser(state,user){state.user=user;}},actions:{asyncfetchUser({commit}){constuser=awaitfetchUserData();commit('setUser',user);}}});

Avoid Direct State Mutation in Components:
- Use mutations to modify Vuex state rather than directly mutating state in components.

// Goodmethods:{updateUser(){this.$store.commit('setUser',newUser);}}// Badmethods:{updateUser(){this.$store.state.user=newUser;// Direct mutation}}

Error Handling and Debugging

Global Error Handling:
- Use Vue’s global error handler for catching and handling errors.

Vue.config.errorHandler=function(err,vm,info){console.error('Vue error:',err);};

Provide User Feedback:
- Provide clear feedback to users when an error occurs.

// Goodmethods:{asyncfetchData(){try{constdata=awaitfetchData();this.data=data;}catch(error){this.errorMessage='Failed to load data. Please try again.';}}}// Badmethods:{asyncfetchData(){try{this.data=awaitfetchData();}catch(error){console.error('Error fetching data:',error);}}}