How can I detect which submit button was pressed?

Question

I have a script in PHP where I need to detect which button was pressed in a HTML page. I have found lots of similar questions asked by other people, but I am having problems.

HTML

<form method="post" action="kode/kode_newsletter_operation.php" id="newsletter_step3Form">
                    <p>
                        <label>Schedule newsletter:</label>
                        <select name="send_date_month" id="send_date_month">
                            <option value="01">January</option>
                            <option value="02">February</option>
                            <option value="03">March</option>
                            <option value="04">April</option>
                            <option value="05">May</option>
                            <option value="06">June</option>
                            <option value="07">July</option>
                            <option value="08">August</option>
                            <option value="09">September</option>
                            <option value="10">October</option>
                            <option value="11">November</option>
                            <option value="12">December</option>
                        </select>
                        -
                        <select name="send_date_day" id="send_date_day">
                            <option value="01">1</option>
                            <option value="02">2</option>
                            <option value="03">3</option>
                            <option value="04">4</option>
                            <option value="05">5</option>
                            <option value="06">6</option>
                            <option value="07">7</option>
                            <option value="08">8</option>
                            <option value="09">9</option>
                            <option value="10">10</option>
                            <option value="11">11</option>
                            <option value="12">12</option>
                            <option value="13">13</option>
                            <option value="14">14</option>
                            <option value="15">15</option>
                            <option value="16">16</option>
                            <option value="17">17</option>
                            <option value="18">18</option>
                            <option value="19">19</option>
                            <option value="20">20</option>
                            <option value="21">21</option>
                            <option value="22">22</option>
                            <option value="23">23</option>
                            <option value="24">24</option>
                            <option value="25">25</option>
                            <option value="26">26</option>
                            <option value="27">27</option>
                            <option value="28">28</option>
                            <option value="29">29</option>
                            <option value="30">30</option>
                            <option value="31">31</option>
                        </select>
                        -
                        <select name="send_date_year" id="send_date_year">
                            <option value='2012'>2012</option><option value='2013'>2013</option>                                </select>&nbsp;
                            <select name="send_date_hour" id="send_date_hour">
                                <option value="00">0</option>
                                <option value="01">1</option>
                                <option value="02">2</option>
                                <option value="03">3</option>
                                <option value="04">4</option>
                                <option value="05">5</option>
                                <option value="06">6</option>
                                <option value="07">7</option>
                                <option value="08">8</option>
                                <option value="09">9</option>
                                <option value="10">10</option>
                                <option value="11">11</option>
                                <option value="12">12</option>
                                <option value="13">13</option>
                                <option value="14">14</option>
                                <option value="15">15</option>
                                <option value="16">16</option>
                                <option value="17">17</option>
                                <option value="18">18</option>
                                <option value="19">19</option>
                                <option value="20">20</option>
                                <option value="21">21</option>
                                <option value="22">22</option>
                                <option value="23">23</option>
                            </select>:<select name="send_date_min" id="send_date_min">
                                <option value="00">00</option>
                                <option value="00">05</option>
                                <option value="10">10</option>
                                <option value="00">15</option>
                                <option value="20">20</option>
                                <option value="00">25</option>
                                <option value="30">30</option>
                                <option value="00">35</option>
                                <option value="40">40</option>
                                <option value="00">45</option>
                                <option value="50">50</option>
                                <option value="00">55</option>
                            </select>
                            <div>Server Time: October 12, 2012 04:54</div>
                        </p>
                        <p>
                            <label for="send_date">Preview in Email:</label>
                            <input type="text" id="preview_email"  value="" name="preview_email" />
                            <input type="button" id="preview_btn" name="preview_btn" class="btn btn_red" onclick="previewSendMail(1)" value="Send Preview"/>
                        </p>
                        <p>&nbsp; </p>
                        <div id="kode_result"></div>
                        <div id="content_buttons">
                            <input type="button" class="btn btn_blue big" name="goback" value="Last Step" onclick="window.location.href='./newsletter_create_step2.php?id=1'" />
                            <input type="submit" name="submit_btn_now" value="Send now!" class=" btn btn_red big"/>
                            <input type="submit" name="submit_btn" value="Schedule" class=" btn btn_green big"/>
                            <input name="action" type="hidden" value="newsletter_step3" />
                            <input type="hidden" name="newsletter_id" id="newsletter_id" value="1"/>
                        </div>
                    </form>

PHP

print_r($_POST);

Output

Array(
[send_date_month] => 10
[send_date_day] => 12
[send_date_year] => 2012
[send_date_hour] => 01
[send_date_min] => 50
[preview_email] =>
[action] => newsletter_step3
[newsletter_id] => 1
)

Both buttons are inside the <form> tag but the $_POST array doesn't include any info about them. What am I doing wrong? Do the most recent browsers send no information about the submit button or am I missing something? I have no skills in javascript to develop a workaround for this, I only know PHP.

Thanks in advance.

Two separate forms are not needed. I've used two submit buttons in a single form hundreds of times. — maiorano84
– maiorano84, Commented Oct 11, 2012 at 23:21
I've tried your code in my development environment and sorry to say but [submit_btn_now] or [submit_btn] return as expected in the $_POST array. What is your web server software and PHP version? scuzzy.id.au/stackoverflow/12850041.php — Scuzzy
– Scuzzy, Commented Oct 11, 2012 at 23:34
You can use firebug with firefox to review the post data sent in the request, I'd suggest looking at what the client is submitting. (Network tab, with "persist" enabled) — Scuzzy
– Scuzzy, Commented Oct 11, 2012 at 23:43
No he's right, try loading JQuery on your page and using some of the validation features. It captures the event, returns default, then submits it itself. — user1726343
– user1726343, Commented Oct 11, 2012 at 23:47

Scuzzy · Accepted Answer · 2012-10-11 23:30:23Z

8

Give the submit buttons the same name attribute, but with different values, then you can test against the text that is used on the submit button.

<pre><? print_r($_POST);?></pre>
<form method="post">
<input type="submit" name="button" value="AAA">
<input type="submit" name="button" value="BBB">
</form>

Ouput:

Array
(
    [button] => AAA
)

Edit: Actually, I see nothing wrong with your code?

<pre><? print_r($_POST);?></pre>
<form method="post">
<input type="submit" name="submit_btn_now" value="Send now!" class=" btn btn_red big"/>
<input type="submit" name="submit_btn" value="Schedule" class=" btn btn_green big"/>
</form>

Output only clicking one:

Array
(
    [submit_btn_now] => Send now!
)

edited Oct 11, 2012 at 23:30

answered Oct 11, 2012 at 23:22

Scuzzy

12.4k2 gold badges50 silver badges48 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Scuzzy Over a year ago

Actually, I put the code by @gtugablue into my test (obviously without knowing his <form> element) and honestly it worked as you'd expect, there must be some other underlying issue here.

user1726343 Over a year ago

what I'm thinking is he has nothing but the buttons, like your example, and GET as the method, which gives him an empty POST.

Scuzzy Over a year ago

I'd assume this as well, you should post an answer about the method attribute of a form element and I'll upvote it.

score 3 · Accepted Answer · 2012-10-12 00:02:39Z

3

Do you have JQuery or any other JS libraries running on your form? They tend to take over the submit event and thus the submit doesn't come from the actual submit input. Try it without a js library?

EDIT: Here is a work around:

$('#submit_btn_now').on('click', function() {
    var hiddensubmit=document.createElement('input');
    hiddensubmit.value = this.value;
    hiddensubmit.name = this.name;
    hiddensubmit.setAttribute('hidden','hidden');
    $('#newsletter_step3Form').append(hiddensubmit);
    $('#newsletter_step3Form').submit()
    return false;
});

edited Oct 12, 2012 at 0:02

answered Oct 11, 2012 at 23:38

user1726343

4 Comments

Scuzzy Over a year ago

I rather like this (just add an attribute type of hidden)

Scuzzy Over a year ago

Actually, what if there is a "return false" as part of a validation routine that prevents the submit, maybe you should "clean up" dynamically added fields before creating new ones.

user1726343 Over a year ago

well it's a full fledged submit, so you won't see it, really, but alright. I'm not sure I see what you mean by cleaning up dynamically added fields, but yes if a handler is already passing false we have a problem.

gtugablue Over a year ago

Yes, that was exactly the problem. I had a headhache looking at the PHP and HTML scripts without detecting the problem but I didn't notice there was a javascript file taking over the submit event. Thanks for the replies.

Hoffmann · Accepted Answer · 2014-04-08 10:53:14Z

1

If you want to use the same value for all buttons (as it is the value that is shown as text) you could use the name attribute as information holder and prefix it. The way to get the value is then:

$information = substr(
  end(
    array_filter(
      array_keys($_REQUEST),
      function ($key) { return substr($key, 0, strlen(PREFIX)) == PREFIX; }
    )
  ),
  strlen(PREFIX)
);

answered Apr 8, 2014 at 10:53

Hoffmann

1,0829 silver badges28 bronze badges

Comments

bloodymurderlive · Accepted Answer · 2015-06-18 20:14:35Z

0

Set both buttons' name attribute to the same value.
Give each button a different value attribute, like so:

<input type="submit" name="submit" value="Log In">
<input type="submit" name="submit" value="Sign Up">

Then you can use an if statement in your php, like so:

if ($_POST['submit']=="Log In") {}
else {} // ELSE DETECTS THE "Sign Up" BUTTON, OR ANY OTHER BUTTON WITH A DIFFERENT VALUE

I think this pretty much gives you exactly the answer you were looking for: A way to detect which button was pressed using just PHP and no JavaScript.

answered Jun 18, 2015 at 20:14

bloodymurderlive

3874 silver badges15 bronze badges

Collectives™ on Stack Overflow

How can I detect which submit button was pressed?

4 Answers 4

3 Comments

4 Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

3 Comments

4 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related