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HomeBackend DevelopmentPHP Tutorial 怎的讲javascript产生的值传到PHP中

怎样讲javascript产生的值传到PHP中?
我的页面是PHP页面,用javascript实现下拉列表的onchange()事件,我怎样将列表的新值送到php代码中.
我试着用cookie,但每次只能传第一次的值.例如:
第一次选择userid0,php可以得到;但再选择userid1时,php中还是得到第一次的值.
请教怎么解决?
SetCookie("userID",current_user_id);
alert(document.cookie);


$file_exist=0;
$imagefile='user'.$userID.".jpg";
if(file_exists($imagefile))
$file_exist=1;
?>

alert(" echo $HTTP_COOKIE_VARS['userID'] ?>");

------解决方案--------------------
AJAX可以实现
------解决方案--------------------

PHP code

//index.php
<?php echo $_GET['value'];?><br>
<select onchange="window.location='index.php?value='+this.value;">
<option value="1">1</option>
<option value="2">2</option>
</select>
<br><font color="#e78608">------解决方案--------------------</font><br>可以提交给php页面,也可以用ajax来实现.当然也仍旧可以用cookie实现.<br>把你的部分代码贴出来看一下.
<br><font color="#e78608">------解决方案--------------------</font><br>
先把值用session存储一下,然后再把session的值赋给php
<br><font color="#e78608">------解决方案--------------------</font><br>楼上正解
<br><font color="#e78608">------解决方案--------------------</font><br>4楼是正确的,而且很简单.当然也可以用AJAX
<br><font color="#e78608">------解决方案--------------------</font><br>session存储简单 <div class="clear">
                 
              
              
        
            </div>
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