Often, we perform basic checks on user input controls before they’re ready for data validation and submission. For example, a form might enable the submit button only after the user fills in a specific number of fields, or the user needs to enter data correctly to proceed to the next step.
This helps reduce submission errors and ensures users can submit their information with minimal complications. Real-time feedback enhances this approach.
CSS enables certain simple checks before the browser’s validation process is triggered during submission. The :valid and :invalid pseudo-classes are perfect illustrations of this, allowing browsers to style fields during input to indicate proper format.
Similarly, the n of syntax in the :nth-child selector is beneficial for initial validation. First, let’s explore its function.
About n of selectors
The :nth-child() selector counts elements from the start among all siblings. The n of selectors variant counts only those matching the specified selectors.
:nth-child(2) { }
:nth-child(2 of .marked) { }Code language: CSS (css)While not specifically designed for it, n of selectors can somewhat track the number of matching elements. The same concept applies to pseudo-classes indicating element states.
label:nth-child(2 of <span class