Question

5

Angular 2 - Bindings cannot contain assignments

rated 0 times [ 9] [ 4] / answers: 1 / hits: 47038 / 7 Years ago, thu, march 30, 2017, 12:00:00

I need to give a class to a <tr> if a property of item has the same value as a property from an object in an array.

Here's the code I currently have:

<tr *ngFor=let item of closingDayGroupsList [class.inactive]=definitionDetails.Groups.filter(i => i.AbsenceReservationGroupID === item.ID).length > 0>

however now I receive the error:

Bindings cannot contain assignments

I'm not sure if what I'm doing is bad practice, or if I'm just making syntax errors.

This is the only way I know to achieve what I want, but it's not working

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aliah

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4 Years ago

answered 7 Years ago jackie · Accepted Answer

Its a bad practice to use expressions in angular bindings

Move the class expression into controller.

export class AppComponent {

    title = 'Groups';



    getClass(item): void {



      // add filter logic here

      return this.definitionDetails.Groups.filter(i => i.AbsenceReservationGroupID === item.ID).length > 0



    }

}

The tr will be something like,

<tr *ngFor=let item of closingDayGroupsList [class.inactive]=getClass(item)>