Web development is the mainstream of distributed program development in the future. Usually web development involves dealing with the database. The client reads from the server and usually displays it in the form of paging. It can be read page by page. Both convenient and beautiful. Therefore, writing paging programs is an important part of web development. Here, we will study the writing of paging programs together.
1. After using ajax to post data to the background page, you must connect to the database again. Do not think that it is enough to connect with the previous session.
2. In order to process the returned garbled code Question, I added header("Content-Type:text/html;charset=GB2312"); and it was displayed normally. Later, when I checked it in firefox, I was prompted to download this webpage. After searching a lot of information on the Internet, I got a My vague understanding is that the web page code has grammatical errors. For security reasons, Firefox will not display it directly but prompts for downloading. I rechecked the statement just now and found that I had written an extra "\" and replaced it. The problem will be solved after removing it, haha, so if you encounter such a problem, check the html tag carefully. After all, Firefox is not as smart as IE
3. Finally, as a web site developer, you must be responsible. Don't think that everything will be fine if you pass the test under IE. After all, not everyone uses IE. You have to do more tests under other browsers to show your professionalism.
ajax script:
The code is as follows:
<script> function viewpage(p){ if(window.XMLHttpRequest){ var xmlReq = new XMLHttpRequest(); } else if(window.ActiveXObject) { var xmlReq = new ActiveXObject('Microsoft.XMLHTTP'); } var formData = "page="+p; xmlReq.onreadystatechange = function(){ if(xmlReq.readyState == 4){ document.getElementById('content2').innerHTML = xmlReq.responseText; } } xmlReq.open("post", "hotel_list.php", true); xmlReq.setRequestHeader("Content-Type", "application/x-www-form-urlencoded"); xmlReq.send(formData); return false; } </script>
Call:
The code is as follows:
header("Content-Type:text/html;charset=GB2312"); $pagesize=10; //echo $_POST['page']; $result = mysql_query("Select count(DISTINCT hotelname) FROM ".TBL_HOTELS); $myrow = mysql_fetch_array($result); $numrows=$myrow[0]; $pages=intval($numrows/$pagesize); if ($numrows%$pagesize) $pages++; if (isset($_POST['page'])){ $page=intval($_POST['page']); } else{ //设置为第一页 $page=1; } $first=1; $prev=$page-1; $next=$page+1; $last=$pages; //计算记录偏移量 $offset=$pagesize*($page - 1); //读取指定记录数 $result=mysql_query("select `hotelname` , count( * ) from ".TBL_HOTELS." GROUP BY `hotelname` order by id desc limit $offset,$pagesize"); $num = mysql_num_rows($result); while ($row = mysql_fetch_array($result,MYSQL_NUM)) { $hotelname[] = $row[0]; $countpeople[] = $row[1]; } for($a=0;$a<$num;$a++) { //$result=mysql_query("select count(title) from " . TBL_Comments ." where `title`=\"".$title[$a]."\""); //$row = mysql_fetch_row($result); echo "<TABLE style=\"MARGIN-BOTTOM: 20px\" cellSpacing=0 cellPadding=0 width=100% border=0>\n"; echo "<TBODY>\n"; echo "<TR>\n"; echo "<TD style=\"PADDING-TOP: 5px\" vAlign=top align=left width=80>\n"; //rating_bar($title[$a],5); echo "</TD>\n"; echo "<TD style=\"PADDING-TOP: 5px\" align=left width=100%><A title=$hotelname[$a] style=\"FONT-SIZE: 14px\" href=#>$hotelname[$a]</A>\n"; echo "</TD></TR>\n"; echo " <TR>\n"; echo "<TD></TD>\n"; echo "<TD style=\"PADDING-LEFT: 0px\">\n"; echo "<IMG src=\"images/comment.gif\" border=0> 推荐人数:($countpeople[$a]) |\n"; echo "<SPAN>平均分:<STRONG></STRONG> (".$count."票) | 评论数:()</SPAN>\n"; echo "</TD></TR></TBODY></TABLE>\n"; } echo "<TABLE style=\"MARGIN-TOP: 30px\" cellSpacing=0 cellPadding=0 width=\"100%\""; echo "border=0>"; echo "<TBODY><TR><TD colSpan=3 height=20>"; echo "<p align=center>"; echo "<P align=left><FONT color=red>第".$page."页/总".$pages."页 | 总".$numrows."条</FONT> | "; if ($page>1) echo "<a onclick=\"viewpage(".$first.")\" href='#'>首页</a> | "; if ($page>1) echo "<a onclick=\"viewpage(".$prev.")\" href='#'>上页</a> | "; if ($page<$pages) echo "<a onclick=\"viewpage(".$next.")\" href='#'>下页</a> | "; if ($page<$pages) echo "<a onclick=\"viewpage(".$last.")\" href='#'>尾页</a>"; echo "转到第 <INPUT maxLength=3 size=3 value=1 name=goto_page> 页 <INPUT hideFocus onclick=\"viewpage(document.all.goto_page.value)\" type=button value=Go name=cmd_goto>"; echo "</P></p></TD></TR></TBODY></TABLE>";
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