Angular 2 - NgFor using numbers instead collections

...for example...

<div class="month" *ngFor="#item of myCollection; #i = index">
...
</div>

Is possible to do something like...

<div class="month" *ngFor="#item of 10; #i = index">
...
</div>

...without appeal to a non elegant solution like:

<div class="month" *ngFor="#item of ['dummy','dummy','dummy','dummy','dummy',
'dummy','dummy','dummy']; #i = index">
...
</div>

Within your component, you can define an array of number (ES6) as described below:

export class SampleComponent {
  constructor() {
    this.numbers = Array(5).fill().map((x,i)=>i); // [0,1,2,3,4]
    this.numbers = Array(5).fill(4); // [4,4,4,4,4]
  }
}

See this link for the array creation: Tersest way to create an array of integers from 1..20 in JavaScript.

You can then iterate over this array with ngFor:

@Component({
  template: `
    <ul>
      <li *ngFor="let number of numbers">{{number}}</li>
    </ul>
  `
})
export class SampleComponent {
  (...)
}

Or shortly:

@Component({
  template: `
    <ul>
      <li *ngFor="let number of [0,1,2,3,4]">{{number}}</li>
    </ul>
  `
})
export class SampleComponent {
  (...)
}

@OP, you were awfully close with your "non-elegant" solution.

How about:

<div class="month" *ngFor="let item of [].constructor(10); let i = index"> ... </div>

Here I'm getting the Array constructor from an empty array: [].constructor, because Array isn't a recognized symbol in the template syntax, and I'm too lazy to do Array=Array or counter = Array in the component typescript like @pardeep-jain did in his 4th example. And I'm calling it without new because new isn't necessary for getting an array out the Array constructor.

Array(30) and new Array(30) are equivalent.

The array will be empty, but that doesn't matter because you really just want to use i from ;let i = index in your loop.

No there is no method yet for NgFor using numbers instead collections, At the moment, *ngFor only accepts a collection as a parameter, but you could do this by following methods:

Using pipe

demo-number.pipe.ts:

import {Pipe, PipeTransform} from 'angular2/core';

@Pipe({name: 'demoNumber'})
export class DemoNumber implements PipeTransform {
  transform(value, args:string[]) : any {
    let res = [];
    for (let i = 0; i < value; i++) {
        res.push(i);
      }
      return res;
  }
}

For newer versions you'll have to change your imports and remove args[] parameter:

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({name: 'demoNumber'})
export class DemoNumber implements PipeTransform {
  transform(value) : any {
    let res = [];
    for (let i = 0; i < value; i++) {
        res.push(i);
      }
      return res;
  }
}

html:

<ul>
  <li>Method First Using PIPE</li>
  <li *ngFor='let key of 5 | demoNumber'>
    {{key}}
  </li>
</ul>

Using number array directly in HTML(View)

<ul>
  <li>Method Second</li>
  <li *ngFor='let key of  [1,2]'>
    {{key}}
  </li>
</ul>

Using Split method

<ul>
  <li>Method Third</li>
  <li *ngFor='let loop2 of "0123".split("")'>{{loop2}}</li>
</ul>

Using creating New array in component

<ul>
  <li>Method Fourth</li>
  <li *ngFor='let loop3 of counter(5) ;let i= index'>{{i}}</li>
</ul>

export class AppComponent {
  demoNumber = 5 ;
  
  counter = Array;
  
  numberReturn(length){
    return new Array(length);
  }
}

#Working demo

Angular 2 - NgFor using numbers instead collections

Using pipe

Using number array directly in HTML(View)

Using Split method

Using creating New array in component

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