Form validation is an essential part of creating user-friendly and secure web applications. Often, different users may require custom validation rules based on their roles or preferences. In this blog post, we will explore how to use session storage to manage user-specific form validation rules in JavaScript.

What is Session Storage?

Session storage is a web storage API that allows you to store key-value pairs in the browser’s session scope. Unlike local storage, which persists data even after the browser is closed, session storage only lasts for the duration of the user’s session. This makes it ideal for storing temporary data, such as user-specific form validation rules.

Setting Up the Session Storage

To get started, we need to set up the session storage and store the user-specific validation rules. Assuming you have already collected the validation rules from the user, you can store them in the session storage as follows:

// Store user-specific validation rules
sessionStorage.setItem('validationRules', JSON.stringify(validationRules));

Here, validationRules is an object containing the validation rules for the user. We convert it to a JSON string using JSON.stringify() before storing it in the session storage.

Retrieving the Validation Rules

Once the validation rules are stored in the session storage, we can retrieve them when needed. To do this, we need to parse the JSON string back into an object:

// Retrieve user-specific validation rules
const validationRules = JSON.parse(sessionStorage.getItem('validationRules'));

With the validation rules now in the validationRules object, we can use them to dynamically apply custom form validation.

Applying Custom Form Validation

To apply the custom form validation rules, we need to iterate over the validation rules object and assign the appropriate validation functions to the form fields. Here is an example of how this can be done:

// Iterate over validation rules and apply custom validation
for (const field in validationRules) {
  if (validationRules.hasOwnProperty(field)) {
    const inputField = document.getElementById(field);
    const validationFunction = validationRules[field];
    inputField.addEventListener('input', validationFunction);
  }
}

In the above example, we assume that the form fields have unique IDs corresponding to the keys in the validation rules object. We retrieve each field using document.getElementById() and assign the corresponding validation function stored in validationRules[field] to the input event listener. This will trigger the custom validation function whenever the user interacts with the form field.

Conclusion

By using session storage, we can easily manage user-specific form validation rules in our JavaScript applications. This allows us to provide a more personalized and secure user experience. Remember to clear the session storage when the user logs out or the session expires to ensure data integrity.

#JavaScript #FormValidation #SessionStorage