if checkbox is checked change the value using PHP

Question

I'm trying to accomplish one simple task (but is not simple for me).

I have a form and I'm having a trouble with this check box.

    <input type="checkbox" name="b"  
<?php if (isset($_POST[b])) echo "value='y'"; else echo "value='n'"; ?>/>

I'm not sure if I use the right one, but it doesn't work for me.

So basically I want the value of the input of b will be y if the checkbox is checked else it will always be n if the checkbox is unchecked.

That isn't how a checkbox works. The checkbox posts a value when selected or nothing at all. Perhaps you want the radio input? — afuzzyllama
– afuzzyllama, Commented Jun 17, 2012 at 5:24
@Somebodyisintrouble yeah I forgot to put this is homework — Ali
– Ali, Commented Jun 17, 2012 at 5:47
Yes, then you would be putting the if (isset($_POST[b])) check before your insert/update query. =] — Fabrício Matté
– Fabrício Matté, Commented Jun 17, 2012 at 6:09

sachleen · Accepted Answer · 2012-06-17 05:32:40Z

4

That's not how a checkbox works.

It's checked when the checked attribute is there.

<input type="checkbox" name="a" value="a" checked /> Checked
<input type="checkbox" name="a" value="a" /> NOT Checked

So you want to use

<input type="checkbox" name="a" value="a" <?php echo isset($_POST['b']) ? "checked" : ""; ?>/>

Now if $_POST['b'] is set, the checkbox will be checked.

Also, you have $_POST[b]. The b should be in quotes. It should be $_POST['b']

answered Jun 17, 2012 at 5:32

sachleen

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2 Comments

Ali Over a year ago

well I want the value will be n if is not check and it will be y if is check` can I do the same from your code?

sachleen Over a year ago

I'm not really understanding what you're trying to do. Are you trying to get the value of the checkbox and do something with it in your code or are you trying to literally output the attribute value="y/n" to the HTML of the checkbox? If its the latter, you can add on to the echo. echo isset($_POST['b']) ? 'checked value="y"' : 'value="n"';

Ravi Kant Mishra · Accepted Answer · 2012-06-17 08:13:27Z

2

You have to use two conditions one is for showing checked/unchecked and second for showing y/n

 <input type="checkbox" name="b" <?php echo (isset($_POST['b'])?"value='y'":"value='n'")?> 
 <?php echo (isset($_POST['b'])?"checked":"") ?>  />

answered Jun 17, 2012 at 8:13

Ravi Kant Mishra

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Comments

sachleen · Accepted Answer · 2012-06-17 05:30:40Z

0

tested code!

<form method="post">
   <input type="checkbox" name="b" <?php if (isset($_POST['b'])) echo "value='y'"; else echo "value='n'"; ?>/>
   <input type="submit" name="asd" value="asd">
</form>

So go with the following

<?php if (isset($_POST['b'])) echo "value='y'"; else echo "value='n'"; ?>

edited Jun 17, 2012 at 5:30

sachleen

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answered Jun 17, 2012 at 5:27

user1461434

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1 Comment

Ali Over a year ago

Well this is the same that I'm using and it doesn't work that is why I want to know.

Justin Archiquette · Accepted Answer · 2015-04-08 03:52:11Z

0

This worked for me:
first: Giving the checkbox a default value
then: assign the desired value only if the box is checked.

    <input type="hidden" name="b" value="n">
    <input type="checkbox" name="b" value="y" >

answered Apr 8, 2015 at 3:52

Justin Archiquette

1

Comments

Zetty 0905 · Accepted Answer · 2018-01-25 04:24:32Z

0

*Approved by Deployment:

        <input type="radio" name="dep_approval_status" value="Approved"
            <?php 
                if ($deploy['dep_approval_status'] === "Approved")
                {
                    echo ' checked'; 
                }

            ?> 
        /> Yes, approved 

        <input type="radio" name="dep_approval_status" value="Not Approved"
            <?php 
                if ($deploy['dep_approval_status'] === "Not Approved")
                {
                    echo ' checked';
                }
            ?> 
        /> Not Approved

answered Jan 25, 2018 at 4:24

Zetty 0905

1

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