Google Maps API v3：如何设置缩放级别和地图中心到用户提交的位置？

Question

我已经使用Google的这个教程来构建一个Web应用程序，该应用程序从用户输入的位置找到最近的商店：

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

我的应用程序几乎按照我想要的方式工作，在页面加载时，地图被加载，居中并设置为缩放级别6，用户用他们的位置填写表单。

该应用程序然后从数据库中提取所有商店信息，并使用每个标记填充地图。

缩放级别似乎也在减少，但我无法在任何地方的代码中找到它。

我实际想要提交的内容是放大到缩放级别6并将地图中心放在用户输入的位置的纬度和经度以及最近的商店的输出信息，例如最近的5.我想知道是否有人这里知道如何实现这个功能吗？

的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; 
} 
} 

?>

道歉，那里有很多粘贴，但我认为最好包括所有内容，而不是因为没有足够的细节而冒着某人无法回答的风险。

更新

我尝试将这段代码插入到searchLocations函数中，但似乎无论如何都不会改变行为：

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');
   }
 });
}

Answer 1

找到我在文档中寻找的方法（惊喜，惊喜！）

只需在map.fitBounds(bounds);函数的searchLocationsNear下添加这两行：

   map.setZoom(11);
   map.setCenter(center);

Answer 2

既然你说这会被用作Facebook应用程序，我有一个友好的建议。

现在您的代码正在运行，您应该考虑将其包装在自己的命名空间中并实现module pattern。这样做可以保证您的函数名称，尤其是load（）不会在同一FB页面上发生冲突或被其他应用程序覆盖。

我创建了一个小sample app here。你的可能就像这样简单：

if (!window.Carlin) { window.Carling = {}; }
Carlin.Locator = function() {

    var map,markers,infoWindow,locationSelect;

    markers = [];

    function load() {
    }

    function searchLocations() {
    }

    function clearLocations() {
    }

    //...etc

    return {
        init: load
    }
}();

$(document).ready(Carlin.Locator.init);