How to Validate Ionic 2 Radio Button Selections with TypeScript

Imagine having a list like the one shown below:

<ion-list radio-group [(ngModel)]="autoManufacturers">
  <ion-list-header>
    Auto Manufacturers
  </ion-list-header>

  <ion-item>
    <ion-label>Cord</ion-label>
    <ion-radio value="cord"></ion-radio>
  </ion-item>

  <ion-item>
    <ion-label>Duesenberg</ion-label>
    <ion-radio value="duesenberg"></ion-radio>
  </ion-item>

  <ion-item>
    <ion-label>Hudson</ion-label>
    <ion-radio value="hudson"></ion-radio>
  </ion-item>
</ion-list>

If a particular value is retrieved from the database, I would like to have the corresponding item in the list checked. For example, if the value 'cord' is obtained, then the second item should be displayed as the selected item. How can I accomplish this using TypeScript?

angulartypescriptionic-frameworkionic2ionic3

Answer №1

When connecting the radio group to the autoManufacturers property in your Component, simply assign the value retrieved from the database to that property:

// In a section of your code
this.autoManufacturers = valueFromDataBase; // where valueFromDataBase === 'cord'

By doing this, the option with the cord value will be automatically selected.

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