求问一个js点击a标签前弹出提示

Posted 2023-04-30

我在<input typle="submit" onclick="return test()" />这个标签里点击时候会弹出提示
但是在<a onclick="return test()" >XXXXX</a>在a标签里就不行了，请问是a标签不可这样用还是我哪里写错了/
是这样的test() 函数的作用类似confirm()，点击点击之前弹出个确定或者取消，如果确定就继续执行下面，取消就不执行了。发现a标签这样写不行

参考技术A <input typle="submit" onclick="return test()" />
<a onclick="return test()" >XXXXX</a>

比下面的a多出发了form的submit事件，
鬼知道你的提示是不是监听submit弹出来的！ 参考技术B <a href='javascript:return test()'>xxxx</a> 参考技术C 本人亲自测试代码如下：
<script>
function test()

alert("a")

</script>
<a onclick="return test()" >XXXXX</a>
没有问题，不知道你是什么原因，就算你不加return也没问题，简写
<a onclick="test()" >XXXXX</a>本回答被提问者和网友采纳

谁能帮写一个点击链接自动弹出提示窗口的js代码？

我想在 Discuz! 5.0.0论坛程序中加入一段js代码，让会员点击下载附件前自动弹出提示窗口，请问怎么写？

你需要修改attachment.php文件 在根目录下
在$attachexists = $ispaid = FALSE;下面添加
if (!empty($checktwo))

在最末尾的?>前添加
else
echo "<script>alert('写上你要提示的内容')</script>";
echo "<META HTTP-EQUIV=\"Refresh\" CONTENT=\"0;URL=$PHP_SELF?checktwo=1&aid=$aid\">";


我在本机架设Discuz! 5.0.1调试通过了

完整代码如下：
<?php

/*
[Discuz!] (C)2001-2006 Comsenz Inc.
This is NOT a freeware, use is subject to license terms

$RCSfile: attachment.php,v $
$Revision: 1.13 $
$Date: 2006/08/11 06:51:07 $
*/

require_once './include/common.inc.php';

$discuz_action = 14;

if($attachrefcheck && $_SERVER['HTTP_REFERER'] && preg_replace("/https?:\/\/([^\/]+).*/i", "\\1", $_SERVER['HTTP_REFERER']) != $_SERVER['HTTP_HOST'])
//header("Location: $boardurlimages/common/invalidreferer.gif");
showmessage('attachment_referer_invalid', NULL, 'HALTED');


/*
$query = $db->query("SELECT a.*, t.fid, p.authorid FROM $tablepreattachments a, $tableprethreads t, $tablepreposts p
WHERE a.aid='$aid' AND t.tid=a.tid AND p.pid=a.pid AND t.displayorder>='0' AND p.invisible='0'");
$attach = $db->fetch_array($query);
*/

periodscheck('attachbanperiods');
$attachexists = $ispaid = FALSE;
if (!empty($checktwo))
if(!empty($aid))
$query = $db->query("SELECT * FROM $tablepreattachments WHERE aid='$aid'");
if($attach = $db->fetch_array($query))
$query = $db->query("SELECT tid, fid, price, special FROM $tableprethreads WHERE tid='$attach[tid]' AND displayorder>='0'");
$thread = $db->fetch_array($query);
if($thread['fid'])
$query = $db->query("SELECT authorid FROM $tablepreposts WHERE pid='$attach[pid]' AND invisible='0'");
if($db->num_rows($query))
$attach['authorid'] = $db->result($query, 0);
$attachexists = TRUE;





if($allowgetattach && ($attach['readperm'] && $attach['readperm'] > $readaccess) && $adminid <= 0 && !($discuz_uid && $discuz_uid == $attach['authorid']))
showmessage('attachment_forum_nopermission', NULL, 'NOPERM');


if(!$thread['special'] && $thread['price'] > 0 && (!$discuz_uid || ($discuz_uid && $discuz_uid != $attach['authorid'] && $adminid <=0)))
$query = $db->query("SELECT uid FROM $tableprepaymentlog WHERE uid='$discuz_uid' AND tid='$attach[tid]'");
if($db->result($query, 0))
$ispaid = TRUE;
else
showmessage('attachment_payto', 'viewthread.php?tid='.$attach['tid']);



$filename = $attachdir.'/'.$attach['attachment'];

if(is_readable($filename) && $attachexists)

$query = $db->query("SELECT f.viewperm, f.getattachperm, f.getattachcredits, a.allowgetattach FROM $tablepreforumfields f
LEFT JOIN $tablepreaccess a ON a.uid='$discuz_uid' AND a.fid=f.fid
WHERE f.fid='$thread[fid]'");
$forum = $db->fetch_array($query);

if(!$ispaid)
if(!$forum['allowgetattach'])
if(!$forum['getattachperm'] && !$allowgetattach)
showmessage('group_nopermission', NULL, 'NOPERM');
elseif(($forum['getattachperm'] && !forumperm($forum['getattachperm'])) || ($forum['viewperm'] && !forumperm($forum['viewperm'])))
showmessage('attachment_forum_nopermission', NULL, 'NOPERM');




if(!($isimage = preg_match("/^image\/.+/", $attach['filetype'])))
checklowerlimit($creditspolicy['getattach'], -1);


if(empty($noupdate))
if($delayviewcount == 2 || $delayviewcount == 3)
$logfile = './forumdata/cache/cache_attachviews.log';
if(substr($timestamp, -1) == '0')
require_once DISCUZ_ROOT.'./include/misc.func.php';
updateviews('attachments', 'aid', 'downloads', $logfile);


if(@$fp = fopen(DISCUZ_ROOT.$logfile, 'a'))
fwrite($fp, "$aid\n");
fclose($fp);
elseif($adminid == 1)
showmessage('view_log_invalid');

else
$db->query("UPDATE $tablepreattachments SET downloads=downloads+'1' WHERE aid='$aid'", 'UNBUFFERED');



if(!$isimage)
$forum['getattachcredits'] = $forum['getattachcredits'] ? unserialize($forum['getattachcredits']) : array();
$getattachcredits = $forum['getattachcredits'] ? $forum['getattachcredits'] : $creditspolicy['getattach'];
updatecredits($discuz_uid, $getattachcredits, -1);


$filesize = filesize($filename);

ob_end_clean();
header('Cache-control: max-age=31536000');
header('Expires: '.gmdate('D, d M Y H:i:s', $timestamp + 31536000).' GMT');
header('Content-Encoding: none');
$attach['filename'] = (strtolower($charset) == 'utf-8' && strexists($_SERVER['HTTP_USER_AGENT'], 'MSIE')) ? urlencode($attach['filename']) : $attach['filename'];

if($isimage && !empty($noupdate))
header('Content-Disposition: inline; filename='.$attach['filename']);
else
header('Content-Disposition: attachment; filename='.$attach['filename']);

header('Content-Type: '.$attach['filetype']);

@$fp = fopen($filename, 'rb');
@flock($fp, 2);
$attachment = @fread($fp, $filesize);
@fclose($fp);

echo $attachment;

else

showmessage('attachment_nonexistence');


else
echo "<script>alert('$PHP_SELF')</script>";
echo "<META HTTP-EQUIV=\"Refresh\" CONTENT=\"0;URL=$PHP_SELF?checktwo=1&aid=$aid\">";

?>

还有不明白的给我站内留言 enjoy it! 参考技术A 没研究过Discuz!你要先找到添加附件的页面,然后小做修改.添加附件的同时添加上你的弹出窗口.