Angular: conditional class with *ngClass

🔥 Angular: Conditional Class with *ngClass 🔥

So, you're using Angular and trying to conditionally add a class to an element using the *ngClass directive, but you're encountering an error message like:

Cannot read property 'remove' of undefined at BrowserDomAdapter.removeClass

Don't worry, I've got your back! Let's dive into this issue and find an easy solution together! 💪

The Problem: Understanding the Error Message

First, let's decode the error message. It seems to mention something about BrowserDomAdapter.removeClass, which could be related to the template code you shared.

The error message usually occurs when Angular tries to remove a class from an element but encounters an undefined object. 🤔

The Solution: Fixing the Error

The issue in your code lies within the *ngClass directive. 💡

To conditionally add or remove a class using *ngClass, you need to provide an object where the keys represent the class names, and the values determine whether the class should be added or removed.

In your code snippet, the object is {active: step==='step1'}. This means that the class active should be added if the condition step==='step1' is true.

However, the error occurs because the step variable is undefined. 😱

To fix this, make sure to declare and initialize the step variable in your component TypeScript code:

step: string = 'step1'; // or any default value you prefer

💡Pro Tip: When using *ngClass or any other Angular directive, ensure that the associated variables are correctly defined and initialized.

Once you've declared and initialized the step variable, Angular won't encounter the undefined error anymore, and your code should work like a charm! 🎉

Take It Further: Advanced Usage

If you want to add multiple classes conditionally, you can do so by extending the object in the *ngClass directive. Here's an example:

<div [ngClass]="{ 'class1': condition1, 'class2': condition2, 'class3': condition3 }">
  <!-- Your HTML content here -->
</div>

This way, each class will be added based on its corresponding condition.

Your Turn: Engage and Share!

Now that you understand how to fix the error and use conditional classes with *ngClass, it's time to put your new knowledge into action! ✨

Why not share this blog post with your fellow Angular developers who might be facing a similar issue? Let's help them code without any errors!

Feel free to leave a comment below if you have any questions or want to share your own experiences with conditional classes. 😊

Happy coding! 💻✨