Change value by JavaScript - php

Question

The value of the button should change in 1 or 0, but the echo $_POST["ordina"] give always 1 and I don't understand because the code seems correct.
<script> function order() {
if (document.ordination.ordina.value == "1") {
document.ordination.ordina.value = "0";
} else {
document.ordination.ordina.value = "1";
} }</script>
<?php echo $_POST["ordina"]; ?>
<form id="ordination" name="ordination" method="POST" action="">
<button type="submit" value="1" class="button" name="ordina" onclick="order();return true;">Ordina</button>
The alert(document.ordination.ordina.value) give always 1.
Some can help me?

Answer 1

Check it now..
<script> function order() {
if (document.ordination.ordina.value == "1") {
alert(document.ordination.ordina.value); // this one shows 1
document.ordination.ordina.value = "0";
} else {
alert(document.ordination.ordina.value); // this one shows 0
document.ordination.ordina.value = "1";
} }</script>
<?php echo $_POST['ordina'];?>
<form id="ordination" name="ordination" method="POST" action="">
<button type="submit" value="<?php if(isset($_POST['ordina'])){echo $_POST['ordina'];}else{ echo '1';}?>" class="button" name="ordina" id="ordina" onclick="order();return true;">Ordina</button>
after you submit this form the <?php echo $_POST['ordina'];?> is 0...
and set to button value as 0 and again submit the value can be changed to 1.
and its consequently changed 0 to 1 to 0 to 1 but you have first time load this page means the alert shows 1 only..

Answer 2

This always return 1, because your button is a "submit" button, so the body is reloaded each time you click on the button.
<script>
function order() {
if (document.ordination.ordina.value == "1") {
document.ordination.ordina.value = "0";
} else {
document.ordination.ordina.value = "1";
}
alert(document.ordination.ordina.value);
}
</script>
<form id="ordination" name="ordination" method="POST" action="">
<button type="button" value="1" class="button" name="ordina" id="ordina" onclick="order();return true;">Ordina</button>
</form>
I change type "submit" for "button", then it works.

Answer 3

<script> function order() {
if ($("#ordina").val() == "1") {
$("#ordina").val(0);
} else {
$("#ordina").val(1);
} }</script>
<?php echo $_POST["ordina"]; ?>
<form id="ordination" name="ordination" method="POST" action="">
<button type="submit" value="1" class="button" name="ordina" id="ordina" onclick="order();return true;">Ordina</button>