Angular: Get current index in ngFor

Question

I have following angular:

    {{item}}




        
                      

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Answer 1

As per OP's comment on question :

So, I am trying to get the index of the ngFor in order to do a comparison to array of data before triggering another function. For example, the test() function will be triggered when I click a button, then it will check the current index, and do something with it.

You should do it like :

<div class="test" *ngFor="let item of data; let i = index">
    // In your case this line should be within ngFor loop
    <div class="function_div" (click)="test(i);">Test Button </div>
    {{item}}
</div>

---

Note : Never call function like :

{{ test(i) }} // this will be executed each time anything changes in loop

Answer 2

You can create your own directive to get the current index on every function call through *ngFor. You can follow this answer.

Answer 3

Why you just not..

<div class="test" *ngFor="let item of data; let i = index">
    {{ test(i) }}
</div>


export class test{

  test(i: number){
     console.log(i);
  }

}

Answer 4

You couls alwasy go the simple way, like that:

    <div *ngFor =" let item of items; let i = index">

          {{ i }} {{ item }}

    </div>