In this case, we've created a stand-alone functions which will validate a date field: In each case the value passed to the function is the form field rather than the field value.
The output will be almost identical to the earlier examples.
As we've seen before, creating re-usable functions can significantly reduce the size of your Java Script code.
The time field will allow input starting with 'hh:mm' following by an optional 'am' or 'pm'. The code behind the form is as follows: For each field in the form (first the dates, then the time field), a check is made as to whether the input is blank.
If not, the input is compared to the regular expression.
In this simple example we can even rewrite the In practice most modern browsers will now use HTML form validation to preempt any Java Script validation - with the notable exception of Safari. Visitors from some countries may find it confusing that we're using the and vice-versa as the year and day values have now changed position.
In Java Script to check for different month lengths, particularly for February in leap years, you need quite a bit of extra code.
Instead we're going to make use of Form Validation using Ajax to do some real-time checking using a server-side PHP script to get a definitive answer. It was more interesting than reading Sherlock Holmes stories.These were real-life incidents, real lessons learned, and real actions taken. tag: content 80% of the end-user response time is spent on the front-end.Most of this time is tied up in downloading all the components in the page: images, stylesheets, scripts, Flash, etc.The function has been improved now so that the day, month and year values are checked to ensure that they're in the right ball-bark (ie. Also the year must be between 1902 and the current year.The year limitation would be used if you were asking for a date of birth or date of some recent event.A related type of attack, ‘login CSRF’, where an attacking site tricks a user’s browser into logging into a site with someone else’s credentials, is also covered.When capturing information for insertion into a database, or use in other processing, it's important to control what the user can enter.When you enter a date in the format dd/mm/yyyy the value is sent via an Ajax call to the server where it is validated using the PHP checkdate function. The return value is displayed next to the input field: Other actions could also be taken such as disabling form submission until there is a valid date.