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javascript - How to set default value for drop-down multiselect in angular 2 and ngprime - Stack Overflow

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I am following PrimeNg Example .and here is a Plunker.How can I make some values pre selected in the drop down.

  <p-multiSelect [options]="cities" [(ngModel)]="selectedCities"></p-multiSelect>

I am following PrimeNg Example .and here is a Plunker.How can I make some values pre selected in the drop down.

  <p-multiSelect [options]="cities" [(ngModel)]="selectedCities"></p-multiSelect>
Share Improve this question edited Sep 26, 2017 at 11:39 zgue 3,8509 gold badges36 silver badges40 bronze badges asked Sep 26, 2017 at 11:32 Mukul SharmaMukul Sharma 1762 gold badges5 silver badges20 bronze badges 1
  • You might have a look at How to set default value for PrimeNG p-dropdown. – Murat Yıldız Commented Sep 12, 2018 at 7:49
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3 Answers 3

Reset to default 11

You only need to attach an array of values to selectedCities variable in order to bind this to the model.

In your case the value property is an object which contains many properties.

value:{id:1, name: 'New York', cityCode: 'NY'}

The solution is to map the array items in order to obtain the values you want.

For instance, this will preselect the fist two items from your dropdown element.

this.selectedCities = this.cities.slice(0,2).map(a => a.value));

If you want to preselect values from a given array, you should use filter method.

let arrayOfValues=['NY','IST'];
this.selectedCities = this.cities.filter(a => arrayOfValues.includes(a.value.cityCode)).map(a => a.value));

The selected cities are stored in the selectedCities array. Since it's a two-way binding, just populate that arry, it will get reflected in the view.

import {SelectItem} from 'primeng/primeng';

let cities: SelectItem[] = [
    { label : "Rome"     , value : "ro" },
    { label : "London"   , value : "lo" },
    { label : "Paris"    , value : "pa" },
    { label : "New York" , value : "ny" }
]

let selectedCities: string[] = ["lo", "ny"] // This will pre-select the cities in your dropdown

There is a good way you can define value for each of your options. Then define the variable selectedCities to the value you want as defult. It will make the angular to choose that vale option on initialization.

let Cities: SelectItem[] = [
    { label : "Rome"     , value : "ro" },
    { label : "London"   , value : "lo" },
    { label : "Paris"    , value : "pa" },
    { label : "New York" , value : "ny" }
]

selectedCity = "ro";

this will set the Selected calue to defult Rome.

(*thanks to Jeremy Thille. I copied a part of my code from you.)

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