本文实例讲述了php从数据库查询结果生成树形列表的方法。分享给大家供大家参考。具体分析如下：

本代码可以从数据库读取数据生成一个类似于windows的资源管理器的树形列表

<?php/* Here are the database definitions (for Solid) that i use in this code. * It should not be hard to adapt it to another database. *//*CREATE TABLE dirent_types ( id INTEGER NOT NULL, icon VARCHAR(50), name VARCHAR(50), PRIMARY KEY(id));INSERT INTO dirent_types VALUES(1, "folderclosed", "Directory");INSERT INTO dirent_types VALUES(2, "document", "File");CREATE TABLE directory ( id INTEGER NOT NULL, parent INTEGER REFERENCES directory(id), name VARCHAR(200), icon VARCHAR(50), type INTEGER REFERENCES dirent_types(id), url VARCHAR(200), PRIMARY KEY(id));DROP INDEX directory_idx;CREATE UNIQUE INDEX directory_idx ON directory(parent, name);CREATE SEQUENCE dirent_id;"CREATE PROCEDURE insert_dir_entry (name VARCHAR, parent INTEGER, type INTEGER) RETURNS(id INTEGER)BEGIN EXEC SQL WHENEVER SQLERROR ABORT; EXEC SEQUENCE dirent_id.NEXT INTO id; EXEC SQL PREPARE c_insert INSERT INTO directory (id, parent, type, name) VALUES(?, ?, ?, ?); EXEC SQL EXECUTE c_insert USING (id, parent, type, name); EXEC SQL DROP c_insert;END";CALL insert_dir_entry("My Computer", NULL, 1);CALL insert_dir_entry("Network Neighbourhood", NULL, 1);CALL insert_dir_entry("lucifer.guardian.no", 2, 1);CALL insert_dir_entry("rafael.guardian.no", 2, 1);CALL insert_dir_entry("uriel.guardian.no", 2, 1);CALL insert_dir_entry("Control Panel", NULL, 1);CALL insert_dir_entry("Services", 6, 1);CALL insert_dir_entry("Apache", 7, 2);CALL insert_dir_entry("Solid Server 2.2", 7, 2);*/function icon($icon, $name = "", $width = 0, $height = 0) { global $DOCUMENT_ROOT; $icon_loc = "/pics/menu"; $file = "$DOCUMENT_ROOT$icon_loc/$icon.gif"; if (!$width || !$height) { $iconinfo = getimagesize($file); if (!$width) { $width = $iconinfo[0]; } if (!$height) { $height = $iconinfo[1]; } } printf( "<img%s border=0 align=top src="/pics/menu/%s.gif" ". "width="%d" height="%d">", $name ? " name="$name"" : "", $icon, $width, $height);}function display_directory($parent,$showdepth=0,$ancestors=false){ global $child_nodes, $node_data, $last_child; reset($child_nodes[$parent]); $size = sizeof($child_nodes[$parent]); $lastindex = $size - 1; if (!$ancestors) { $ancestors = array(); } $depth = sizeof($ancestors); printf( "<div id="node_%d" class="dirEntry" visibility="%s">", $parent, $showdepth > 0 ? "show" : "hide"); while (list($index, $node) = each($child_nodes[$parent])) { for ($i = 0; $i < $depth; $i++) { $up_parent = (int)$node_data[$ancestors[$i]][ "parent"]; $last_node_on_generation = $last_child[$up_parent]; $uptree_node_on_generation = $ancestors[$i]; if ($last_node_on_generation == $uptree_node_on_generation) { icon( "blank"); } else { icon( "line"); } } if ($child_nodes[$node]) { // has children, i.e. it is a folder $conn_icon = "plus"; $expand = true; } else { $conn_icon = "join"; $expand = false; } if ($index == $lastindex) { $conn_icon .= "bottom"; } elseif ($depth == 0 && $index == 0) { $conn_icon .= "top"; } if ($expand) { printf( "<a href="javascript:document.layers["node_%d"].visibility="show"">", $node); } icon($conn_icon, "connImg_$node"); if ($expand) { print( "</a>"); } $icon = $node_data[$node][ "icon"]; if (!$icon) { $type = $node_data[$node][ "type"]; $icon = $GLOBALS[ "dirent_icons"][$type]; } icon($icon, "nodeImg_$node"); $name = $node_data[$node][ "name"]; printf( "?<font size="%d">%s</font><br%c>", -1, $name, 10); if ($child_nodes[$node]) { $newdepth = $showdepth; if ($newdepth > 0) { $newdepth--; } $new_ancestors = $ancestors; $new_ancestors[] = $node; display_directory($node, $newdepth, $new_ancestors); } } print( "</div>");}function setup_directory($parent, $maxdepth){ global $dirent_icons, $child_nodes, $node_data, $last_child; $dirent_icons = sql_assoc("SELECT id,icon FROM dirent_types"); $query = "SELECT id,parent,type,icon,name ". "FROM directory ". "ORDER BY parent,name"; $child_nodes = array(); $node_data = array(); $res = sql($query); while (list($id,$parent,$type,$icon,$name)=db_fetch_row($res)){ $child_nodes[(int)$parent][] = $id; $node_data[$id] = array( "id" => $id, "parent" => $parent, "type" => $type, "icon" => $icon, "name" => $name); $last_child[(int)$parent] = $id; }}?>

希望本文所述对大家的php程序设计有所帮助。