PHP how to not refresh input values after press submit - php

I have problem, when I press submit button in my contact form all input values refreshing, it's good if all fields are filled correct, but if are some warning users must see previaus values, but all are cleared. My Javascript skills are low, maye are solution to solv this problem with php and html ?

a simpler way is use html5 storage . store value on onkeyup event and destroy if submit successful
for an example
<input id="title" type="text" value="" name="article_name">
script
to check support of html5
function supports_html5_storage() {
try {
return 'localStorage' in window && window['localStorage'] !== null;
} catch (e) {
return false;
}
}
script to store
if(supports_html5_storage()){
$("#title").keyup(function(){
var articel_title = $("#title").val();
localStorage.setItem("articel_title",articel_title);
localStorage.getItem("articel_title");
});
to clear storage ,you can fire this if form successfully submit it will clear storage
<script type=text/javascript>
localStorage.removeItem("articel_title");
</script>
you can also make ajax call on change or keyup event and store value to database so that if html5 is not supported by browser it will still work but it will cause more load on server

return values to client:
<input type="text" name="val1" value="<?echo $_POST['val1']?>" />

Post your values to an iframe within the page and if the entries are correct then redirect to another page.
So if the entries are wrong you would not have to do anything

You will need ajax with jquery. The follwoing tutorials will help you:
http://www.queness.com/post/160/create-a-ajax-based-form-submission-with-jquery
http://www.tuttoaster.com/create-an-ajaxjqueryphp-contact-form/

Related

PHP 'beating' javascript function call?

I've got a bit of a weird problem.
I'm creating a location based web app that is using a javascript function to get a user's GPS coordinates. I have a form with a submit button, and when that submit button is clicked, the function is called (onclick='getCoords()"). The javascript then sets that values of two hidden fields (latitude and longitude) to the GPS coords.
My issue is this: PHP is 'beating' the javascript in the sense that the field values aren't being set in time, so that each value becomes a 0. I've done a bunch of testing, and this is definitely the issue. If I do something like set a seperate button to run the javascript function, the run the form everything works fine.
Any ideas on how to solve this problem?
Gists:
https://gist.github.com/2425419
https://gist.github.com/2425394
https://gist.github.com/2425391
Along the lines of what Volkner said, block submit using a submit handler (call preventDefault), then submit at the end of itsWorking. You can either call .submit() to do the submission, or use AJAX.
I think the crux of your problem is that an <input type="image"> will submit a form just as sure as <input type="submit"> will.
However, to fix this as is, add event as a parameter to both the call and declaration of getUserLocation(event).
Then edit your JavaScript as follows:
function getUserLocation(event) {
event.preventDefault(); // prevents form from submitting
if (navigator.geolocation) {
navigator.geolocation.getCurrentPosition(itsWorking, notWorking);
}
else {
alert("Dang! Your browser doesn't support finding your location, use the zipcode method below.");
}
};
function itsWorking(position) {
var lat = position.coords.latitude;
var longi = position.coords.longitude;
var finalLat = Math.round(lat*1000000)/1000000
var finalLong = Math.round(longi*1000000)/1000000
$("#longi").val(finalLong);
$("#lati").val(finalLat);
document.getElementById('findoneform').submit(); // submits form since we were successful
};
But like I originally stated, it seems if you used an img tag instead of <input type="image">, that would prevent the form from sending in the first place (and maybe you did this on purpose, because you wanted to have two ways to submit the form?).
This issue happens because the page unloads (submits the form) before the geolocator's done doing its thing, but this way, we stop the form from submitting, and itsWorking() only gets called AFTER the geolocator has done its thing, so we don't submit the form until the end of itsWorking() when we've done everything we wanted to do.

Showing an alert() dialog box if a form does not have valid values

I have a simple form which accepts a Title and a Contents variable from a textbox and a textarea. The form will send its data to a file called add-post.php. However, I am looking for a way to alert the user that either the textbox or the textarea has invalid data (is empty) in case they click the submission button.
I was thinking that an alert() popup box would be the best idea because it doesn't redirect to any other page and the user never loses their data (imagine they entered a whole lot of text but forgot a title. Sending the data to add-post.php and performing the check there will result in loss of data for the user).
However, I'm not sure how to actually implement the alert() popup. How would I make it so that the check is done AFTER they have clicked the submit button but BEFORE the data is sent off to the next file. Any advice is appreciated.
On your form add something like this
<form name="frm1" onsubmit="InputChecker()">
Then in javascript
<script type="text/javascript">
function InputChecker()
{
if(document.getElementById({formElement}) != '') { // not empty
alert("This element needs data"); // Pop an alert
return false; // Prevent form from submitting
}
}
</script>
Also as others have said jQuery makes this a little bit easier. I highly recommend the jQuery Validate Plugin
Some people do find the alert box "annoying", so it may be better to append a message into the DOM to let the user know what needs to be fixed. This is useful if there are numerous errors as the errors will be more persistent allowing the user to see all the things they need to be fixed. Again, the jQuery Validate plugin has this functionality built in.
Attach an onsubmit event to the form, and return false; to stop the submission if checks fail.
Form validation with Javascript. Or easier with jQuery.
Basically, validate the form when the submit button is clicked (with an onsubmit handler), and then use an alert() box if needed. By the way, people usually hate alert boxes.
You have a number of options when it comes to client side validation. This is just one.
<form id="tehForm" method="post">
<input type="text" id="data2check" >
<input type="button" id="btnSubmit" />
</form>
<script type="text/javascript">
function submit_form(){
if(document.getElementById("data2check").value!="correct value"){
alert("this is wrong");
}else{
document.getElementById("tehForm").submit();
}
}
</script>
For a more indepth example check out this link

Postbacks in PHP

Is there a way to check which link/button was clicked from a form besides using
if(isset($_POST['myvar']))
{
//if true do this
}
else
{//do this}
or a querystring?
My page has a jquery drop down and thus the above isset function is not working as the form for login is contained in the dropdown.
I'm not too familiar with PHP, but going the jQuery route, you can create a hidden field
<input type="hidden" name="postSource" id="postSource" />
and then wire up some event handlers to modify that value before the page is posted.
$('#myControl1, #myControl2').change(function()
{
$('#postSource').val($(this).attr('id'))
});
.NET uses a similar technique, I think. Then on server side, you just access the posted value of the 'postSource' field.

Disabling submit button stops form from being submitted PHP / Javascript

I think I got a classic problem but I was not able to find a working solution so far.
I have got a form , the user clicks "Send" and everything works fine using a PRG pattern and doing both client-side and server-side validation.
The problem arises when any user (let's assume he entered valid inputs) clicks more then once quickly before the server script ends its execution...
I do not get any duplicated entry because I took care of that but the browser does not go to my "thanks for submitting page".
Instead it re-submits the same page with the same values and what I get are the custom errors I set to warn the user he is trying to enter details already stored in the database. The details sent in the first place are all in the database but the user has no chance to know that.
I tried to disable the submit button on a submit event using jQuery but in that case the data are not submitted.
HTML
<div id="send-button-container">
<input id="send-emails" type="submit" name="send_emails" value="Send"/>
</div>
jQuery
$(document).ready(function(){
$('#mail-form').submit(function(){
$('#send-emails').attr('disabled','disabled');
});
});
I am wondering if I can force a submission using Javascript after disabling the button and also how to deal with UAs with Javascript disabled
Thanks in advance
Depending on server-side language, the submit button being disabled could cause problems. This is because disabled elements are not POSTed to the server. Languages like ASP.NET require the button value to be submitted so it knows what event handler to fire. What I usually do is hide the submit button, and insert a disabled dummy button after it, which appears identical to the user. Then in your onsubmit handler, you can return false and submit the form programmatically...
$('#mail-form').submit(function(){
var btn = $('#send-emails');
var disBtn = $("<input type='button'/>").val(btn.val()).attr("disabled", "disabled");
btn.hide().after(disBtn);
this.submit();
return false;
});
Contradictory to the other up-voted answers, please note that you do not need to explicitly return true from your submit handler for natural form submission: http://jsfiddle.net/XcS5L/3/
I assume this means you are depending on the value of the submit button to service the request? That is you are checking
$_REQUEST['send_emails'] == 'Send';
This is not good practice. You should never depend on the value of the submit button because that is the just what is displayed to the user. Instead, you should add a hidden input that contains the event you want to fire. After the form is submitted, you don't need to care what the value of the submit button is and you can disable it. All other non-disabled data in the form is still submitted.
You can indeed force the submission after disabling the button.
$(function () {
$("#mail-form").submit(function () {
$("#send-emails").attr('disabled', 'disabled');
window.location = '?' + $("#mail-form").serialize() + '&send_mails=Send';
return false;
});
});
Server side set a $_SESSION variable that keeps track of the last time they made a submission and block submissions within a certain time.
<?php
session_start();
if (isset($_REQUEST['send_emails'])) {
if (isset($_SESSION['mail_sent'])
&& strtotime($_SESSION['mail_sent']) < strtotime('5 seconds ago')
) {
redirect_to_thanks();
}
do_post();
}
function do_post() {
if (do_validate()) {
$_SESSION['mail_sent'] = time();
redirect_to_thanks();
}
else {
yell_at_user_a_lot();
}
}
?>
You have to return true; You could try this if u want a simple button to submit the form.
$(function(){
$('#submitID').one('click',function(){
$('#formTobeSubmitted').submit();
$(this).attr('disabled','disabled');
})
});
On server side, generate a random number into each form, store the number when the form is submitted, and discard the submit if that number has already been stored earlier. When the user has disabled javascript, this is the best you can do. (Concurrency issues can be tricky as the two identical requests are handled at the same time - make sure you use some sort of locking mechanism, such as a table with a unique field or the flock() command in PHP.)
On browser side, just set a flag when the form is submitted, and discard all later submits:
$('#mail-form').submit(function() {
if ($(this).data('submitted') {
return false;
} else {
$(this).data('submitted', true).addClass('submitted');
}
});
You can use the submitted class to make the buttons gray or something. This has a few advantages to simply disabling them; Josh already said one. Another is that Firefox likes to remember disabled states when you hit refresh, which can cause your users getting stuck in certain situations.

Do browsers support autocomplete for ajax loaded login forms at all?

My problem is, that the browsers' (IE&FF) autocomplete does not work for my login form.
I have a webapp with CakePHP & jQuery. To allow visitors to login/register unobtrusively. The login form is inside a div, which is loaded via AJAX. (This enables logging in without a page reload.)
The browsers do recognize it as a login field, as they prompt me to save the credentials when clicking login. And they really do save the username/password, as they appear between the saved ones in the browser settings. But the saved username/password is never entered automatically. They do not appear pre-entered when the page loads. When I start typing in the username, the username appears as a suggestion, but even when you select it, the password is not entered next to it. Why? How can I get this working?
That you can test it yourself, here is a simple AJAX login form:
http://gablog.eu/test/ajaxlogin.html
It loads the following login form, if you go to the url below, autocomplete will work for just the plain form, so it is not a problem with the form itself, but rather that it is AJAX loaded:
http://gablog.eu/test/loginform.html
The layout:
<div id="user-bar">
<script type="text/javascript">
$(function() {
$("#user-bar").load('loginform.html').html();
});
</script>
</div>
The view loaded (when not logged in):
<form id="form-login" action="" onsubmit="login(); return false;">
<input type="text" id="username" name="username"/>
<input type="password" id="password" name="password"/>
<input type="submit" value="Login"/>
<div id="login-error" class="error-message"></div>
</form>
<script type="text/javascript">
function login() {
$.post('/ajax/login', $("#form-login").serialize(), function(data) {
if (data.success) {
$("#user-bar").load('userbar.html').html();
} else {
$("#login-error").html(data.message);
}
}, "json");
}
</script>
To clarify: I do not want to use AJAX autocomplete, I want the browser's autocomplete to work for my login form. This is an issue between my form and the browser. jQuery submission seems to play a minor role, as the usernames/passwords are saved. They are just not auto-entered for ajax loaded HTML elements! (The test site does not use jQuery submission.) Related question: browser autocomplete/saved form not work in ajax request
Autocomplete, in Firefox at least, triggers during page load. Adding the content afterwards would miss the window of opportunity.
A login form is tiny. I'd include it in the page from the outset and consider hiding it with CSS until it is wanted.
In case it helps, msdn says (towards the bottom of the page):
Note: if both of the following
conditions are true:
The page was delivered over HTTPS
The page was delivered with headers or a META tag that prevents
caching
...the Autocomplete feature is
disabled, regardless of the existence
or value of the Autocomplete
attribute. This remark applies to IE5,
IE6, IE7, and IE8.
I've emboldened the interesting bit.
.
I don't think you can get the form autocomplete to work if you load the form via ajax (security-wise I don't know if it can be really be abused or not, but the fact that a script could start loading fields into the page to see what data gets inserted doesn't look too good to me).
If you can, the best option would be to add a conditional block to the php file and include the form or not depending on whether the user is logged or not. If for some reason you can't do that, you might want to try to do a document.write() instead of the ajax call (and yes, using document.write is ugly :)
I see case when login form has to be pulled with ajax - if rest of the website loads as static html (cache). Login form (or authed user info) cant be displayed statically.
So your solution is to pull the form right after declaration (end tag) of the DOM element that serves as parent element for ajax-pulled loginform's html, ex:
<div id="loginforms_parent"></div>
<script language="javascript">
/* ajax request and insert into DOM */
</script>
And browser has the form in DOM onLoad. Tested, firefox does autocomplete in that case.
I'm not happy with loading the login form into my page at load time so I filed a issue with Chrome instead;
http://code.google.com/p/chromium/issues/detail?id=123955&thanks=123955&ts=1334713139
there is answer given : http://www.webmasterworld.com/javascript/4532397.htm . it does something with submit method and then uses click method. as i know values are not saved if form is not submitted. i think author of that solution just makes it submitted though submit button is not clicked by user.

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