Question

下面的代码（search.php）仅适用于分页的第一页，但是当我单击第二页时，它显示以下错误。

“注意：未定义的索引：在第15行的/opt/lampp/htdocs/testdb/search.php中搜索” **。

我也尝试使用$ _SESSION，但是它不起作用。该查询仅针对分页的第一页传递。我是编码的初学者。任何帮助或建议将非常有帮助。谢谢。

<?php        

//Database connection     
$mysqli = NEW MySQLi('localhost','root','','dbname');    

//POST data from the query search page which is to be fetched from Database    
$a=$_POST['search'];// this is line 15 of my code for which the error is appearing      
//PAGINATION          
$rpp = 25;    //records per page       
isset($_GET['page']) ? $page = $_GET['page'] : $page = 0;    
     if($page > 1) {     
           $start = ($page * $rpp) - $rpp;    
}         
 else {        
     $start = 0;    
 }    
//SQL query    
$res =$mysqli->query("SELECT * FROM t1 WHERE col4 like '$a'");    
$num = $res->num_rows;   
$totalpages = $num / $rpp;        
echo $totalpages;     //to check the no. of  total pages and if it is not whole no. then in the for loop at the end of the code add +1 with $totalpages (i.e. for($x = 1; $x <= $totalpages + 1; $x++))    

$res = $mysqli->query("SELECT * FROM t1 WHERE col4 like '$a' LIMIT $start, $rpp");      

//Fetch data from table "<table>";
echo "<table>";
while($rows = $res->fetch_assoc()){    
    $a = $rows['col1'];    
    $b = $rows['col2'];    
    $c = $rows['col3'];    
    $d = $rows['col4'];    
    echo "<tr><td>$a</td><td>$b</td><td>$c</td><td>$d</td></tr>";    
}    
echo "</table><p />";    
echo "<div class='pagination'>";    
//make link for next page in pagination

for($x = 1; $x <= $totalpages; $x++)    
{    
    echo "<a href='?page=$x'>$x</a>";     
}     
?>

<!--Below is the HTML code for the search engine:-->    
<html>    
<body>    

<h2>Search page</h2>    

<form action='search.php' method='POST'>    
<input type='text' name='search'></br></br>     

<input type='submit' name='submit' value='Submit'> </br>    
</form>    

</body>    

</html>    

<!--My data has only four columns-->
 <!--sample dataset-->
PtRNAome_1  nuclear     GCA_000001735.2     Arabidopsis thaliana : nuclear
PtRNAome_2  nuclear     GCA_000001735.2     Arabidopsis thaliana : nuclear
PtRNAome_3  nuclear     GCA_000001735.2     Arabidopsis thaliana : nuclear
PtRNAome_4  nuclear     GCA_000001735.2     Arabidopsis thaliana : nuclear
PtRNAome_5  nuclear     GCA_000001735.2     Arabidopsis thaliana : nuclear

使用搜索引擎搜索查询时，分页不起作用。该怎么办？

0 个答案: