I put a variable (price) to a html form from database.
then user changes the price and submit the form and variable is updated in database.
I want to keep previous value (last state and show it in the form) but if I update the form variable keeps updating.
What is best way to remember previous value of variable (in array for example) ?
If you're updating this data in an actual Database, you should create a parallel table that holds the value of the previous row.
Otherwise, if you're updating only an array, you can just create a copy prior to updating the array: http://codepad.org/SvlasJ7f
<?php
$array = array('Old Value');
$lastarray = '';
updateArray($array,'New Value');
function updateArray(&$a,$v) {
$GLOBALS[lastarray] = $a;
$a = array($v);
}
?>
If you want to retain the LAST value AND display it on the screen, combine the two! Just display the previous value, in a readonly input field in your form. That way, you will still have the previous value every time the form is submitted.
<form action="process.php" method="POST">
<input type="text" name="Current" value="...">
<input type="text" name="Last" value="..." readonly="readonly">
</form>
Or am I missing something?
Related
Please see this link
http://thedesigningworld.com/bea
Here's a Small form contains 8-9 fields + a group of checkboxes
I want to save all details in DB + want to display in a table in proper manner, but it not works properly
Here's the code which i used
for($i=0;$i<count($_POST[wert1]);$i++)
{
if($_POST[wert1][$i]!= "")
{
$check1[] =$_POST['wert1'][$i]; } }
$new1=implode(',', $check1);
$result = "INSERT into table1(check1) values($new1)";
$result = mysqli_query($con, $result);
So i've one doubt that for each checkbox row, should i need to define same array name or different like here i used array name as wert1[] for first row
Checkbox values are not transmitted if the box is not checked.
If you have influence, you could put a hidden input field of the same name before the checkbox and the value "0", like:
<input type="hidden" name="checkbox_name" value="0" />
<input type="checkbox" name="checkbox_name" value="1">Some Text</input>
In you example site, you're using array notation, which is basically a good thing. However, you have not given an index so you might not recognize missing elements.
For a shopping cart application I'm working on for a class, I have to display information across every step. My problem is that I can display information only from the previous step. For step 1, an item is selected from a radio box. It is then stored like so:
function processStep1() {
//Implemented sessions
$_SESSION["items"] = $_POST["items"];
displayStep2();
}
Step 2 asks for a quantity and then validates it, like so:
function processStep2() {
//Implemented sessions
$_SESSION["quantity"] = $_POST["quantity"];
if ( preg_match('/^\d+$/',$_POST["quantity"]) ) {
displayStep3();
} else {
echo "ERROR: Quantity entered was invalid. Please try again.";
displayStep1();
}
}
(As an aside, I can't seem to get this to just refresh the current step (which would be displayStep2) when the input is not an integer, as I get an error every time I try to do so. If anyone has an answer for why that is, that is additionally helpful.)
But then on Step 3 of the form, I try to run the following line:
<p>You have selected <?php echo $_POST["quantity"] ?> units of the <?php echo $_POST["items"] ?>.<p>
Which responds with an error every time. I have tried various configurations of this same output, and have determined that it will always parse $_POST["quantity"], but never $_POST["items"]. I need it to do both.
Your third form does not "see" $_POST['items'] because it was not submitted to that form. You stored it in a session instead. Start a new session on your third form and request $_SESSION['items'].
Step 1
<form name="step1" method="post" action="whateverPageContaintsProcessStep1.php">
<input type="radio" name="items" value="item1">Item 1
<input type="radio" name="items" value="item2">Item 2
</form>
When we submit our form the $_POST data that is going to be send will be the value of the radio button we selected we selected.
Step 2
<form name="step2" method="post" action="whateverPageContaintsProcessStep2.php">
<input type="number" name="quantity" value="0" />
</form>
When we submit form2 the $_POST data will contain the value of the textbox called quantity, however since this form does not contain the previous radio buttons this value will not be send to the server and therefor we will not be able to access it in 'whateverPageContaintsProcessStep2.php'.
This is more of a technique question rather than maybe code. I am having a php form with many fields (items to select). Naturally some of the items might be selected and some not. How do I know which ones are selected when i post the data from page 1 to page 2? I thought of testing each one if empty or not, but there are just too many fields and it doesn't feel at all efficient to use or code.
Thanks,
UPDATE EDIT:
I've tried the following and maybe it will get me somewhere before I carry on testing the repliers solutions...
<html>
<body>
<form name="test" id="name" action="testprocess.php" method="POST">
<input type="text" name="choices[shirt]">
<input type="text" name="choices[pants]">
<input type="text" name="choices[tie]">
<input type="text" name="choices[socks]">
<input type="submit" value="submit data" />
</form>
</body>
</html>
and then second page:
<?php
$names = $_POST['choices'];
echo "Names are: <br>";
print_r($names);
?>
This gives out the following:
Names are: Array ( [shirt] => sdjalskdjlk [pants] => lkjlkjlk [tie]
=> jlk [socks] => lkjlkjl )
Now what I am going to try to do is iterate over the array, and since the values in my case are numbers, I will just check which of the fields are > 0 given the default is 0. I hope this works...if not then I will let you know :)
I think what you're looking for is this:
<form action="submit.php" method="POST">
<input type="checkbox" name="checkboxes[]" value="this" /> This
<input type="checkbox" name="checkboxes[]" value="might" /> might
<input type="checkbox" name="checkboxes[]" value="work" /> work
<input type="submit" />
</form>
And then in submit.php, you simply write:
<?php
foreach($_POST['checkboxes'] as $value) {
echo "{$value} was checked!";
}
?>
The square brackets in the name of the checkbox elements tell PHP to put all elements with this name into the same array, in this case $_POST['checkboxes'], though you could call the checkboxes anything you like, of course.
You should post your code so we would better understand what you want to do.
But from what I understood you are making a form with check boxes. If you want to see if the check boxes are selected, you can go like this:
if(!$_POST['checkbox1'] && !$_POST['checkbox2'] && !$_POST['checkbox3'])
This looks if all the three check boxes are empty.
Just an idea:
Create a hidden input field within your form with no value. Whenever any of the forms fields is filled/selected, you add the name attribute of that field in this hidden field (Field names are saved with a comma separator).
On doing a POST, you can read this variable and only those fields present in this have been selected/filled in the form.
Hope this helps.
Try this.....
<?php
function checkvalue($val) {
if($val != "") return true;
else return false;
}
if(isset($_POST['submit'])) {
$values = array_filter(($_POST), "checkvalue");
$set_values = array_keys($values);
}
?>
In this manner you can get all the values that has been set in an array..
I'm not exactly sure to understand your intention. I assume that you have multiple form fields you'd like to part into different Web pages (e.g. a typical survey form).
If this is the case use sessions to store the different data of your forms until the "final submit button" (e.g. on the last page) has been pressed.
How do I know which ones are selected when i post the data from page 1 to page 2?
is a different question from how to avoid a large POST to PHP.
Assuming this is a table of data...
Just update everything regardless (if you've got the primary / unique keys set correctly)
Use Ajax to update individual rows as they are changed at the front end
Use Javascript to set a flag within each row when the data in that row is modified
Or store a representation of the existing data for each row as a hidden field for the row, on submission e.g.
print "<form....><table>\n";
foreach ($row as $id=>$r) {
print "<tr><td><input type='hidden' name='prev[$id]' value='"
. md5(serialize($r)) . "'>...
}
...at the receiving end...
foreach ($_POST['prev'] as $id=>$prev) {
$sent_back=array( /* the field values in the row */ );
if (md5(serialize($sent_back)) != $prev) {
// data has changed
update_record($id, $sent_back);
}
}
I have a form when the user types something in, it will appear on the screen. I kept the text that the user typed in a variable called $output, then I tried to put each $output into an array called $arrayText, my objective is to have the user type in something and click a button, then the user's text appears on the screen and when he tries for the second time, the first text is still there while the new one will be on the next line. However, it works only for the first time. For the second time, it replaces the second text with the old one, here is my code
if (isset($_POST['putContents'])) {
$output = $_POST['contents'];
test();
}
function test()
{
static $arrayText = array();
global $output;
$arrayText[]= $output;
for($i = 0; $i < count($arrayText); $i++){
echo $arrayText[$i];
echo "<br>";
}
}
}
?>
thanks for any help in advance
You can't "collect" the user input line-by-line into an array after each time he presses the submit button. The lines must be persisted (stored) somewhere. You can store each line as a record in a database or in a session cookie as suggested. I would persist the state by storing the entered lines in hidden input tags inside your form:
<input type="hidden" name="line[0]" value="What the user typed in first" />
<input type="hidden" name="line[1]" value="The second line that was typed in" />
<input type="text" name="contents" value="" />
By executing a second time your script your $_POST will only have the values of your last submit which in your case will override your array.
If you want to store data beyond the current process you'll have to store the date somewhere other then the $_POST global.
I'm suggesting you use sessions for this as a database query would certainly over blow your needs.
Use:
session_name("admin");
session_start();
if(empty($_SESSION["yourOldText"])) $_SESSION["yourOldText"]=$_POST["userinput"];
and if you want to access your old data then you can just use $_SESSION["yourOldText"]
I've just started using jQuery. One thing I've been using it for is adding rows to a table that is part of a form.
When I add a new row, I give all the form elements names like 'name_' + rowNumber. I increment rowNumber each time I add a row.
I also usually have a Remove Row Button. Even when a row is removed, the rowNumber count stays the same to keep from repeating element names.
When the form is submitted, I set a hidden element to equal the rowNumber value from jQuery. Then in PHP, I count from 1 to the rowNumber value. Then for each value, I perform an isset($_REQUEST['name'_ . index]). This is how I extract the form elements that remained after deleting rows in jQuery.
Does anyone here have a better technique for accounting for deleted rows?
For some of our simpler tables, we use a field name such as 'name[]', though for JavaScript they would need a usable id.
It does add some complexity in that 'name[0]' has to assume 'detail[0]' is the correct element.
PHP will create an array and append elements if the field name ends with [] similar to
<input name="field[]" value="first value" />
<input name="field[]" value="second value" />
// is roughly the same as
$_POST['field'][] = 'first value';
$_POST['field'][] = 'second value';
Use arrays to hold you values in your submission. So bin the row count at the client side, and name your new elements like name[]. This means that $_POST['name'] will be an array.
That way at the server side you can easily get the row count (if you need it) with:
$rowcount = count($_POST['name']);
...and you can loop through the rows at the server side like this:
for ($i = 0; isset($_POST['name'][$i]; $i++) {}
You could extract all the rows by doing a foreach($_POST as $key => $value).
When adding a dynamic form element use the array naming method. for example
<input type="text" name="textfield[]" />
When the form is posted the textfield[] will be a PHP array, you can use it easily then.
When you remove an element make sure its removed from the HTML DOM.
Like blejzz suggests, I think if you use $_GET, then you can just cycle through all of the inputs that were sent, ignoring the deleted rows.
foreach ($_GET as $k=>$v) {
echo "KEY: ".$k."; VALUE: ".$v."<BR>";
}
I notice that you mention "accounting for deleted rows"; you could include a hidden input, and add a unique value to it each time someone deletes a row. For example, the input could hold comma-separated values of the row numbers:
<input type="hidden" value="3,5,8" id="deletions" />
and include in your jQuery script:
$('.delete').click(function(){
var num = //whatever your method for getting the row number
var v = $('#deletions').val();
v = v.split(',');
v.push(num);
v = v.join(',');
$('#deletions').val(v);
});
Then you should be able to know which rows were deleted (if that is what you were looking for).
you can use POST or GET
After submit you can use all of your form element with this automaticly. You dont need to reorganise your form element names. Even you dont need to know form elements names.
<form method="POST" id="fr" name="fr">.....</form>
<?php
if(isset($_POST['fr'])){
foreach($_POST as $data){
echo $data;
}
}
?>
Also you should look this
grafanimasyon.blogspot.com.tr/2015/02/veritabanndan-php-form-olusturucu.html
This is a automated form creator calcutating your database tables. You can see how to give name to form elements and use them.