How to prevent the page from refreshing after validation?

Question

I have a registration form wherein one of the field is username which needs to be unique. So, I am checking it first in my database before insert proceeds. If username exists, I put the below line. My problem is after clicking OK, it refreshes the page and clears all the inputted data of the user. I know I can use return false but how do I put this on my echo?

else if(mysql_num_rows($result)>0)
{
    echo '<script>alert("Username is not available")</script>';
} 
else 
{ 
    insert goes here
    <form id="appform"  action="register.php" method="post" onsubmit="return validateform('appform');">
    <input type="text" class="textarea1" name="stdname" size="30" onkeyup="isallnospace(this)" /> .
}

you've updated the code, where is the isallnospace(this) function ? and you're mixing php and html in one lump — Billy, Dec 31 '15 at 10:42
@Billy function isallnospace(ele) { var r=/\W$/i; if(r.test(ele.value)) { alert("This Field allows Only Alpha Numeric characters."); ele.value=""; ele.focus(); } } — 안젤라, Dec 31 '15 at 10:48
Please [stop using `mysql_*` functions](http://stackoverflow.com/questions/12859942/why-shouldnt-i-use-mysql-functions-in-php). [These extensions](http://php.net/manual/en/migration70.removed-exts-sapis.php) have been removed in PHP 7. Learn about [prepared](http://en.wikipedia.org/wiki/Prepared_statement) statements for [PDO](http://php.net/manual/en/pdo.prepared-statements.php) and [MySQLi](http://php.net/manual/en/mysqli.quickstart.prepared-statements.php) and consider using PDO, [it's really pretty easy](http://jayblanchard.net/demystifying_php_pdo.html). — Jay Blanchard, Dec 31 '15 at 10:51
What you're asking requires that you use AJAX. There is not enough code in your question for anyone to answer any more fully. — Jay Blanchard, Dec 31 '15 at 10:54

Manikiran · Answer 1 · 2015-12-31T10:34:10.597

0

You are validating in the worst way possible. If you want to validate using both client side and server side script, please use ajax.

Uses of Ajax:

Update a web page without reloading the page
Request data from a server - after the page has loaded
Receive data from a server - after the page has loaded
Send data to a server - in the background

For more details, visit AJAX Tutorial

edited Dec 31 '15 at 10:34

answered Dec 31 '15 at 10:30

Manikiran

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it's php that checks, if no submitting then no check – Billy Dec 31 '15 at 10:33
@Manikiran but i already have this for checking other validation onsubmit="return validateform('appform');" – 안젤라 Dec 31 '15 at 10:34
@Manikiran sorry but were only allowed to use js and php – 안젤라 Dec 31 '15 at 10:38
If you want to simplify your work, use Jquery (or Angular Js) and Ajax. It makes your work a lot easier. – Manikiran Dec 31 '15 at 10:41
Here is a jquery and ajax tutorial link: http://www.w3schools.com/jquery/jquery_ajax_intro.asp – Manikiran Dec 31 '15 at 10:42
AJAX is part of JavaScript, not a plugin. – Jay Blanchard Dec 31 '15 at 10:53

score 0 · Answer 2 · edited Dec 31 '15 at 10:54

0

best way is to check with ajax before submit, but if you want you can add the $_POST values to the form when it returns to it like so

<input type="text" name="username" value="<?php if(isset($_POST['username'])){echo $_POST['username'];}?>" />

edited Dec 31 '15 at 10:54

Jay Blanchard

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answered Dec 31 '15 at 10:37

Billy

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How to prevent the page from refreshing after validation?

2 Answers2