MySQL / PHP搜索引擎 - 没有刷新? 提供的示例和文档

My question is rather lengthy, so I'll get right to it. I have a search engine set up that sends data (GET method) to a php script which queries a MySQL database and then displays the results. You can view the project, to get a better understanding, here: http://www.quinterest.org/testcategory/

The form consist of a search box as well as a multiple select option that narrow the search.

Everything thing works wonderfully, but there is one thing I would like to change and I don't know how. If someone could explain, in detail, what I need to do to be able to show the results (I figure it will be in a div written in the HTML?) from the query on the same page as the original form without the need to refresh the page?

If you would like an example, here is one: http://quizbowldb.com/search The search stays on the same page.

P.S. I know the mysql_ functions are outdated. Please don't harass me. I'm all very new to this still and the mysql_ functions are simple, easy and good enough for what I need. When I get further programming experience (I'm still in middle school), I may convert it to PDO or MySQLi.

HTML Form:

 <form action='search.php' method='GET' class="form-search">  
    <input type='text' placeholder="What would you like to learn about?" class="input-xxlarge search-query" id="inputInfo" name='search'><br></br>
    <input type='submit' class="btn btn-large btn-primary" name='submit' value='Search'></br>
    <select multiple="multiple" name='category[]'>
        <option value="%">All</option>
        <option>Literature</option>
        <option>History</option>
        <option>Science</option>
        <option>Fine Arts</option>
        <option>Trash</option>
        <option>Mythology</option>
        <option>Phylosophy</option>
        <option>Social Science</option>
        <option>Religion</option>
        <option>Geography</option>
    </select>
    </center>
</form>

search.php

<?php

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

print $search;



//validating search term length and connecting to db
if(strlen($search)<=1)
echo "Search term too short";
else{
echo "You searched for <b><em>$search</em></b> and ";
mysql_connect("fake","fake","fake");
mysql_select_db("quinterestdb");}


//validating search term for protection; if statement to avoid errors being displayed
if (strlen($search)>1){
mysql_real_escape_string($search);}


//exploding search with multiple words   
$search_exploded = explode (" ", $search); //creates array of all terms in search
foreach($search_exploded as $search_each) //loops through array
{
$x++;
if($x==1)
$construct .="Answer LIKE '%$search_each%'"; //if only one value in array
else
$construct .="AND Answer LIKE '%$search_each%'"; //for each multiple value in array




}
$cat = $_GET ['category']; //preparing array (multiple choices)
if (is_array($cat))
{
foreach($cat as $val) //
{
if($val=="%") //if no category is selected
continue;
else //split array choices (separated by ' and ,)
$comma_separated = implode("','", $cat);
$newvar = "AND Category IN('$comma_separated')"; //if category is chosen
}
} //ignore for now


$constructs ="SELECT * FROM tossupsdb WHERE $construct $newvar"; //completed search query





//quering the database; if statement to avoid errors being displayed
if (strlen($search)>1){
$run = mysql_query($constructs);}

print "$constructs"; //ignore for now



//number of results found; if statement to avoid errors being displayed
if (strlen($search)>1){
$foundnum = mysql_num_rows($run);}

if ($foundnum==0)
echo "Sorry, there are no matching result for <b>$search</b>.</br></br>1. 
Try more general words. for example: If you want to search 'how to create a website'
then use general keyword like 'create' 'website'</br>2. Try different words with similar
 meaning</br>3. Please check your spelling";
else
{   
echo " <span class='badge badge-info'> $foundnum </span>  results were found:<hr        size='5'>";

$per_page = 25; //preparing for pagination; results that appear per page
$start = $_POST['start']; //where to start results on page
$max_pages = ceil($foundnum / $per_page); //number of pages there will be
if(!$start) //starting at 0
$start=0; 
$getquery = mysql_query("SELECT * FROM tossupsdb WHERE $construct $newvar LIMIT $start,        $per_page");

while($runrows = mysql_fetch_array($getquery)) //fetching results
{
$answer = $runrows ['Answer']; //obtaining individual data from database
$category = $runrows ['Category']; //obtaining individual data from database
$num = $runrows ['Question #'];  //obtaining individual data from database
$difficulty = $runrows ['Difficulty'];  //obtaining individual data from database
$question = $runrows ['Question'];  //obtaining individual data from database
$round = $runrows ['Round'];  //obtaining individual data from database
$tournament = $runrows ['Tournament'];  //obtaining individual data from database
$year = $runrows ['Year'];  //obtaining individual data from database

//what will be displayed on the results page 
echo "<div class='alert alert-info' style='border-radius: 20px'><div style='padding:    10px'>
<span class='label label-info' font-size='30px'><em>Tournament | Year | Round | Question # | Category</em></span></div>
<b>$tournament |</b> <b>$year |</b> <b>$round |</b> <b>$num |</b> <b>$category</b>
<p><em>Question:</em> $question</p>
<div class='alert alert-info'><em><strong>ANSWER:</strong></em> $answer</div></div><hr>
";

}


    //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 class='btn btn-primary btn-large' href='search.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 == $start){
echo " <a class='btn' href='search.php?search=$search&submit=Search+source+code&start=$i'><b>$counter</b></a> ";
}
else {
echo " <a class='btn' href='search.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 == $start){
echo " <a class='btn' href='search.php?search=$search&submit=Search+source+code&start=$i'><b>$counter</b></a> ";
}
else {
echo " <a class='btn' href='search.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 class='btn' href='search.php?search=$search&submit=Search+source+code&start=0'>1</a> ";
echo " <a class='btn' href='search.php?search=$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 == $start){
echo " <a class='btn' href='search.php?search=$search&submit=Search+source+code&start=$i'><b>$counter</b></a> ";
}
else {
echo " <a class='btn' href='search.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 class='btn' href='search.php?search=$search&submit=Search+source+code&start=0'>1</a> ";
echo " <a class='btn' href='search.php?search=$search&submit=Search+source+code&start=$per_page'>2</a> .... ";

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

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

?>

You need to use AJAX to do that. Using AJAX, you send asynchronous requests (requests without loading the page) to the server.

This is how Google and other major search engines work. Learn about it here : Ajax tutorial

Ajax - Asynchronous JavaScript And XML

From Wikipedia definition of Ajax:

With Ajax, web applications can send data to, and retrieve data from, a server asynchronously (in the background) without interfering with the display and behavior of the existing page.

Data can be retrieved using the XMLHttpRequest object.

Despite the name, the use of XML is not required (JSON is often used instead), and the requests do not need to be asynchronous.

The simplest way to accomplish this is probably via jQuery, a JavaScript framework; by "simple", I mean the least work on your end:

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.1/jquery.min.js"></script>
<script>
    // This is the equivalent of the older $(document).ready() event
    $(function(){
        $('#search-form').on('submit', function(event){

            event.preventDefault(); // prevents form submission

            var data = $('#search-form').serialize();   // get all of the input variables in a neat little package
            var action = $('#search-form').attr('action');  // get the page to get/post to

            $.get(action, data, function(response, status, jqxhr){

                $('#target').html(response);

            });
        });
    });
</script>

Here, I add an id to your form so that I can directly target it. I also assume that there is a HTML element with an id of target that I can inject with the response HTML (which I also assume is only a fragment).