Php 如何在javascript表单上保存数据

Php 如何在javascript表单上保存数据,php,javascript,forms,Php,Javascript,Forms,我在JS上有两个功能: <script> function inc(elem) { elem.value++; } function dec(elem) { if(elem.value>1) { elem.value--; } } </script> 功能公司(elem) { 元素值++; } 函数dec(elem) { 如果

我在JS上有两个功能:

<script>
    function inc(elem)
    {
        elem.value++; 
    }
    function dec(elem)
    {
        if(elem.value>1)
        {
            elem.value--;
        }
    }
</script>

功能公司(elem)
{
元素值++;
}
函数dec(elem)
{
如果(元素值>1)
{
要素价值;
}
}
此表单为html格式:

<form method="POST" action= "tameio.php"  >
<input type="hidden" value="0" id="counter" name="counter">
<input type = "submit" value = "NextPage" name = "submit" onClick="inc(document.getElementById('counter')); ">
<input type = "submit" value = "PreviousPage" name = "submit" onClick="dec(document.getElementById('counter'));">
</form>

下面是php:

<?php
if(isset($_POST['submit']))
{
    echo $_POST['counter'];
    if($_POST['submit'] == 'NextPage'){
    ...
        }
}
?>

所以问题是,在我单击NextPage按钮后,0变为1,但它没有存储在表单中,所以在html上再次变为0。如果我重新单击它,它将再次发送1。我应该改用ajax吗?

像这样试试-

<script>
    function inc(elem)
    {
        document.getElementById('counter').value = elem.value +1; 
    }
    function dec(elem)
    {
        if(elem.value>1)
        {
            document.getElementById('counter').value = elem.value -1;
        }
    }
</script>

功能公司(elem)
{
document.getElementById('counter')。value=elem.value+1;
}
函数dec(elem)
{
如果(元素值>1)
{
document.getElementById('counter')。value=elem.value-1;
}
}

没有必要这样做

<form method="POST" action= "tameio.php"  >
<input type="hidden" value="<?=$current_page?>" id="counter" name="counter">
<input type = "submit" value = "NextPage" name = "submit" onClick="inc(document.getElementById('counter')); ">
<input type = "submit" value = "PreviousPage" name = "submit" onClick="dec(document.getElementById('counter'));">
</form>


我想你要找的是。注意:未定义变量:当前页面。如果我把它定义为0,我仍然得到1
<?php
if(isset($_POST['submit']))
{
    if($_POST['submit'] == 'NextPage')
    {
        $current_page = $_POST['counter'] + 1;
    } else {
        $current_page = $_POST['counter'] - 1;
    }
} else {
    $current_page = 1;
}
// Fetch the page data based on the current page
...

?>>
<a href="tamieo.php?page=<?=$current_page - 1?>">Previous Page</a> |
<a href="tamieo.php?page=<?=$current_page + 1?>">Next Page</a>
<?php

    if(isset($_GET['page']) && $_GET['page'] > 0)
        $current_page = (int) $_GET['page'];
    else
        $current_page = 1;