I have used this tutorial from Google to build a web app that finds the closest store from the user entered location:

http://code.google.com/apis/maps/articles/phpsqlsearch_v3.html

I have my app almost working the way I want it, upon page load, the map is loaded, centered and set to zoom level 6 and the user fills out the form with their location.

The app then pulls all the store info from the db and populates the map with a marker for each.

The zoom level seems to decrease aswell but I can't find this in the code anywhere.

What I actually want to do on submit is zoom in to zoom level 6 and center the map to the latitude and longitude of the user entered location and output info on the nearest stores, e.g the nearest 5. I was wondering if anyone here knew how to implement this feature?

index.php

<div>

    <input type=text id=addressInput size=50/>

    <input type=hidden id=radiusSelect value=5/>

    <input type=button onclick=searchLocations() value=Search/>

</div>

<div><select id=locationSelect style=width:100%;visibility:hidden></select></div>

<div id=map style=width:100%; height:50%></div>







<script type=text/javascript src=https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js></script>

<script src=http://maps.google.com/maps/api/js?sensor=false type=text/javascript></script>

<script type=text/javascript>

//<![CDATA[

var map;

var markers = [];

var infoWindow;

var locationSelect;



function load() {

  map = new google.maps.Map(document.getElementById(map), {

    center: new google.maps.LatLng(54.600939134593, -2.399894114594),

    zoom: 6,

    mapTypeId: 'roadmap',

    mapTypeControlOptions: {style: google.maps.MapTypeControlStyle.DROPDOWN_MENU}

  });

  infoWindow = new google.maps.InfoWindow();



  locationSelect = document.getElementById(locationSelect);

  locationSelect.onchange = function() {

    var markerNum = locationSelect.options[locationSelect.selectedIndex].value;

    if (markerNum != none){

      google.maps.event.trigger(markers[markerNum], 'click');

    }

  };

}



function searchLocations() {

 var address = document.getElementById(addressInput).value;

 var geocoder = new google.maps.Geocoder();

 geocoder.geocode({address: address}, function(results, status) {

   if (status == google.maps.GeocoderStatus.OK) {

    searchLocationsNear(results[0].geometry.location);

   } else {

     alert(address + ' not found');

   }

 });

}



function clearLocations() {

 infoWindow.close();

 for (var i = 0; i < markers.length; i++) {

   markers[i].setMap(null);

 }

 markers.length = 0;



 locationSelect.innerHTML = ;

 var option = document.createElement(option);

 option.value = none;

 option.innerHTML = See all results:;

 locationSelect.appendChild(option);

}



function searchLocationsNear(center) {

 clearLocations(); 



 var radius = document.getElementById('radiusSelect').value;

 var searchUrl = 'phpsqlsearch_genxml.php?lat=' + center.lat() + '&lng=' + center.lng() + '&radius=' + radius;

 downloadUrl(searchUrl, function(data) {

   var xml = parseXml(data);

   var markerNodes = xml.documentElement.getElementsByTagName(marker);

   var bounds = new google.maps.LatLngBounds();

   for (var i = 0; i < markerNodes.length; i++) {

     var town = markerNodes[i].getAttribute(town);

     var postcode = markerNodes[i].getAttribute(postcode);

     var name = markerNodes[i].getAttribute(name);

     var address = markerNodes[i].getAttribute(address);

     var distance = parseFloat(markerNodes[i].getAttribute(distance));

     var latlng = new google.maps.LatLng(

          parseFloat(markerNodes[i].getAttribute(lat)),

          parseFloat(markerNodes[i].getAttribute(lng)));



    var id = markerNodes[i].getAttribute(id);

    var fname = markerNodes[i].getAttribute(fname);

    var link = '<a href=http://www.domain.co.uk/stores/' + fname + '-' + id + '.html target=_blank title=Store: ' + town + '>More info</a>';



     createOption(name, distance, i);

     createMarker(latlng, name, address, town, postcode, link);

     bounds.extend(latlng);

   }

   map.fitBounds(bounds);

   locationSelect.style.visibility = visible;

   locationSelect.onchange = function() {

     var markerNum = locationSelect.options[locationSelect.selectedIndex].value;

     google.maps.event.trigger(markers[markerNum], 'click');

   };

  });

 }



 function createMarker(latlng, name, address, town, postcode, link) {

  var html = <b> + town + </b> <br/> + address + <br/> + postcode + <br/> + link;

  var marker = new google.maps.Marker({

    map: map,

    position: latlng

  });

  google.maps.event.addListener(marker, 'click', function() {

    infoWindow.setContent(html);

    infoWindow.open(map, marker);

  });

  markers.push(marker);

}



 function createOption(name, distance, num) {

  var option = document.createElement(option);

  option.value = num;

  option.innerHTML = name + ( + distance.toFixed(1) + );

  locationSelect.appendChild(option);

 }



 function downloadUrl(url, callback) {

  var request = window.ActiveXObject ?

      new ActiveXObject('Microsoft.XMLHTTP') :

      new XMLHttpRequest;



  request.onreadystatechange = function() {

    if (request.readyState == 4) {

      request.onreadystatechange = doNothing;

      callback(request.responseText, request.status);

    }

  };



  request.open('GET', url, true);

  request.send(null);

 }



 function parseXml(str) {

  if (window.ActiveXObject) {

    var doc = new ActiveXObject('Microsoft.XMLDOM');

    doc.loadXML(str);

    return doc;

  } else if (window.DOMParser) {

    return (new DOMParser).parseFromString(str, 'text/xml');

  }

 }



 function doNothing() {}



//]]>

</script>





<script type=text/javascript>

    $(document).ready(function() {

        load();

    });

</script>

phpsqlsearch_genxml.php

<?php

$db_conn = mysql_connect('xxx.xxx.xx.xx', 'xxxxxxxx', 'xxxxxx') or die('error');

mysql_select_db('uk_db', $db_conn) or die(mysql_error());



// Get parameters from URL

$center_lat = $_GET[lat];

$center_lng = $_GET[lng];

$radius = $_GET[radius];



if(!$_GET['zoom']) { 

    $_GET['zoom'] = 11; 

}



// Start XML file, create parent node

$dom = new DOMDocument(1.0);

$node = $dom->createElement(markers);

$parnode = $dom->appendChild($node);





// Select all the rows in the markers table

$query = 'SELECT address1, address2, address3, longitude, latitude, name, town, store_id, postcode, storenumber 

          FROM uk_store

          WHERE isActive=1 ';

if($_GET[region] != '') {

    $query .= ' AND region = ' . $_GET[region] . '';

} else {

    $query .= ' AND region in(Scotland, England, Wales, Northern Ireland) ';

}



// lets start to check what has been search on

if($_GET['postcode'] != '') {



  //lets make sure postcode only has numbers letter and spaces

  $searchparams .= 'postcode=' . $_GET['postcode'] . '&amp;';

  $postcode = $_GET['postcode'];

  $postcode = verifyInput($postcode);

  $query .=  AND postcode = ' . $postcode . ';



}



if($_GET['town'] != '') {

    // make sure town only has letters or spaces.

    $searchparams .= 'town=' . $_GET['town'] . '&amp;';

    $town = $_GET['town']; 

    $town = verifyInput($town);

    $query .=  AND town = ' . $town . ';

}



if($_GET['min_lat'] && $_GET['min_long'] && $_GET['max_lat'] && $_GET['max_long'] ) {

   $query .=    AND latitude BETWEEN  . $_GET['min_lat'] .  AND  . $_GET['max_lat'] .  AND longitude BETWEEN  . $_GET['min_long'] .  AND  . $_GET['max_long'] ;

   $mapsearch = 1;

}



if(!($_GET['postcodeLat'] && $_GET['postcodeLong'])) {

    $query .=  ORDER BY Region, Town , Name ; 

}



$result = mysql_query($query);

if (!$result) {

  die(Invalid query:  . mysql_error());

}



header(Content-type: text/xml);



echo '<markers>';



if($_GET['postcodeLat'] && $_GET['postcodeLong'])

{

    $count = 0;



   // we need to sort the results by distance

    while ($row = @mysql_fetch_array($result, MYSQL_ASSOC))

    {

        $address = $row['address1'] . ' ' . $row['address2'] . ' ' . $row['address3'];

        $distance = distance($_GET['postcodeLat'], $_GET['postcodeLong'], $row['latitude'], $row['longitude']); 

        $row['distance'] = number_format($distance, 2);

        $row['fname'] = $row['town'] . '-' . $row['name'];

        $row['fname'] = str_replace(','', $row['fname']);

        $row['fname'] = ereg_replace(' ','-', $row['fname']); 

        $row['fname'] = ereg_replace('/','-', $row['fname']);

        $row['fname'] = ereg_replace('(','', $row['fname']);

        $row['fname'] = ereg_replace(')','', $row['fname']);

        $row['fname'] = strtolower($row['fname']);

        //get distance and add to $row array

        $results[$distance.$row['id']] = $row;        

    } 



    ksort($results);



    foreach ($results as $key => $row) 

    {

      // ADD TO XML DOCUMENT NODE 

        $address = $row['address1'] . ' ' . $row['address2'] . ' ' . $row['address3'];  

        echo '<marker ';  

        echo 'name=' . parseToXML($row['name']) . ' ';  

        echo 'fname=' . parseToXML($row['fname']) . ' '; 

        echo 'town=' . parseToXML($row['town']) . ' ';  

        echo 'lat=' . $row['latitude'] . ' ';  

        echo 'lng=' . $row['longitude'] . ' ';  

        echo 'id=' . $row['store_id'] . ' ';  

        echo 'address=' . $address . ' '; 

        echo 'distance=' . $row['distance'] . ' '; 

        echo 'postcode=' . $row['postcode'] . ' ';

        echo 'storenumber=' . $row['storenumber'] . ' ';

        echo 'address1=' . parsetoXml($row['address1']). ' '; 

        echo 'address2=' . parsetoXml($row['address2']). ' '; 

        echo 'address3=' . parsetoXml($row['address3']). ' ';

        echo '/>';

    }



}

else

{

    // Iterate through the rows, printing XML nodes for each

    while ($row = @mysql_fetch_assoc($result))

    {

         $address = $row['address1'] . ' ' . $row['address2'] . ' ' . $row['address3'];

         $row['fname'] = $row['town'] . '-' . $row['name'];

         $row['fname'] = ereg_replace(' ','-', $row['fname']); 

         $row['fname'] = ereg_replace('/','-', $row['fname']);

         $row['fname'] = ereg_replace('(','', $row['fname']);

         $row['fname'] = ereg_replace(')','', $row['fname']);



        // ADD TO XML DOCUMENT NODE  

        echo '<marker ';  

        echo 'name=' . parseToXML($row['name']) . ' ';

        echo 'fname=' . strtolower(parseToXML($row['fname'])) . ' '; 

        echo 'town=' . parseToXML($row['town']) . ' ';  

        echo 'lat=' . $row['latitude'] . ' ';  

        echo 'lng=' . $row['longitude'] . ' ';  

        echo 'id=' . $row['store_id'] . ' ';  

        echo 'isSurg=' . $row['isLaserSurgery'] . ' '; 

        echo 'isCons=' . $row['isLaserConsult'] . ' '; 

        echo 'address=' . parsetoXml($address). ' '; 

        echo 'address1=' . parsetoXml($row['address1']). ' '; 

        echo 'address2=' . parsetoXml($row['address2']). ' '; 

        echo 'address3=' . parsetoXml($row['address3']). ' '; 

        echo 'postcode=' . $row['postcode'] . ' '; 

        echo 'storenumber=' . $row['storenumber'] . ' ';

        echo '/>';

    }

}

// End XML file

echo '</markers>';





// make sure the data is xml friendly

function parseToXML($htmlStr) 

{ 

    $xmlStr=str_replace('<','&lt;',$htmlStr); 

    $xmlStr=str_replace('>','&gt;',$xmlStr); 

    $xmlStr=str_replace('','&quot;',$xmlStr); 

    //$xmlStr=str_replace(','&#39;',$xmlStr); 

    $xmlStr=str_replace(&,'&amp;',$xmlStr); 

    return $xmlStr; 

}



// calculate the distance in miles or kms between any two points 

function distance($lat1, $lon1, $lat2, $lon2, $unit = '') { 

    $theta = $lon1 - $lon2; 

    $dist = sin(deg2rad($lat1)) * sin(deg2rad($lat2)) +  cos(deg2rad($lat1)) * cos(deg2rad($lat2)) * cos(deg2rad($theta)); 

    $dist = acos($dist); 

    $dist = rad2deg($dist); 

    $miles = $dist * 60 * 1.1515;

    if($unit != '')

    {

        $unit = strtoupper($unit);

    }



if ($unit == K) {

    return ($miles * 1.609344); 

} else if ($unit == N) {

  return ($miles * 0.8684);

} else {

    return $miles;

  }

} 



function VerifyInput ($input, $forceInt = false) { 



if (is_numeric($input)) { 

    return $input; 

} elseif (!$forceInt) { 



    if (get_magic_quotes_gpc() && trim(ini_get(magic_quotes_sybase)) == ) { 

        $input = stripslashes($input); 

        $input = str_replace(', , $input); 

        $input = str_replace(`, , $input);

    } elseif (!get_magic_quotes_gpc()) { 

        $input = str_replace(', , $input);

        $input = str_replace(`, , $input); 

    } 

    return $input; 

} elseif ($forceInt) { 

    return 0; 

} 

} 



?>

Apologies, that's a lot of pasting there but I thought it better to include everything rather than risk someone not being able to answer because there wasn't enough detail.

UPDATE

I have tried inserting this piece of code into the searchLocations function but it doesn't seem tochange the behaviour in anyway:

function searchLocations() {

 var address = document.getElementById(addressInput).value;

 var geocoder = new google.maps.Geocoder();

 geocoder.geocode({address: address}, function(results, status) {

   if (status == google.maps.GeocoderStatus.OK) {

    searchLocationsNear(results[0].geometry.location);

    /////////////// new code

    var myOptions = {

    zoom: 11,

    center: address.geometry.location,

    mapTypeId: google.maps.MapTypeId.TERRAIN

    }

    map = new google.maps.Map(document.getElementById(map), myOptions);

    ////////////////



   } else {

     alert(address + ' not found');

   }

 });

}