PHP, Buttons & Variables

[gaucho]

Hello all,

have a little problem getting some buttons to work.
OK, I have a form, with some submit-buttons that dynamically reproduce some input fields, I had a hard time getting them to work the way I wanted, no they do.
My problem is now, that the caption on the button is not the one I want them to have, because the "value" is now the variable I need to identify it in the catch-routine after submit, and this is only numbers.
OK, I know this sounds a little weird, so let me give you a little of the code to clarify the problem:

as it was:
<form>
.....
some fields
.......

for( $i = 0; $i <= $a; $i++){

echo "<table id ='group[" . $i . "]' name='group[" . $i . "]' border='1' cellspacing='0' cellpadding='1'>
<tbody>
<td>Name:</td>
<td><input type='text' id=name[" . $i . "]' name=name[" . $i . "]' value=\"" . $name[$i] . "\" ></td>
</tr>
.......
some more fields
.......
<tr>
<td>
<input type='submit' id=name='plus_btn' name='plus_btn' value = ' + ' >
</td>
</tr>
</table>
</form>

OK, the problem with this one is that if you have say 5 of these tables, and you pressed the the +-buton of the third table, no matter what, the sender does not get identified after reload. To solve the problem I played with the name, etc. Finally I found out that there is no other way than changing the button code to look like this:

<input type='submit' id=name='plus_btn' name='plus_btn' value =".$i" >

This way the catch routine could identify the button the submit came from. This looks like this:

if( isset( $POST['plus_btn'] ) ){
$temp = $POST['plus_btn']; //this returns the integer identifying the button

DO SOMETHING WITH $temp;

}

This is the functionality I wanted so far. But the caption of the buttons is the integer value of $i now. A user can't see what the button is used for. No problem, I said, use a GIF to hide it:

<input type='submit' src='plus.gif' id=name='plus_btn' name='plus_btn' value =".$i" >

This doesn't work, the image doesn't show up, so I changed it to type "image", now the catch-routine doesn't Identify the button any more, because the value is ignored, so I looked around again and cahnged it to look like this:

<button type='submit' id='plus_btn' name='plus_btn' value=".$i."><img src='plus.gif'></button>

Now the catch routine returns "<img src='plus.gif'>", which is not desired.

Can anybody tell me how to get the "+" shown on the button, but getting the integer value of $i returned?
No matter if the "+" comes from a picture or is just the letter.

Would appreciate any help.
Thanks in advance

gaucho

[GBahle]

Hm, without knowing the exact look of the form, i would give the button the desired value (that is, "+" e.g.), then add a hidden field to the form which has the actual value ($i) <input type="hidden" name="plus_btn_value" value="<?php echo $i; ?>">
that way you can still check the isset of the button; all you have to do is retrieve the actual value from the hidden field.

[gaucho]

Originally posted by GBahle
Hm, without knowing the exact look of the form, i would give the button the desired value (that is, "+" e.g.), then add a hidden field to the form which has the actual value ($i) <input type="hidden" name="plus_btn_value" value="<?php echo $i; ?>">
that way you can still check the isset of the button; all you have to do is retrieve the actual value from the hidden field.

Hi GBahle,

OK, the way you proposed it somehow works, but not with the desired effect. It just attaches another part-form at the end. The way I wrote the code, it is also possible to insert a dataset somewhere within.

But thanks for your response.

Any other ideas?

Best regards

gaucho

[GBahle]

Actually, I'm confused by your reply.

What I had in mind was:

Add a corresponding hidden field for any button you want to associate with a value. Then, in your catch routine, do

if( isset( $POST['plus_btn'] ) ){
$temp = $POST['plus_btn_value']; //this returns the integer which FORMERLY identified the button and is now stored in the hidden field

DO SOMETHING WITH $temp;

}

As far as i see it, that shouldn't modify your code in the slightest, expect for adding some line and thus should work exactly the same as your previous solution.

Please clarify if it doesn't.

[gaucho]

Sorry that I reply that late, but my bios-chip exploded this weekend, don't know how this could happen.

Well, this is something different, I'll try this right away tomorrow morning and I'll tell you what came out.

Thanx again

Gaucho

[gaucho]

Hello Gbahle,
I think I did what you proposed, but it doesn't work, but just in case, take a look at the code and see if I did it the correct way.

<?

if ( !empty( $POST ) ) {
extract( $POST );
}

.......
some other code
.............

if ( isset( $_POST['plus_btn'] ) ) {

$new_contact = $_POST['plus_btn_value'];
if ($new_contact < $a ) {
for ($k = $a; $k >= $new_contact; $k--){
	$kd_name[$k+1] = $kd_name[$k];
	$kd_firstname[$k+1] = $kd_firstname[$k];

	if ($k == $new_contact) {
	$kd_name[$k+1] = "";
	$kd_firstname[$k+1] = "";
	}
				}
	}

$a++;		
$i = 0;
$_POST['a'] = $a;

}

if ( isset( $POST['minus_btn'] ) ) {
$del_con = $POST['minus_btn_value'];

if ( $del_con < $a ) {
for ($m = $del_con; $m < $a; $m++){
	$kd_name[$m] = $kd_name[$m+1];
	$kd_firstname[$m] = $kd_firstname[$m+1];

				}

		}

$a--;
$i = 0;
$_POST['a'] = $a;

}
[/COLOR]
?>

After this there is a regular HTML-form, followed by two buttons to add the first part-form, or to get rid of all of them.

<HTML>
<BODY>
<FORM>
<TABLE>
some input fields go here
</TABLE>
<?php
echo "<div>Contacts: </div><input type='text' name='kd_contacts_yn' value='".$POST['kd contacts_yn']."' size='5' readonly >

<input type='submit' name='contacts_yes_btn' value='YES'>

<input type='submit' name='contacts_no_btn' value='NO'><br>";

if ( $POST['kd_contacts_yn'] == "YES" ) {
$a = $POST['a'];
for( $i = 0; $i <= $a; $i++) {

echo "<table id ='contact[".$i."]' name='contact[".$i."]' border='1' cellspacing='0' cellpadding='1'>
<tbody>
<tr><td colspan='2' align='center'> " . ( $i + 1 ) . ". Contact </td></tr>
<tr>
<td width='25%'>Name:</td>
<td><input type='text' id='kd_name[".$i."]' name='kd_name[".$i."]' value='".$kd_name[$i]."' ></td>
</tr>
<tr>
<td>First name:</td>
<td><input type='text' id='kd_firstname[".$i."]' name='kd_firstname[".$i."]' value='".$kd_firstname[$i]."' ></td>
</tr>
<tr>
<td align='right' colspan='2'><input type='hidden' id='plus_btn_value' name='plus_btn_value' value=".$i."><input type='hidden' id='minus_btn_value' name='minus_btn_value' value=".$i." ><input type='submit' id='plus_btn' name='plus_btn' value=' + ' > <input type='submit' id=name='minus_btn' name='minus_btn' value =' - ' > <input type='hidden' id='a' name='a' value=".$a." >

</tr>
</tbody>
</table>";

	}
} [/COLOR]

?>

After this there is a button that calls some code to save the data to the database.

</FORM>
<BODY>
<HTML>

I tried to put the hidden fields behind each button, at the beginning of the part-form and the way they are now, but like I said, it didn't work. What I wanted only works the way I described before.

Hope you or somebody else can help.

Best regards

Gaucho

[GBahle]

In this example, the technique works just fine. Save both as files and name the first one any way you want, the second one test2.php

<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>

<body>
<form name="testForm" method="post" action="test2.php">
  <input type="submit" name="minus_btn" value="&nbsp;-&nbsp;">
  <input type="hidden" name="minus_btn_value" value=2>
  <input type="submit" name="plus_btn" value="&nbsp;+&nbsp;">
  <input type="hidden" name="plus_btn_value" value=1>
  <input type="submit" name="other" value="other">
</form>
</body>
</html>

<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>

<body>
<?php

if (isset($_POST["minus_btn"])) {
	print "Minus button has been hit. Its value is ".$_POST["minus_btn_value"];
} else if (isset($_POST["plus_btn"])) {
	print "Plus button has been hit. Its value is ".$_POST["plus_btn_value"];
} else {
	print "No known button.";
}

?>
</body>
</html>

[gaucho]

Hi again,
I see, well, how you did it, the values are statically defined, and this works, even if you call the same site, but keeping your example, which I modified a little to match my needs and functionality, this doesn't work any more.
Just copy the code below and save the file as test3.php, try it, and you'll see what I mean.

<?php
if (isset($_POST)) {
    extract($_POST);
}

if (isset($_POST["minus_btn"])) {
    print "Minus button has been hit. Its value is ".$_POST["i"];
}
elseif (isset($_POST["plus_btn"])) {
    print "Plus button has been hit. Its value is ".$_POST["i"];
} else {
    print "No or no known button pressed.";
}

if (isset($_POST['reset_form'])) {
    unset($_POST);
}


echo "<html>
<head>
<title>Untitled Document</title>
<meta http-equiv='Content-Type' content='text/html; charset=iso-8859-1'>
</head>

<body>
<form name='testForm' method='post' action='test3.php'>
How many button-groups shall I create? <input type='text' name='fields' value='".$_POST['fields']."' size='2'>
<input type='submit' name='create_btn' value='create button-groups'><br>";
if(isset($_POST['create_btn']) || $_POST['fields'] > 0){
for ($_POST['i'] = 1; $_POST['i'] <= $_POST['fields'];$_POST['i']++){

echo  "Buttongroup ".$i." :   <input type='submit' name='minus_btn' value='&nbsp;-&nbsp;'>
  <input type='hidden' name='minus_btn_value' value='".$_POST['i']."'>
  <input type='submit' name='plus_btn' value='&nbsp;+&nbsp;'>
  <input type='hidden' name='plus_btn_value' value='".$_POST['i']."'><hr>";
} 
} 

echo "
<input type='submit' name='reset_form' value='reset form'>
</form>
</body>
</html>";

?>

Now, if you replace the + by $POST['i']
<input type='submit' name='plus_btn' value='&nbsp;+&nbsp;'>
=>
<input type='submit' name='plus_btn' value='".$POST['i']."'>
the same with the -,
you'll see that it'll work.

Thanx again

[GBahle]

Your script doesn't run on my machine (first of, $_POST["fields"] is initially not set and when i submit, it creates a cgi error). Anyway, at least i understand what you are trying to do now.
Here's a revised script: (again, pages test1.php test2.php)

<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>

<body>
<form name="testForm" method="post" action="test2.php">
<?php
for ($i = 0; $i < 3; $i++) {
echo"
  <input type=\"submit\" name=\"minus_btn_$i\" value=\"&nbsp;-&nbsp;\">
  <input type=\"hidden\" name=\"minus_btn_value_$i\" value=$i>
  <input type=\"submit\" name=\"plus_btn_$i\" value=\"&nbsp;+&nbsp;\">
  <input type=\"hidden\" name=\"plus_btn_value_$i\" value=\"$i\"><br><br>
";
}
?>
</form>
</body>
</html>

<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>

<body>
<?php

for ($i = 0; $i < 3; $i++) {
	if (isset($_POST["minus_btn_$i"])) {
		print "Minus button ($i) has been hit. Its value is ".$_POST["minus_btn_value_$i"];
	} else if (isset($_POST["plus_btn_$i"])) {
		print "Plus button ($i) has been hit. Its value is ".$_POST["plus_btn_value_$i"];
	}
}
?>
</body>
</html>

Of course, in this example, you can just as well forget about the hidden field, since the values of the buttons are equal to the loop index variable.
On the other hand, you could use the index to assign value based on an array on its own (meaning instead of value=$i you had value=$predefinedValues[$i]) which would make the hidden fields neccessary. On the other hand, you could use sessions to accomplish the same by handing over $predefinedValues to the second page.

Let me know if that's still not what you need 🙂

[gaucho]

Hello again,
YES, YES, you saved my life, thank you much.
What you proposed really works, I did replace my variables with the ones I proposed, and after the first successful test I even deleted the hidden input fields, and it works.
But let me ask a final question, I just don't understand where the cgi-error comes from. Exactly this way it runs on my machine without problem. Hope this is not a dumb question.
OK, I know too that normally this is bad coding, I mean not to initialize a variable, in C++ one has to do it too in order not to get an error. Well, I would get a notice, at least if I would not have disabled E_NOTICE in Apache error handling, but php didn't have any problems with uninitialized variables, at least till this version. Well I didn't encounter any yet.
OK, maybe by addidng $_POST['fields'] = 0; to my first lines in the script should remove your problem, or did you already try?

What I mean is this:

if(!empty($_POST)){
extract($_POST);
}
else{
$_POST['fields'] = 0; //initialize the variable (-s) here.
}

Should work, at least in this case, I hope.

Thanks again.

Best regards

Gaucho

[GBahle]

Nope, i fixed that. The cgi error is probably a glitch of my server, it did that once before.
Doesn't really matter if your script works the way you want it to now 🙂