php搜索与分页

Question

我得到未定义的索引：当我使用$start = $_GET['start'];

时从该行开始

<?php

$button = $_GET ['submit'];
$search = $_GET ['search']; 

echo "You searched for <b>$search</b> <hr size='1'></br>";
mysql_connect("localhost","root","");
mysql_select_db("page");

$search_exploded = explode (" ", $search);

foreach($search_exploded as $search_each)
{$x=0;
$construct="";
$x++;
if($x==1)
$construct .="name LIKE '%$search_each%'";
else
$construct .="AND name LIKE '%$search_each%'";

}

$constructs ="SELECT * FROM info WHERE $construct";
$run = mysql_query($constructs);

$foundnum = mysql_num_rows($run);

if ($foundnum==0)
echo "Sorry";
else
{ 

echo "$foundnum results found !<p>";
$per_page = 1;
$start = $_GET['start'];
$max_pages = ceil($foundnum / $per_page);
if(!$start)
$start=0; 
$getquery = mysql_query("SELECT * FROM info WHERE $construct LIMIT $start, $per_page");

while($runrows = mysql_fetch_assoc($getquery))
{
$id = $runrows ['id'];
$name = $runrows ['name'];
$email = $runrows ['email'];

echo " $id $name<br>";

}

//Pagination Starts
echo "<center>";

$prev = $start - $per_page;
$next = $start + $per_page;

$adjacents = 3;
$last = $max_pages - 1;

if($max_pages > 1)
{   
//previous button
if (!($start<=0)) 
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$prev'>Prev</a> ";    

//pages 
if ($max_pages < 7 + ($adjacents * 2))   //not enough pages to bother breaking it up
{
$i = 0;   
for ($counter = 1; $counter <= $max_pages; $counter++)
{
if ($i == $start){
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$i'><b>$counter</b></a> ";
}
else {
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$i'>$counter</a> ";
}  
$i = $i + $per_page;                 
}
}
elseif($max_pages > 5 + ($adjacents * 2))    //enough pages to hide some
{
//close to beginning; only hide later pages
if(($start/$per_page) < 1 + ($adjacents * 2))        
{
$i = 0;
for ($counter = 1; $counter < 4 + ($adjacents * 2); $counter++)
{
if ($i == $start){
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$i'><b>$counter</b></a> ";
}
else {
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$i'>$counter</a> ";
} 
$i = $i + $per_page;                                       
}

}
//in middle; hide some front and some back
elseif($max_pages - ($adjacents * 2) > ($start / $per_page) && ($start / $per_page) > ($adjacents * 2))
{
echo " <a href='index.php?search=$search&submit=Search+source+code&start=0'>1</a> ";
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$per_page'>2</a> .... ";

$i = $start;                 
for ($counter = ($start/$per_page)+1; $counter < ($start / $per_page) + $adjacents + 2; $counter++)
{
if ($i == $start){
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$i'><b>$counter</b></a> ";
}
else {
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$i'>$counter</a> ";
}   
$i = $i + $per_page;                
}

}
//close to end; only hide early pages
else
{
echo " <a href='index.php?search=$search&submit=Search+source+code&start=0'>1</a> ";
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$per_page'>2</a> .... ";

$i = $start;                
for ($counter = ($start / $per_page) + 1; $counter <= $max_pages; $counter++)
{
if ($i == $start){
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$i'><b>$counter</b></a> ";
}
else {
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$i'>$counter</a> ";   
} 
$i = $i + $per_page;              
}
}
}

//next button
if (!($start >=$foundnum-$per_page))
echo " <a href='index.php?search=$search&submit=Search+source+code&start=$next'>Next</a> ";    
}   
echo "</center>";
}  
?>

Answer 1

试试这个。

$start = (int) (!empty($_GET['start'])) ? $_GET['start'] : 0;