Repeat HTML element multiple times using ngFor based on a number

Source: https://stackoverflow.com/questions/36535629/repeat-html-element-multiple-times-using-ngfor-based-on-a-number

<ng-container *ngFor="let i of [].constructor(20)">🐱</ng-container>

How to use select/option/NgFor on an array of objects in Angular2

Source: https://stackoverflow.com/questions/33181936/how-to-use-select-option-ngfor-on-an-array-of-objects-in-angular2

I don't know what things were like in the alpha, but I'm using beta 12 right now and this works fine. If you have an array of objects, create a select like this:

<select [(ngModel)]="simpleValue"> // value is a string or number
    <option *ngFor="#obj of objArray" [value]="obj.value">{{obj.name}}</option>
</select>

If you want to match on the actual object, I'd do it like this:

<select [(ngModel)]="objValue"> // value is an object
    <option *ngFor="#obj of objArray" [ngValue]="obj">{{obj.name}}</option>
</select>

NgFor examples

Source: https://www.concretepage.com/angular-2/angular-2-ngfor-example

<b> *ngFor Demo</b>
<ul>
 <li *ngFor="let user of users">
  {{user.name}} - {{user.age}}
 </li>
</ul>

<b> ngFor with template Attribute </b>
<ul>
<li template = "ngFor let user of users; let i = index">
  Row {{i}} : {{user.name}} - {{user.age}}
</li>
</ul>

<b> ngFor with template Tag </b>
<ul>
 <template ngFor let-user [ngForOf] = "users"  let-i = "index">
   <li>  Row {{i}} : {{user.name}} - {{user.age}} </li>
 </template>
</ul>

<b>index variable demo </b>
 <p *ngFor="let user of users; let i = index">
  Row {{i}} : Name: {{user.name}}
 </p>

 <b>first and last variable demo </b>
 <div *ngFor="let user of users; let i = index; let f=first; let l=last;">
  Row {{i}} : Name: {{user.name}}, is first row: {{f}}, is last row: {{l}}
 </div>

 <b>even and odd variable demo </b>
 <div *ngFor="let user of users; let i = index; let e=even; let o=odd;">
  Row {{i}} : Name: {{user.name}}, is even row: {{e}}, is odd row: {{o}}
 </div>

<br/><b>ngFor with component element using *ngFor</b>
<emp-app *ngFor="let user of users" [emp]="user"> </emp-app>

<br/><b>ngFor with component element using template directive </b>
<emp-app template="ngFor let user of users" [emp]="user"> </emp-app>

<br/><b>ngFor with component element using template tag </b>
<template ngFor let-user [ngForOf]="users">
  <emp-app [emp]="user"></emp-app>
</template> 

ngFor with index as value in attribute

Source: https://stackoverflow.com/questions/35405618/ngfor-with-index-as-value-in-attribute

<ul>
    <li *ngFor="let item of items; let i = index" [attr.data-index]="i">
        {{item}}
    </li>
</ul>