Angular vs Vue 2 Comparison

Reactivity

Declare state

Angular

import { Component, NgModule } from "@angular/core";

@Component({
  selector: "app-name",
  template: `<h1>Hello {{ name }}</h1>`,
})
export class NameComponent {
  name = "John";
}

@NgModule({
  declarations: [NameComponent],
  exports: [NameComponent],
})
export class NameModule {}

Vue 2

<template>
  <h1>Hello {{ name }}</h1>
</template>

<script>
export default {
  data() {
    return {
      name: "John",
    };
  },
};
</script>

Update state

Angular

import { Component, NgModule } from "@angular/core";

@Component({
  selector: "app-name",
  template: `<h1>Hello {{ name }}</h1>`,
})
export class NameComponent {
  name = "John";

  constructor() {
    this.name = "Jane";
  }
}

@NgModule({
  declarations: [NameComponent],
  exports: [NameComponent],
})
export class NameModule {}

Vue 2

<template>
  <h1>Hello {{ name }}</h1>
</template>

<script>
export default {
  data() {
    return {
      name: "John",
    };
  },
  created() {
    this.name = "Jane";
  },
};
</script>

Computed state

Angular

import { Component, NgModule } from "@angular/core";

@Component({
  selector: "app-doublecount",
  template: `<div>{{ doubleCount }}</div>`,
})
export class DoublecountComponent {
  count = 10;

  get doubleCount() {
    return this.count * 2;
  }
}

@NgModule({
  declarations: [DoublecountComponent],
  exports: [DoublecountComponent],
})
export class DoublecountModule {}

Vue 2

<template>
  <div>{{ doubleCount }}</div>
</template>

<script>
export default {
  data() {
    return {
      count: 10,
    };
  },
  computed: {
    doubleCount() {
      return this.count * 2;
    },
  },
};
</script>

Templating

Minimal template

Angular

import { Component, NgModule } from "@angular/core";

@Component({
  selector: "app-helloworld",
  template: `<h1>Hello world</h1>`,
})
export class HelloworldComponent {}

@NgModule({
  declarations: [HelloworldComponent],
  exports: [HelloworldComponent],
})
export class HelloworldModule {}

Vue 2

<template>
  <h1>Hello world</h1>
</template>

Styling

Angular

import { Component, NgModule } from "@angular/core";

@Component({
  selector: "app-cssstyle",
  template: `
    <h1 class="title">I am red</h1>
    <button style="font-size: 10rem">I am a button</button>
  `,
  styles: [
    `
      .title {
        color: red;
      }
    `,
  ],
})
export class CssStyleComponent {}

@NgModule({
  declarations: [CssStyleComponent],
  exports: [CssStyleComponent],
})
export class CssStyleModule {}

Vue 2

<template>
  <div>
    <h1 class="title">I am red</h1>
    <button style="font-size: 10rem">I am a button</button>
  </div>
</template>

<style scoped>
.title {
  color: red;
}
</style>

Loop

Angular

import { Component, NgModule } from "@angular/core";
import { CommonModule } from "@angular/common";

@Component({
  selector: "app-colors",
  template: `
    <ul>
      <li *ngFor="let color of colors">{{ color }}</li>
    </ul>
  `,
})
export class ColorsComponent {
  colors = ["red", "green", "blue"];
}

@NgModule({
  declarations: [ColorsComponent],
  imports: [CommonModule],
  exports: [ColorsComponent],
})
export class ColorsModule {}

Vue 2

<template>
  <ul>
    <li v-for="color in colors" :key="color">
      {{ color }}
    </li>
  </ul>
</template>

<script>
export default {
  data() {
    return {
      colors: ["red", "green", "blue"],
    };
  },
};
</script>

Event click

Angular

import { Component, NgModule } from "@angular/core";

@Component({
  selector: "app-counter",
  template: `
    <p>Counter: {{ count }}</p>
    <button (click)="incrementCount()">+1</button>
  `,
})
export class CounterComponent {
  count = 0;

  incrementCount() {
    this.count++;
  }
}

@NgModule({
  declarations: [CounterComponent],
  exports: [CounterComponent],
})
export class CounterModule {}

Vue 2

<template>
  <div>
    <p>Counter: {{ count }}</p>
    <button @click="incrementCount">+1</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      count: 0,
    };
  },
  methods: {
    incrementCount() {
      this.count++;
    },
  },
};
</script>

Dom ref

Angular

import {
  Component,
  ViewChild,
  ElementRef,
  OnInit,
  NgModule,
} from "@angular/core";

@Component({
  selector: "app-inputfocused",
  template: `<input type="text" #inputRef />`,
})
export class InputfocusedComponent implements OnInit {
  @ViewChild("inputRef", { static: true })
  inputRef!: ElementRef<HTMLInputElement>;

  ngOnInit() {
    this.inputRef.nativeElement.focus();
  }
}

@NgModule({
  declarations: [InputfocusedComponent],
  exports: [InputfocusedComponent],
})
export class InputfocusedModule {}

Vue 2

<template>
  <input ref="inputElement" />
</template>

<script>
export default {
  mounted() {
    this.$refs.inputElement.focus();
  },
};
</script>

Conditional

Angular

import { Component, NgModule } from "@angular/core";
import { CommonModule } from "@angular/common";

const TRAFFIC_LIGHTS = ["red", "orange", "green"];

@Component({
  selector: "app-trafficlight",
  template: `
    <button (click)="nextLight()">Next light</button>
    <p>Light is: {{ light }}</p>
    <p>
      You must
      <ng-container [ngSwitch]="light">
        <span *ngSwitchCase="'red'">STOP</span>
        <span *ngSwitchCase="'orange'">SLOW DOWN</span>
        <span *ngSwitchCase="'green'">GO</span>
      </ng-container>
    </p>
  `,
})
export class TrafficlightComponent {
  lightIndex = 0;

  get light() {
    return TRAFFIC_LIGHTS[this.lightIndex];
  }

  nextLight() {
    this.lightIndex = (this.lightIndex + 1) % TRAFFIC_LIGHTS.length;
  }
}

@NgModule({
  declarations: [TrafficlightComponent],
  imports: [CommonModule],
  exports: [TrafficlightComponent],
})
export class TrafficlightModule {}

Vue 2

<template>
  <div>
    <button @click="nextLight">Next light</button>
    <p>Light is: {{ light }}</p>
    <p>
      You must
      <span v-if="light === 'red'">STOP</span>
      <span v-else-if="light === 'orange'">SLOW DOWN</span>
      <span v-else-if="light === 'green'">GO</span>
    </p>
  </div>
</template>

<script>
export default {
  data() {
    return {
      TRAFFIC_LIGHTS: ["red", "orange", "green"],
      lightIndex: 0,
    };
  },
  computed: {
    light() {
      return this.TRAFFIC_LIGHTS[this.lightIndex];
    },
  },
  methods: {
    nextLight() {
      this.lightIndex = (this.lightIndex + 1) % this.TRAFFIC_LIGHTS.length;
    },
  },
};
</script>

Lifecycle

On mount

Angular

import { Component, NgModule, OnInit } from "@angular/core";

@Component({
  selector: "app-pagetitle",
  template: `<p>Page title: {{ pageTitle }}</p>`,
})
export class PagetitleComponent implements OnInit {
  pageTitle = "";

  ngOnInit() {
    this.pageTitle = document.title;
  }
}

@NgModule({
  declarations: [PagetitleComponent],
  exports: [PagetitleComponent],
})
export class PagetitleModule {}

Vue 2

<template>
  <p>Page title: {{ pageTitle }}</p>
</template>

<script>
export default {
  data() {
    return {
      pageTitle: "",
    };
  },
  mounted() {
    this.pageTitle = document.title;
  },
};
</script>

On unmount

Angular

import { Component, NgModule, OnDestroy } from "@angular/core";

@Component({
  selector: "app-time",
  template: `<p>Current time: {{ time }}</p>`,
})
export class TimeComponent implements OnDestroy {
  time = new Date().toLocaleTimeString();

  timer = setInterval(() => {
    this.time = new Date().toLocaleTimeString();
  }, 1000);

  ngOnDestroy() {
    clearInterval(this.timer);
  }
}

@NgModule({
  declarations: [TimeComponent],
  exports: [TimeComponent],
})
export class TimeModule {}

Vue 2

<template>
  <p>Current time: {{ time }}</p>
</template>

<script>
export default {
  data() {
    return {
      time: new Date().toLocaleTimeString(),
      timer: null,
    };
  },
  mounted() {
    this.timer = setInterval(() => {
      this.time = new Date().toLocaleTimeString();
    }, 1000);
  },
  beforeDestroy() {
    clearInterval(this.timer);
  },
};
</script>

Component composition

Props

Angular

import { Component, NgModule } from "@angular/core";
import { UserprofileModule } from "./userprofile.component";

@Component({
  selector: "app-root",
  template: `
    <app-userprofile
      name="John"
      [age]="20"
      [favouriteColors]="['green', 'blue', 'red']"
      [isAvailable]="true"
    >
    </app-userprofile>
  `,
})
export class AppComponent {}

@NgModule({
  declarations: [AppComponent],
  imports: [UserprofileModule],
  bootstrap: [AppComponent],
})
export class AppModule {}

Vue 2

<template>
  <UserProfile
    name="John"
    :age="20"
    :favorite-colors="['green', 'blue', 'red']"
    is-available
  />
</template>

<script>
import UserProfile from "./UserProfile.vue";

export default {
  components: {
    UserProfile,
  },
};
</script>

Emit to parent

Angular

import { Component, NgModule } from "@angular/core";
import { AnswerButtonModule } from "./answer-button.component";

@Component({
  selector: "app-root",
  template: `
    <p>Are you happy?</p>

    <app-answer-button (yes)="onAnswerYes()" (no)="onAnswerNo()">
    </app-answer-button>

    <p style="font-size: 50px">{{ isHappy ? "😀" : "😥" }}</p>
  `,
})
export class AppComponent {
  isHappy = true;

  onAnswerYes() {
    this.isHappy = true;
  }

  onAnswerNo() {
    this.isHappy = false;
  }
}

@NgModule({
  declarations: [AppComponent],
  imports: [AnswerButtonModule],
  bootstrap: [AppComponent],
})
export class AppModule {}

Vue 2

<template>
  <div>
    <p>Are you happy?</p>
    <AnswerButton @yes="onAnswerYes" @no="onAnswerNo" />
    <p style="font-size: 50px">
      {{ isHappy ? "😀" : "😥" }}
    </p>
  </div>
</template>

<script>
import AnswerButton from "./AnswerButton.vue";
export default {
  components: {
    AnswerButton,
  },
  data() {
    return {
      isHappy: true,
    };
  },
  methods: {
    onAnswerNo() {
      this.isHappy = false;
    },
    onAnswerYes() {
      this.isHappy = true;
    },
  },
};
</script>

Slot

Angular

import { Component, NgModule } from "@angular/core";
import { FunnyButtonModule } from "./funny-button.component";

@Component({
  selector: "app-root",
  template: `<app-funny-button>Click me!</app-funny-button>`,
})
export class AppComponent {}

@NgModule({
  declarations: [AppComponent],
  imports: [FunnyButtonModule],
  bootstrap: [AppComponent],
})
export class AppModule {}

Vue 2

<template>
  <FunnyButton> Click me! </FunnyButton>
</template>

<script>
import FunnyButton from "./FunnyButton.vue";
export default {
  components: {
    FunnyButton,
  },
};
</script>

Slot fallback

Angular

import { Component, NgModule } from "@angular/core";

@Component({
  selector: "app-root",
  template: `
    <app-funny-button></app-funny-button>

    <app-funny-button>
      <ng-template #content>I got content!</ng-template>
    </app-funny-button>
  `,
})
export class AppComponent {}

@NgModule({
  declarations: [AppComponent],
  imports: [FunnyButtonModule],
  bootstrap: [AppComponent],
})
export class AppModule {}

Vue 2

<template>
  <div>
    <FunnyButton />
    <FunnyButton> I got content! </FunnyButton>
  </div>
</template>

<script>
import FunnyButton from "./FunnyButton.vue";
export default {
  components: {
    FunnyButton,
  },
};
</script>

Context

Angular

import { Component, NgModule } from "@angular/core";
import { UserService } from "./user.service";
import { UserProfileModule } from "./user-profile.component";

@Component({
  providers: [UserService],
  selector: "app-root",
  template: `
    <h1>Welcome back, {{ userService.user.username }}</h1>
    <app-user-profile />
  `,
})
export class AppComponent {
  constructor(public userService: UserService) {}
}

@NgModule({
  declarations: [AppComponent],
  imports: [UserProfileModule],
  bootstrap: [AppComponent],
})
export class AppModule {}

Vue 2

<template>
  <div>
    <h1>Welcome back, {{ user.username }}</h1>
    <UserProfile />
  </div>
</template>

<script>
import UserProfile from "./UserProfile.vue";

export default {
  components: { UserProfile },
  provide() {
    return {
      user: Object.assign(this.user, {
        updateUsername: this.updateUsername,
      }),
    };
  },
  data() {
    return {
      user: {
        id: 1,
        username: "unicorn42",
        email: "unicorn42@example.com",
      },
    };
  },
  methods: {
    updateUsername(newUsername) {
      this.user.username = newUsername;
    },
  },
};
</script>

Form input

Input text

Angular

import { Component, NgModule } from "@angular/core";
import { FormsModule } from "@angular/forms";

@Component({
  selector: "app-input-hello",
  template: `
    <p>{{ text }}</p>
    <input [(ngModel)]="text" />
  `,
})
export class InputHelloComponent {
  text = "";
}

@NgModule({
  declarations: [InputHelloComponent],
  imports: [FormsModule],
  exports: [InputHelloComponent],
})
export class InputHelloModule {}

Vue 2

<template>
  <div>
    <p>{{ text }}</p>
    <input v-model="text" />
  </div>
</template>

<script>
export default {
  data() {
    return {
      text: "Hello World",
    };
  },
};
</script>

Checkbox

Angular

import { Component, NgModule } from "@angular/core";
import { FormsModule } from "@angular/forms";

@Component({
  selector: "app-is-available",
  template: `
    <input id="is-available" type="checkbox" [(ngModel)]="isAvailable" />
    <label for="is-available">Is available</label>
  `,
})
export class IsAvailableComponent {
  isAvailable = false;
}

@NgModule({
  declarations: [IsAvailableComponent],
  imports: [FormsModule],
  exports: [IsAvailableComponent],
})
export class IsAvailableModule {}

Vue 2

<template>
  <div>
    <input id="is-available" v-model="isAvailable" type="checkbox" />
    <label for="is-available">Is available</label>
  </div>
</template>

<script>
export default {
  data() {
    return {
      isAvailable: true,
    };
  },
};
</script>

Radio

Angular

import { Component, NgModule } from "@angular/core";
import { FormsModule } from "@angular/forms";

@Component({
  selector: "app-pick-pill",
  template: `
    <div>Picked: {{ picked }}</div>

    <input id="blue-pill" type="radio" value="blue" [(ngModel)]="picked" />
    <label for="blue-pill">Blue pill</label>

    <input id="red-pill" type="radio" value="red" [(ngModel)]="picked" />
    <label for="red-pill">Red pill</label>
  `,
})
export class PickPillComponent {
  picked = "red";
}

@NgModule({
  declarations: [PickPillComponent],
  imports: [FormsModule],
  exports: [PickPillComponent],
})
export class PickPillModule {}

Vue 2

<template>
  <div>
    <div>Picked: {{ picked }}</div>

    <input id="blue-pill" v-model="picked" type="radio" value="blue" />
    <label for="blue-pill">Blue pill</label>

    <input id="red-pill" v-model="picked" type="radio" value="red" />
    <label for="red-pill">Red pill</label>
  </div>
</template>

<script>
export default {
  data() {
    return {
      picked: "red",
    };
  },
};
</script>

Select

Angular

import { Component, NgModule } from "@angular/core";
import { FormsModule } from "@angular/forms";

@Component({
  selector: "app-color-select",
  template: `
    <select [(ngModel)]="selectedColorId">
      <option
        *ngFor="let color of colors"
        [value]="color.id"
        [disabled]="color.isDisabled"
      >
        {{ color.text }}
      </option>
    </select>
  `,
})
export class ColorSelectComponent {
  selectedColorId = 2;

  colors = [
    { id: 1, text: "red" },
    { id: 2, text: "blue" },
    { id: 3, text: "green" },
    { id: 4, text: "gray", isDisabled: true },
  ];
}

@NgModule({
  declarations: [ColorSelectComponent],
  imports: [FormsModule],
  exports: [ColorSelectComponent],
})
export class ColorSelectModule {}

Vue 2

<template>
  <select v-model="selectedColorId">
    <option
      v-for="color in colors"
      :key="color.id"
      :value="color.id"
      :disabled="color.isDisabled"
    >
      {{ color.text }}
    </option>
  </select>
</template>

<script>
export default {
  data() {
    return {
      selectedColorId: 2,
      colors: [
        { id: 1, text: "red" },
        { id: 2, text: "blue" },
        { id: 3, text: "green" },
        { id: 4, text: "gray", isDisabled: true },
      ],
    };
  },
};
</script>

Webapp features

Render app

Angular

<!DOCTYPE html>
<html>
  <body>
    <app-root></app-root>
  </body>
</html>

Vue 2

<!DOCTYPE html>
<html>
  <body>
    <div id="app"></div>
    <script type="module" src="./main.js"></script>
  </body>
</html>

Fetch data

Angular

import { HttpClient } from "@angular/common/http";
import { Injectable } from "@angular/core";
import { BehaviorSubject } from "rxjs";

export interface UsersState {
  users: User[];
  error: string | null;
  loading: boolean;
}

export const initialState: UsersState = {
  users: [],
  error: null,
  loading: false,
};

@Injectable({ providedIn: "root" })
export class UserService {
  private state = new BehaviorSubject<UsersState>(initialState);
  state$ = this.state.asObservable();

  constructor(private http: HttpClient) {}

  loadUsers() {
    this.state.next({ ...initialState, loading: true });

    this.http
      .get<UserResponse>("https://randomuser.me/api/?results=3")
      .subscribe({
        next: ({ results }) =>
          this.state.next({ ...initialState, users: results }),
        error: (error) => this.state.next({ ...initialState, error }),
      });
  }
}

export interface UserResponse {
  results: User[];
  info: any;
}

export interface User {
  name: {
    title: string;
    first: string;
    last: string;
  };
  picture: {
    large: string;
    medium: string;
    thumbnail: string;
  };
}

Vue 2

<template>
  <p v-if="isLoading">Fetching users...</p>
  <p v-else-if="error">An error ocurred while fetching users</p>
  <ul v-else-if="users">
    <li v-for="user in users" :key="user.login.uuid">
      <img :src="user.picture.thumbnail" alt="user" />
      <p>
        {{ user.name.first }}
        {{ user.name.last }}
      </p>
    </li>
  </ul>
</template>

<script>
export default {
  data() {
    return {
      isLoading: false,
      error: undefined,
      users: undefined,
    };
  },
  mounted() {
    this.fetchData();
  },
  methods: {
    async fetchData() {
      this.isLoading = true;
      try {
        const response = await fetch("https://randomuser.me/api/?results=3");
        const { results: users } = await response.json();
        this.users = users;
        this.error = undefined;
      } catch (error) {
        this.error = error;
      } finally {
        this.users = undefined;
        this.isLoading = false;
      }
    },
  },
};
</script>