what is the best approach to create a prompt to asking input username & password by using Javascript

what is the best approach to using javascript to asking input username & password in a singl开发者_JAVA百科e prompt window?(multiple input field)

There is a prompt() function that you can use. You can also use something like jQuery UI to create a more fancy dialog. Make sure that it's the backend server that's checking it using AJAX though. Don't store the password in the Javascript as it will be trivial just checking the source code to circumvent it.

You can create dialog boxes of arbitrary complexity with jQuery UI [other JavaScript UI libraries may exist].