dsff788655567 2015-07-21 15:56
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javascript'if'语句中使用的已发布变量立即消失

I have forms running on my page which post data to a php file which causes the posted item to appear in a cart:

<form method="post"><fieldset>
<input type="hidden" name="jcartToken" value="<?php echo $_SESSION['jcartToken'];?>" />
<input type="hidden" name="my-item-name" value="is716" />
<input type="hidden" name="my-item-price" value="10" />

<input id="716" type="submit" name="my-add-button" value="&nbsp" />is716</input>

</fieldset></form>

I then put a script running at the bottom of my page which essentially toggles controls so that further selections become clear based on previous selections:

if (name == 'is716') {
document.getElementById('716b').style.display = 'none';
document.getElementById('716c').style.display = 'inline';

}else{
document.getElementById('716b').style.display = 'none';
document.getElementById('716c').style.display = 'inline';}

The problem is that the above script's if statement, that name == 'is716' apparently only becomes true for a moment when you click submit. The css will change and flash for just a second, showing that the statement is indeed working and then it will disappear. I can make the changes stay by adding 'return false' but this stops the form from being submitted and the data updated, which completely misses the point. Is there a way to both submit the data but also have the value 'stick'?

How can I make this change last until the statement changes again?

edit: Here is the page's code: 

<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
<head>
    <meta http-equiv="content-type" content="text/html; charset=utf-8" />
    <title>jCart - Free Ajax/PHP shopping cart</title>
    <link rel="stylesheet" type="text/css" media="screen, projection" href="style.css" />
    <link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/font-awesome/4.3.0/css/font-awesome.min.css">
    <link rel="stylesheet" type="text/css" media="screen, projection" href="jcart/css/jcart.css" />
    <script type='text/javascript' src='http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js'> </script>

    <style type="text/css"> 
        input.add {
        background-image: url('off.png');
        width: 12px;
        height: 12px;
        border: 0;
        cursor: pointer;
                }
                </style>
</head>
<body>
<div id="wrapper">
        <div id="sidebar">
        <div id="jcart"><?php $jcart->display_cart();?></div>
        </div>
        <div id="content">

            <form method="post"><fieldset>
                    <input type="hidden" name="jcartToken" value="<?php echo $_SESSION['jcartToken'];?>" />
                        <input type="hidden" name="my-item-id" value="1" />
                    <input type="hidden" name="my-item-name" value="is716" />
                    <input type="hidden" name="my-item-price" value="5000" />
                    <input type="hidden" name="my-item-partn" value="716" />
                    <input type="hidden" name="my-item-qty" value="1" size="3" />


        <input id="716a" type="submit" name="my-add-button" class="add" value="&nbsp" />
        <a id="716b" href="addtocart.php?jcartRemove[]=1" /><img src="on.png"></a> &nbsp Apples $5<br>
        <br></fieldset></form>

        <div class="clear"></div>

        <?php
        //echo '<pre>';
        //var_dump($_SESSION['jcart']);
        //echo '</pre>';
        ?>
    </div>
        <div class="clear"></div>
</div>



    <script type='text/javascript'>

        $(document).ready(function() { 
        $('input[name=my-add-button]').change(function(){
        $('form').submit();
        });
        });

    </script>
    <script type="text/javascript">
        $('#720').click(function() {
        $('#720click').click();
        });
    </script>
    <script type='text/javascript'>
window.onload = function() {
var myItemName = <?php echo (isset($_POST["my-item-name"])? $_POST["my-item-name"] : ""); ?>;
if (myItemName == "is716") {
    document.getElementById('716a').style.display = 'none';
    document.getElementById('716b').style.display = 'inline';
    }
}

That pushes to another page: jcart.php

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2条回答 默认 最新

  • dpdjv9559 2015-07-21 16:35
    关注

    Like Suman said your page is getting submitted, therefore the style reloads with the page so any changes made in the page session to your style will be reset.

    A solution to your problem would be to set session flags in your form's php target page. You could do this like:

    <?php
    if (isset($_POST["my-item-name"]) {
        session_start();
        $_SESSION["my-item-name"] = $_POST["my-item-name"];
    }
?>

    And then on your cart page you would echo the session variable into a JavaScript that will toggle the styling of your page as necessary:

    <?php session_start(); ?>
window.onload = function() {
    var myItemName = <?php echo $_SESSION["my-item-name"]; ?>;
    if (myItemName == "is716") {
        document.getElementById('716b').style.display = 'none';
        document.getElementById('716c').style.display = 'inline';
    }
}

    Hopefully this is what you are looking for.

    EDIT: For if your target page is the same page you could simplify this by having your javascript look like this:

    window.onload = function() {
    var myItemName = "<?php echo (isset($_POST["my-item-name"])? $_POST["my-item-name"] : ""); ?>";
    if (myItemName == "is716") {
        document.getElementById('716b').style.display = 'none';
        document.getElementById('716c').style.display = 'inline';
    }
}
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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