angularjs - How to track the last Variable of *ngFor in the ngForTrackBy function of Angular 2 -

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if use *ngfor="let item of items; let = index; let islast=last" value of islast in ui using {{islast}}. if use ngfortrackby: myfunction , function support index:number , obj : contains value of item.

so how 1 "last" variable stated in https://angular.io/docs/ts/latest/api/common/index/ngfor-directive.html in custom ngfortrackby function? possible?

is there way track *ngfor completed rendering, can limit number of row shown scroll-able window?


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