1.数据获取
画地图需要省份边界坐标，理论上可以每次都用百度API获取数据并绘图，但为了增加效率，首先将所有坐标都获取下来并存入数据库中。
新建省份数据数组
复制代码 代码如下:
var allZoneData = [{'name':'辽宁省','been':'yes','id':'01'},<span>{'name':'吉林省','been':'yes','id':'02'},……];</span>
轮询该数组，根据省份名称请求百度API获取坐标数据，并将数据以ajax方式放松给php
var myGeo = new BMap.Geocoder(); (function(){ for(var i = 0;i < allZoneData.length;i++){ getAllZone(allZoneData[i].name,allZoneData[i].been,allZoneData[i].id); } })(); //name为省份名，been表示是否去过，id为唯一标识，cir为省份圈号（有可能一个省份有两部分封闭圆圈构成） function getAllZone (name,been,id) { var data,temp; var bdary = new BMap.Boundary(); bdary.get(name, function(rs){ var count = rs.boundaries.length; for(var j = 0; j < count; j++){ var ply = new BMap.Polygon(rs.boundaries[j], {strokeWeight: 2, strokeColor: "#ff0000"}); data = ply.getPath(); $.ajax({ url: "addData.php", type:"POST", data: {'data':data,'name' : name,'cir':j,'been':been,'id':id}, success: function(txt){ console.log(txt); }, error: function(){ alert('添加数据出错！'); } }); } }); }
php得到数据后，解析数据并将数据存储到事先建好的数据库中
<?php header("content-type:text/html; charset=utf-8"); $data = $_REQUEST['data']; $name = $_REQUEST['name']; $cir = $_REQUEST['cir']; $been = $_REQUEST['been']; $id = $_REQUEST['id']; $con = mysql_connect("localhost","……","……"); if (!$con){ die('Could not connect: ' . mysql_error()); } mysql_select_db("……", $con); mysql_set_charset('utf8',$con); foreach ($data as $temp){ $sql = "insert into place (id,name,lng,lat,cir,been) values ('".$id."', '".$name."', '".$temp['lng']."','".$temp['lat']."','".$cir."','".$been."')"; if (!mysql_query($sql,$con)){ die('Error: ' . mysql_error()); } } mysql_close($con); echo 'Success'; ?>
2.画地图(base地图画在mapCanvas层)
轮询省份数组,并以ajax方式请求该省份边界坐标,然后绘图
var drawMap = function (context,data,l,t) { //context为绘制所在的层,l和t为相对位置,data为边界对象数组 if(data.been == 'yes'){ context.fillStyle = "green"; }else{ context.fillStyle = "grey"; } context.globalAlpha = 0.8; context.beginPath(); cleft = (data.coordinate[0].lng - temp_left) * bigger + l; //temp_left和temp_top为地图偏移位置. ctop = (temp_top - data.coordinate[0].lat) * bigger + t; //bigger为放大倍数 context.moveTo(cleft,ctop); for(var j = 1;j < data.coordinate.length;j++){ cleft = (data.coordinate[j].lng - temp_left) * bigger + l; ctop = (temp_top - data.coordinate[j].lat) * bigger + t; context.lineTo(cleft,ctop); } context.closePath(); context.stroke(); context.fill(); }
3.画移动连线(连线和移动的省份画在moveMapCanvas层)
当在地图上拖动省份时,出现若干条连接移动的省份和原省份的直线
var drawLinkLine = function(data,l,t){ //此处的l和t表示移动的相对位置 for(var k = 0;k < data.coordinate.length;k++){ if(k % 60 == 0){ moveMapContext.beginPath(); //根据移动距离的不同，设置连线的粗细 lineLength = Math.sqrt(l * l + t * t) / 100; lineLength = lineLength >= 4.5 ? 4.5 : lineLength; moveMapContext.lineWidth = 5 - lineLength; moveMapContext.strokeStyle = "rgba(0,120,60,0.4)"; cleft = (data.coordinate[k].lng - temp_left) * bigger; ctop = (temp_top - data.coordinate[k].lat) * bigger; moveMapContext.moveTo(cleft,ctop); cleft = (data.coordinate[k].lng - temp_left) * bigger + l; ctop = (temp_top - data.coordinate[k].lat) * bigger + t; moveMapContext.lineTo(cleft,ctop); moveMapContext.closePath(); moveMapontext.stroke(); } } }
4.事件
鼠标按下事件:当点击到地图上时,要做的事是,判断点击位置,将位置信息转化成经纬度,再通过百度API根据经纬度获得省份名称。
$('#eventCanvas').mousedown(function(ev){ //获取点击canvas的坐标 var mouseX, mouseY; if(ev.layerX || ev.layerX==0){ mouseX = ev.layerX; mouseY = ev.layerY; }else if(ev.offsetX || ev.offsetX==0){ mouseX = ev.offsetX; mouseY = ev.offsetY; } //保存点击时的原坐标值 tempX = mouseX; tempY = mouseY; //将坐标转化为经纬度 mouseX = mouseX/bigger + temp_left; mouseY = temp_top - mouseY/bigger; if(opts.dragAll){ draging = true; }else{ moveMapContext.clearRect(0, 0, 1100, 630); //根据经纬度获得所在地理位置并获取边界坐标再画线 myGeo.getLocation(new BMap.Point(mouseX, mouseY), function(result){ tempName = ''; draging = true; name = result.addressComponents.province; tempName = name; pubFuns.drawMoveLayerLine(0,0); }); } });
鼠标移动事件：根据点击的省份名，获得数据，并实时重绘移动层的省份