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Validating in javascript

validating in javascript-7

Reading and copying selected text to clipboard using Java Script In this tutorial, we'll see how to read the textual contents of a user selection, dynamically select some text on the page, and last but not least, copy whatever is selected to clipboard, all using just Java Script. Beginner's Guide to Java Script Promises Java Script Promises are a new addition to ECMAscript 6 that aims to provide a cleaner, more intuitive way to deal with the completion (or failure) of asynchronous tasks.In this tutorial we'll deliver the promise of Java Script Promises to the uninitiated!

This includes a large bunch of sample code and a complete reference guide to all the built-in validation rules in the library.If you imagine form as a dialog between your website and your user, the messages play an important role.Don’t leave it to the auto-generated default messages.If they don't properly escape when inserting into SQL, any name with an apostrophe (which your original question already recognizes as necessary) opens you up to security vulnerabilities.Imagine trying to authenticate a user nameed "Foo'or True Or'foo" — no "dangerous" characters, but there goes your login scheme.If you skip the message for a validation, the default message is displayed.

See a complete demo @Codepen The messages parameter is optional.

If all you're doing is reading and writing to the db, then properly parameterizing queries should take care of the problem.

However, if you're ever going to dynamically execute code from the db, then you have to be careful (such as using the exec() statement.

See how to take advantage of this method in this comprehensive tutorial.

Determining how much the user has scrolled the page using Java Script or j Query Learn how to detect the amount the user has scrolled the page using Java Script or j Query, in either pixels travelled or as a percentage of the whole page.

Explain to your user what is wrong and suggest solutions.