Struggling to retrieve an Object from an HTMLSelectElement within an Angular project

Question

Struggling to retrieve an Object from an HTMLSelectElement within an Angular project

Can you help me with this code snippet:

<select #categorySelect (change)="goToCategory.emit(categorySelect.value)" style="...">
    <option selected hidden>All</option>    
    <option 
        [ngValue]="category" 
        *ngFor="let category of categories">
            {{category.groupName}}
        </option>
</select>

@Output() goToCategory = new EventEmitter<Category>();

I am facing an issue where I am getting the string 'object Object' instead of the actual object category. Is there a way to modify the code so that I can get the object element for the function in '(change)'?

javascript angular typescript

Answer 1

Answer №1

Consider implementing a method within the component to emit the object value instead of doing it directly from the template:

Here's a suggestion:

Create a new helper method called getCategory, where you can set the category.id as an option value for easy reference later:

<select #categorySelect (change)="getCategory(categorySelect.value)" style="...">


[value]="category.id"

Add a new method that locates the object and emits it from there:

  getCategory(id:string) {
    
    const categorySelect = this.categories.find(el=>el.id === id);

    this.goToCategory.emit(categorySelect);
  }

You may also want to utilize ngModel:

<select [(ngModel)]="categorySelect" (change)="goToCategory.emit(categorySelect)" style="...">

// need to tweak default selected..
categorySelect:Category= this.categories[0]; // or 'All'

Answer 2

Consider implementing a method within the component to emit the object value instead of doing it directly from the template:

Here's a suggestion:

Create a new helper method called getCategory, where you can set the category.id as an option value for easy reference later:

<select #categorySelect (change)="getCategory(categorySelect.value)" style="...">


[value]="category.id"

Add a new method that locates the object and emits it from there:

  getCategory(id:string) {
    
    const categorySelect = this.categories.find(el=>el.id === id);

    this.goToCategory.emit(categorySelect);
  }

You may also want to utilize ngModel:

<select [(ngModel)]="categorySelect" (change)="goToCategory.emit(categorySelect)" style="...">

// need to tweak default selected..
categorySelect:Category= this.categories[0]; // or 'All'

Answer 3

Answer №2

To make your category object usable in a select, it needs to be serialized into a string value. Here's how you can do it:

[ngValue]="JSON.stringify(category)"

When you need to access the category data (for example, in the method triggered by your Output), simply deserialize the string back into an object like this:

handleSerializedCategory(serializedCategory:string){    
let category = JSON.parse(serializedCategory) as Category;

//Perform actions on the category object
}

Answer 4

To make your category object usable in a select, it needs to be serialized into a string value. Here's how you can do it:

[ngValue]="JSON.stringify(category)"

When you need to access the category data (for example, in the method triggered by your Output), simply deserialize the string back into an object like this:

handleSerializedCategory(serializedCategory:string){    
let category = JSON.parse(serializedCategory) as Category;

//Perform actions on the category object
}

Struggling to retrieve an Object from an HTMLSelectElement within an Angular project

Answer №1

Answer №2

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