Other form values are available using a similar syntax, although this becomes more complicated if you're using SELECT lists, checkboxes or radio buttons (see below for examples). All you need to do is extend the command is encountered, execution of the function is halted.
When the form is submitted - either by hitting Enter or clicking on the Submit button - the (the 'value' of the field called 'input' belonging to the form). In a real-life situation you will most likely have more fields to check, and more complicated conditions, but the principle remains the same.
If not enough, use the awesome Parsley extra Ajax validator or tons of other extended validators provided by the community.
to avoid any erroneous data to be inserted into the database. So let us learn some basics because I have written this article only focusing on beginners and students. Example I hope you now understand the basics of validation in Java Script, now let us create the one sample web application that demonstrates how to do validation.
It can prevent people from leaving fields blank, from entering too little or too much or from using invalid characters.
For an alternative approach to client-side form validation, without Java Script, check out our new article on HTML5 Form Validation which is available now in most modern browsers.