使用Javascript设置隐藏字段值；使用PHP post方法发送数据 [英] Set hidden field value using Javascript; use PHP post method to send the data

问题描述

我需要获取用户的屏幕分辨率并将其保存在我的数据库中.

I need to get the user's screen resolution and save it my database.

我正在做的是:我有一个名为的Javascript函数，它获取信息并将值传递给隐藏的表单字段.这是功能:

What I'm doing is this: I have a Javascript function called with that gets the info and passes the value to a hidden form field. This is the function:

<script type="text/javascript">

function getUserData(){

var s_width=screen.width
var s_height=screen.height
document.getElementById('screen_width').value=s_width
document.getElementById('screen_height').value=s_height

}

</script>

表格:

<form name="login" id="login" action="memberlogin.php" method="post">
<input type="hidden" id="screen_width" name="screen_width">
<input type="hidden" id="screen_height" name="screen_height">
<table style="margin-top:9px;">
<tr><td width="200px"><input type="text" name="username" style="width:100%"/></td></tr>
<tr><td width="200px"><input type="password" name="password" style="width:100%"/></td></tr>
<tr><td><input type="submit" name="submit" value="Log In" /></td></tr>
</table>
</form>

表单提交到同一页面.当我单击提交"并尝试回显$ _POST ['screen_width']和$ _POST ['screen_height']的值时，什么都没有发生.但是当我重新提交它时，值就存在了.有人可以告诉我我在做什么错吗?如果您有其他解决方案，也将不胜感激.

The form submits to the same page. When I click 'submit' and try to echo the value of $_POST['screen_width'] and $_POST['screen_height'], nothing happens. But when I re-submit it, the values are there. Can someone tell me what am I doing wrong? If you have an alternative solution, it would be equally appreciated.

推荐答案

我自己解决了这个问题，这只是在加载元素后调用函数的问题.

Solved it myself, it was just a matter of calling the function after loading the element.

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