Angular: Hide HTML Attribute When Input is Empty

I have a scenario in my Component where we need to input an HTML attribute.

But if no value is provided for the input, I want to completely hide the attribute in the HTML. Is there a way to achieve this without displaying it as an empty string?

export class ProductComponent implements OnInit {

  @Input dataQA: string;

HTML:

<div class="productTitle"
    data-qa="dataQA"
>

Note: My goal is to retain the entire div structure while excluding specific attributes within it. There may be multiple attributes added in the future, so I am seeking an efficient solution to handle this.

angulartypescriptangular10

Answer №1

If you want to conditionally display content, you can use 

*ngIf="<condition>"

For instance: 

<div class="productTitle" data-qa="dataQA" *ngIf="dataQa">

To dynamically apply an attribute, you can use attribute bindings in a similar way:

For example: 

<p [attr.dataQA]="something ? null : ''">

Explanation: null will prevent the attribute from being applied, while '' (an empty string) will apply the attribute without a value (e.g., dataQA instead of dataQA="some value")

If you have a string in your case, it would look like this:

<p [attr.test]="something ? something : null">

Learn more about NgIf on angular.io

Check out the guide on attribute binding

Here's a working example: View on StackBlitz

Answer №2

To incorporate a conditional check, you can utilize the ngIf directive. In order to meet your specific needs, consider including two distinct HTML elements - one with an attribute and one without. Then proceed to implement a condition based on these elements.

Give this a try:

<div class="productName" [attr.data-custom]="customData || null"></div>

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