我想做铁饼/ reddit /喜欢评论系统,我的评论数据库中有一个“id_answer”(由defaut设置为0)字段,当用户回答另一个评论时,该字段是父评论的“id”.
我有一个数组中的线程的注释,但我不知道如何过滤每个循环过滤器得到这样的东西：
comment lvl 1 ($array[id_answer] is 0)
——- comment lvl 2 ($array[id_answer] is id_of_level_one_comment)
————— comment lvl 3 …
在数据库中使用三个字段;
>“id”,每个评论都是唯一的
>“parent_id”,它是0(顶级注释)或父注释的“id”
>“thread_id”,这是你评论的内容的id
假设您要显示ID为“123”的新闻文章的评论树
从mysql中选择时,使用此thread_id选择所有内容：
SELECT id,parent FROM comments WHERE thread_id = 123
然后你应该预先解析你的数组,让孩子给他们的父母评论,并使用递归显示来显示每个评论及其子列表.
举个例子：
// getting the comments from MysqL,I'm obvIoUsly not bothering
// to check the return value,but in your code you should do it
$result = MysqLi_query("SELECT id,parent FROM comments WHERE thread_id = 123");
$comments = array();
while ($row = MysqLi_fetch_array($result)) {
$row['childs'] = array();
$comments[$row['id']] = $row;
}
// This is the array you get after your MysqL query
// Order is non important,I put the parents first here simply to make it clearer.
/*
$comments = array(
// some top level (parent == 0)
1 => array('id' => 1,'parent' => 0,'childs' => array()),5 => array('id' => 5,2 => array('id' => 2,10 => array('id' => 10,// and some childs
3 => array('id' => 3,'parent' => 1,6 => array('id' => 6,'parent' => 2,4 => array('id' => 4,7 => array('id' => 7,'parent' => 3,8 => array('id' => 8,'parent' => 7,9 => array('id' => 9,'parent' => 6,);
*/
// Now loop your comments list,and everytime you find a child,push it
// into its parent
foreach ($comments as $k => &$v) {
if ($v['parent'] != 0) {
$comments[$v['parent']]['childs'][] =& $v;
}
}
unset($v);
// delete the childs comments from the top level
foreach ($comments as $k => $v) {
if ($v['parent'] != 0) {
unset($comments[$k]);
}
}
// Now we display the comments list,this is a basic recursive function
function display_comments(array $comments,$level = 0) {
foreach ($comments as $info) {
echo str_repeat('-',$level + 1).' comment '.$info['id']."\n";
if (!empty($info['childs'])) {
display_comments($info['childs'],$level + 1);
}
}
}
display_comments($comments);
这给出了以下结果：
- comment 1 -- comment 3 --- comment 7 ---- comment 8 - comment 5 - comment 2 -- comment 6 --- comment 9 -- comment 4 - comment 10
我把ORDER BY等等留给你,因为它不应该造成任何问题.