用PHP＋MYSQL實現論壇里的分級＋分頁顯示

<?
/*存放貼子的表結構------------------------------------------------------

create table bbsrow(
    bbsrow_id int(6) not null auto_increment,  //貼子ID號
    bbsrow_auth varchar(20) not null,  //貼子作者
    bbsrow_parentid int(6),  //貼子的父親貼子ID號，如為首發貼則為空
    bbsrow_title varchar(200) not null,  //貼子標題
    bbsrow_returncount int(3),  //貼子的回復貼數，如果沒有回貼則為空
    primary key (bbsrow_id)
);
-----------------------------------------------------------------------------*/


//顯示兒子貼的遞歸函數--------------------------------------------------
function showchildren($parent_id){
    global $connect_id;
    $query="select * from bbsrow where bbsrow_parentid='" . $parent_id . "'";     
    $result_top=mysql_query($query,$connect_id);
    echo "<ul>n";
    while($myrow_child=mysql_fetch_row($result_top)){
        echo "<li>";
        echo $myrow_child[0];
        echo $myrow_child[1];
        echo $myrow_child[2];
        echo $myrow_child[3];
        echo $myrow_child[4] . "n";
        //如果回復貼數不為空，則表示有兒子貼，繼續顯示兒子貼
        if($myrow_child[4]!=''){
            showchildren($myrow_child[0]);
        }
    }
    echo "</ul>";
}
//----------------------------------------------------------------------

//連接數據庫并將所有首發貼放到$mainrow數組里----------------------------

$connect_id=mysql_connect("localhost","test","test") or die("無法連接數據庫");
mysql_select_db("bbs") or die("無法選擇數據庫");
$query="select * from bbsrow where bbsrow_parentid=''";
$result=mysql_query($query,$connect_id);

$i=0;
while($myrow=mysql_fetch_row($result)) {
    $mainrow[$i][0]=$myrow[0];
    $mainrow[$i][1]=$myrow[1];
    $mainrow[$i][2]=$myrow[2];
    $mainrow[$i][3]=$myrow[3];
    $mainrow[$i][4]=$myrow[4];
    $i++;
}
mysql_free_result($result);
//----------------------------------------------------------------------

//開始構建分頁顯示------------------------------------------------------

if($currentpage!=""){
    $page=$currentpage;
}
else{
    $page=0;
}

$pagesize=10;//每頁顯示的首發貼數！
$start=$page*$pagesize;
$end=$start+$pagesize;
if($end>$i) $end=$i;
$totalpage=$i/$pagesize;

     
$info=" 共有" . $i . "條紀錄,分" . ceil($totalpage) . "頁,當前為第" . ($page+1) . "/" . ceil($totalpage) . "頁 <br>n";
echo $info;

if($page>0) $pagestr="<a href=bbsrow.php4?currentpage=" . ($page-1) . ">上一頁</a>";
$pagestr=$pagestr . " [第 ";
     
for($i=0;$i<$totalpage;$i++){
    if($i!=$page){
        $pagestr=$pagestr . " <a href=bbsrow.php4?currentpage=" . $i . ">" . ($i+1) . "</a> ";
    }
    else{
        $pagestr=$pagestr . " " . ($i+1) . " ";
    }
}

$pagestr=$pagestr . "頁]";
     
if($page<$totalpage-1) $pagestr=$pagestr . "<a href=bbsrow.php4?currentpage=" . ($page+1) .">下一頁</a><p>n";
     
echo $pagestr;
//----------------------------------------------------------------------

//開始分級顯示----------------------------------------------------------

echo "<ul>n";
for($i=$start;$i<$end;$i++){
    echo "<li>n";
    echo $mainrow[$i][0];
    echo $mainrow[$i][1];
    echo $mainrow[$i][2];
    echo $mainrow[$i][3];
    echo $mainrow[$i][4] . "n";
    //如果回復貼數不為空，則表示有兒子貼，繼續顯示兒子貼
    if($mainrow[$i][4]!=''){
        showchildren($mainrow[$i][0]);
    }
}
echo "</ul>n";
//----------------------------------------------------------------------?>