Entering a value into the arrival Date field triggers the input event.The Java Script code adds an event listener for the input event and checks whether the date entered is greater than the current date.If you don’t enter a value then the regular expression is never triggered.You need to include the required attribute to force a user to enter a value and cause the value to be validated against the regular expression.If validation fails then the validation error message “Arrival date must be after now!” is assigned to the arrival Date input field by calling the set Custom Validity() method of the validation constraint API.Finally, we discuss the security issues related to using client-side validation.The HTML5 specification discusses several attributes which you can use with INPUT elements to perform client-side validation including the required, pattern, min, max, step, and maxlength attributes.
From the perspective of HTML5 validation, the h5Validate plugin is the best of the plugins.
The only requirement is that you write a Java Script function.
For example, when booking a hotel room, you might want to validate that the Arrival Date is in the future instead of the past: The form above contains an input field named arrival Date.
You can take advantage of the HTML5 constraint validation API to perform custom validation.
You can perform any custom validation that you need.