Complete homepage code implementation of simple book lending system developed in PHP

This section implements the home page function code as shown below

The main page is index.php, including category selection, user exit, borrowing and returning books, and various paging show.

<?php
include("config.php");
?>
<html>
<head>
   <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
   <title>图书管理系统主页面</title>
   <style>
      body,td,th {font-family: 微软雅黑;font-size: 9px;color: #222;}
      body {background-color: #FFFFFF;line-height:20px;}
      a:link {color: #222;text-decoration: none;}
      a:visited {text-decoration: none;color: #222;}
      a:hover {text-decoration: underline;color: #FF0000;}
      a:active {text-decoration: none;color: #999999;}
   </style>
</head>
<body>
<?php include("head.php");?>
<table width="782" border="0" align="center" cellpadding="0" cellspacing="0">
  <tr>
   <td height="22">
    <?php
     $pagesize=5;  //每页显示5条数据
     if(!urldecode($_GET['proid'])){
     //urldecode()函数将 URL 编码后字符串还原成未编码的样子。编码使用 %## 的格式
     $sql="select * from yx_books order by id desc";  //倒序排列
     }else{
     $sql="select * from yx_books where type='".urldecode($_GET['proid'])."'";
     //将查询出来的书目类别中文字转换为编码形式
     }
     $rs=mysqli_query($link,$sql);
     $recordcount=mysqli_num_rows($rs);  //输出查询的总数
     //mysql_num_rows() 返回结果集中行的数目。此命令仅对 SELECT 语句有效。
     $pagecount=($recordcount-1)/$pagesize+1;  //计算总页数
     $pagecount=(int)$pagecount;
     $pageno=empty($_GET["pageno"])?'':$_GET["pageno"];  //当前页

     if($pageno=="")  //当前页为空时显示第一页
     {
      $pageno=1;
     }
     if($pageno<1)   //当前页小于第一页时显示第一页
     {
      $pageno=1;
     }
     if($pageno>$pagecount)  //当前页数大于总页数时显示总页数
     {
      $pageno=$pagecount;
     }
     $startno=($pageno-1)*$pagesize;  //每页从第几条数据开始显示

     if(!urldecode($_GET["proid"])){
       $sql="select * from yx_books order by id desc limit $startno,$pagesize";
     }else{
     $sql="select * from yx_books where type='".urldecode($_GET['proid'])."' 
     order by id desc limit $startno,$pagesize";
     }
     $rs=mysqli_query($link,$sql);
     ?>
     <table width="100%" border="0" align="center" cellpadding="0" cellspacing="1" bgcolor="#CCCCCC">
      <tr>
       <td width="88" height="30" align="center" bgcolor="#FFFFFF" class="line2">ID</td>
       <td width="103" align="center" bgcolor="#FFFFFF" class="line2">书名</td>
       <td width="77" align="center" bgcolor="#FFFFFF" class="line2">价格</td>
       <td width="152" align="center" bgcolor="#FFFFFF" class="line2">入库时间</td>
       <td width="107" align="center" bgcolor="#FFFFFF" class="line2">类别</td>
        <td width="126" align="center" bgcolor="#FFFFFF" class="line2">现有数量(本)</td>
       <td width="121" align="center" bgcolor="#FFFFFF" class="line2">操作</td>
      </tr>
       <?php
         if(!empty($rs)){
             while($rows=mysqli_fetch_array($rs))
          {
        ?>
        <tr>
         <td height="30" align="center" bgcolor="#FFFFFF"><?php echo $rows["id"];?></td>
         <td align="center" bgcolor="#FFFFFF"><?php echo $rows["name"];?></td>
         <td align="center" bgcolor="#FFFFFF"><?php echo $rows["price"];?></td>
         <td align="center" bgcolor="#FFFFFF"><?php echo $rows["uploadtime"];?></td>
         <td align="center" bgcolor="#FFFFFF"><?php echo $rows["type"];?></td>
         <td align="center" bgcolor="#FFFFFF"><?php echo $rows["leave_number"];?></td>
          <td align="center" bgcolor="#FFFFFF" class="line2">
        <?php
         $rs2=mysqli_query($link,"select * from lend where book_id='".$rows['id']."' 
         and user_id='".$_SESSION['id']."'");
         $rows2=mysqli_fetch_assoc($rs2);
         if($rows2['book_id']){
          echo "<font color='red'>您已借阅</font>&nbsp;&nbsp;
          <a href=huanshu.php?book_id=".$rows['id'].">我要还书</a>";
           }else{
          if($rows["leave_number"]==0){
          echo "<font color='#cccc00'>该书已借完</font>";
           }else{
           echo "<a href=jieshu.php?book_id=".$rows['id'].">我要借书</a>";
           }
          }
        ?> </td>
        </tr>
        <?php
          }
         }
         ?>
       </table>
     <table width="100%" border="0" align="center" cellpadding="2" cellspacing="1" bgcolor="#CCCCCC">
        <tr>
          <td height="35" align="center" bgcolor="#FFFFFF">
         <?php
          if($pageno==1)
          {
         ?>
         首页 | 上一页 |
      <?php if($pageno+1<= $pagecount) { ?>
       <a href="index.php?proid=<?php echo empty($_GET['proid'])?'':urlencode($_GET['proid']);?>
        &pageno=<?php echo $pageno + 1 ?>">下一页</a> |
        <a href="index.php?proid=<?php echo empty($_GET['proid'])?'':urlencode($_GET['proid']);?>
      &pageno=<?php echo $pagecount ?>">末页</a>
      <?php
        }
      }
       else if($pageno==$pagecount)
      {
      ?>
      <a href="index.php?proid=<?php echo urlencode($_GET['proid']);?>&pageno=1">首页</a> |
      <a href="index.php?proid=<?php echo urlencode($_GET['proid']);?>
      &pageno=<?php echo $pageno-1?>">上一页</a> | 下一页 | 末页
      <?php
       }
          else
       {
      ?>
      <a href="index.php?proid=<?php echo urlencode($_GET['proid']);?>&pageno=1">首页</a> |
      <a href="index.php?proid=<?php echo urlencode($_GET['proid']);?>
      &pageno=<?php echo $pageno-1?>">上一页</a> |
      <a href="index.php?proid=<?php echo urlencode($_GET["proid"]);?>
      &pageno=<?php echo $pageno+1?>" class="forumRowHighlight">下一页</a> |
      <a href="?pageno=<?php echo $pagecount?>">末页</a>
      <?php
      }
      ?>
      &nbsp;页次：<?php echo $pageno ?>/<?php echo $pagecount ?>
      页&nbsp;共有<?php echo $recordcount?>条信息</td>
      </tr>
     </table></td></tr>
</table>
<table width="782" height="30" border="0" align="center" cellpadding="2" cellspacing="1" bgcolor="#CCCCCC">
   <tr>
      <td height="19" align="center">&nbsp;Copyright @ 2013-2016</td>
   </tr>
</table>
</body>
</html>

new file

 <?php
include("config.php");
?>
<html>
<head>
 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 <title>图书管理系统主页面</title>
 <style>
 body,td,th {font-family: 微软雅黑;font-size: 9px;color: #222;}
 body {background-color: #FFFFFF;line-height:20px;}
 a:link {color: #222;text-decoration: none;}
 a:visited {text-decoration: none;color: #222;}
 a:hover {text-decoration: underline;color: #FF0000;}
 a:active {text-decoration: none;color: #999999;}
 </style>
</head>
<body>
<?php include("head.php");?>
<table width="100%" border="0" align="center" cellpadding="0" cellspacing="0">
 <tr>
 <td height="22">
 <?php
 $pagesize=5; //每页显示5条数据
 if(!urldecode($_GET['proid'])){
 //urldecode()函数将 URL 编码后字符串还原成未编码的样子。编码使用 %## 的格式
 $sql="select * from yx_books order by id desc"; //倒序排列
 }else{
 $sql="select * from yx_books where type='".urldecode($_GET['proid'])."'";
 //将查询出来的书目类别中文字转换为编码形式
 }
 $rs=mysqli_query($link,$sql);
 $recordcount=mysqli_num_rows($rs); //输出查询的总数
 //mysql_num_rows() 返回结果集中行的数目。此命令仅对 SELECT 语句有效。
 $pagecount=($recordcount-1)/$pagesize+1; //计算总页数
 $pagecount=(int)$pagecount;
 $pageno=empty($_GET["pageno"])?'':$_GET["pageno"]; //当前页

 if($pageno=="") //当前页为空时显示第一页
 {
 $pageno=1;
 }
 if($pageno<1) //当前页小于第一页时显示第一页
 {
 $pageno=1;
 }
 if($pageno>$pagecount) //当前页数大于总页数时显示总页数
 {
 $pageno=$pagecount;
 }
 $startno=($pageno-1)*$pagesize; //每页从第几条数据开始显示

 if(!urldecode($_GET["proid"])){
 $sql="select * from yx_books order by id desc limit $startno,$pagesize";
 }else{
 $sql="select * from yx_books where type='".urldecode($_GET['proid'])."' 
 order by id desc limit $startno,$pagesize";
 }
 $rs=mysqli_query($link,$sql);
 ?>
 <table width="100%" border="0" align="center" cellpadding="0" cellspacing="1" bgcolor="#CCCCCC">
 <tr>
 <td width="" height="30" align="center" bgcolor="#FFFFFF" class="line2">ID</td>
 <td width="" align="center" bgcolor="#FFFFFF" class="line2">书名</td>
 <td width="" align="center" bgcolor="#FFFFFF" class="line2">价格</td>
 <td width="" align="center" bgcolor="#FFFFFF" class="line2">入库时间</td>
 <td width="" align="center" bgcolor="#FFFFFF" class="line2">类别</td>
 <td width="" align="center" bgcolor="#FFFFFF" class="line2">现有数量(本)</td>
 <td width="" align="center" bgcolor="#FFFFFF" class="line2">操作</td>
 </tr>
 <?php
 if(!empty($rs)){
 while($rows=mysqli_fetch_array($rs))
 {
 ?>
 <tr>
 <td height="30" align="center" bgcolor="#FFFFFF"><?php echo $rows["id"];?></td>
 <td align="center" bgcolor="#FFFFFF"><?php echo $rows["name"];?></td>
 <td align="center" bgcolor="#FFFFFF"><?php echo $rows["price"];?></td>
 <td align="center" bgcolor="#FFFFFF"><?php echo $rows["uploadtime"];?></td>
 <td align="center" bgcolor="#FFFFFF"><?php echo $rows["type"];?></td>
 <td align="center" bgcolor="#FFFFFF"><?php echo $rows["leave_number"];?></td>
 <td align="center" bgcolor="#FFFFFF" class="line2">
 <?php
 $rs2=mysqli_query($link,"select * from lend where book_id='".$rows['id']."' 
 and user_id='".$_SESSION['id']."'");
 $rows2=mysqli_fetch_assoc($rs2);
 if($rows2['book_id']){
 echo "<font color='red'>您已借阅</font>  
 <a href=huanshu.php?book_id=".$rows['id'].">我要还书</a>";
 }else{
 if($rows["leave_number"]==0){
 echo "<font color='#cccc00'>该书已借完</font>";
 }else{
 echo "<a href=jieshu.php?book_id=".$rows['id'].">我要借书</a>";
 }
 }
 ?> </td>
 </tr>
 <?php
 }
 }
 ?>
 </table>
 <table width="100%" border="0" align="center" cellpadding="2" cellspacing="1" bgcolor="#CCCCCC">
 <tr>
 <td height="35" align="center" bgcolor="#FFFFFF">
 <?php
 if($pageno==1)
 {
 ?>
 首页 | 上一页 |
 <?php if($pageno+1<= $pagecount) { ?>
 <a href="index.php?proid=<?php echo empty($_GET['proid'])?'':urlencode($_GET['proid']);?>
 &pageno=<?php echo $pageno + 1 ?>">下一页</a> |
 <a href="index.php?proid=<?php echo empty($_GET['proid'])?'':urlencode($_GET['proid']);?>
 &pageno=<?php echo $pagecount ?>">末页</a>
 <?php
 }
 }
 else if($pageno==$pagecount)
 {
 ?>
 <a href="index.php?proid=<?php echo urlencode($_GET['proid']);?>&pageno=1">首页</a> |
 <a href="index.php?proid=<?php echo urlencode($_GET['proid']);?>
 &pageno=<?php echo $pageno-1?>">上一页</a> | 下一页 | 末页
 <?php
 }
 else
 {
 ?>
 <a href="index.php?proid=<?php echo urlencode($_GET['proid']);?>&pageno=1">首页</a> |
 <a href="index.php?proid=<?php echo urlencode($_GET['proid']);?>
 &pageno=<?php echo $pageno-1?>">上一页</a> |
 <a href="index.php?proid=<?php echo urlencode($_GET["proid"]);?>
 &pageno=<?php echo $pageno+1?>" class="forumRowHighlight">下一页</a> |
 <a href="?pageno=<?php echo $pagecount?>">末页</a>
 <?php
 }
 ?>
  页次：<?php echo $pageno ?>/<?php echo $pagecount ?>
 页 共有<?php echo $recordcount?>条信息</td>
 </tr>
 </table></td></tr>
</table>
<table width="100%" height="30" border="0" align="center" cellpadding="2" cellspacing="1" bgcolor="#CCCCCC">
 <tr>
 <td height="19" align="center"> Copyright @ 2013-2016</td>
 </tr>
</table>
</body>
</html>

submit Reset Code

Automatic operation

Full Screen