Vue Form Validation With Regex

This Vue.js application demonstrates dynamic form validation using regex patterns, providing real-time feedback as users type. It validates name and email fields, displaying error messages instantly without waiting for form submission. The form integrates with Firebase for data persistence, adding/removing users reactively. Dynamic validation enhances user experience by catching errors early, guiding corrections, and preventing invalid submissions. Benefits include reduced frustration, improved data quality, and a more interactive interface compared to traditional submit-time validation.

Dynamic Validation in Action

The app uses Vue’s computed properties for live validation:

computed: {
  validation: function () {
    return {
      name: !!this.newUser.name.trim(),
      email: emailRE.test(this.newUser.email)
    }
  },
  isValid: function () {
    return Object.keys(this.validation).every(key => this.validation[key])
  }
}

Regex checks email format:

var emailRE = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/

Errors show conditionally:

<ul class="errors">
  <li v-show="!validation.name">Name cannot be empty.</li>
  <li v-show="!validation.email">Please provide a valid email address.</li>
</ul>

Submit only proceeds if valid.

Benefits of Dynamic Validation

Instead of waiting for submit:

• Immediate Feedback: Users see issues as they type, correcting quickly.
• Better UX: Reduces form abandonment; feels responsive.
• Error Prevention: Catches invalid data early, improving quality.
• Accessibility: Screen readers announce changes instantly.
• Performance: Client-side validation avoids server round-trips for basic checks.

This approach works for complex forms, using regex for patterns like emails, phones, or custom rules.

Implementation with Vue

Vue’s reactivity makes dynamic validation simple. Bind inputs with v-model, compute validation state, and show messages with v-show. For server validation, combine with async checks.

This demo integrates Firebase for real-time data sync, showcasing full-stack reactive apps. Dynamic validation is a key pattern for modern web forms.