本文實(shí)例為大家分享了Openlayers實(shí)現(xiàn)圖形繪制的具體代碼,供大家參考,具體內(nèi)容如下
成都創(chuàng)新互聯(lián)-專業(yè)網(wǎng)站定制、快速模板網(wǎng)站建設(shè)、高性價(jià)比樂至網(wǎng)站開發(fā)、企業(yè)建站全套包干低至880元,成熟完善的模板庫,直接使用。一站式樂至網(wǎng)站制作公司更省心,省錢,快速模板網(wǎng)站建設(shè)找我們,業(yè)務(wù)覆蓋樂至地區(qū)。費(fèi)用合理售后完善,十年實(shí)體公司更值得信賴。1、新建一個(gè)html頁面,引入ol.js文件,然后在body中創(chuàng)建一個(gè)div標(biāo)簽、label標(biāo)簽和一個(gè)select下拉選項(xiàng)卡;
2、代碼實(shí)現(xiàn)
<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> <title></title> <script src="../lib/ol/ol.js"></script> <script type="text/javascript"> window.onload = function () { //獲取下拉列表框 var typeSelect = document.getElementById('type'); //定義一個(gè)用來接收繪制對(duì)象的對(duì)象,方便以后對(duì)繪制對(duì)象進(jìn)行添加、移除等操作 var draw; //初始化地圖對(duì)象 var map = new ol.Map({ target: 'map', layers: [ new ol.layer.Tile({ source: new ol.source.OSM() }) ], view: new ol.View({ center: [0, 0], zoom: 3 }) }); //初始化矢量數(shù)據(jù)源對(duì)象 //wrapX:Wrap the world horizontally. Default is true. //For vector editing across the -180° and 180° meridians to work properly, this should be set to false var source = new ol.source.Vector({ wrapX: false }); //實(shí)例化矢量數(shù)據(jù)圖層 var vector = new ol.layer.Vector({ //數(shù)據(jù)源 source: source, //樣式 style: new ol.style.Style({ //樣式填充 fill: new ol.style.Fill({ //填充顏色 color: 'rgba(37,241,239,0.2)' }), //筆觸 stroke: new ol.style.Stroke({ //筆觸顏色 color: '#264df6', //筆觸寬度 width:2 }), //圖形樣式,主要適用于點(diǎn)樣式 image: new ol.style.Circle({ //半徑大小 radius: 7, //填充 fill: new ol.style.Fill({ //填充顏色 color: '#e81818' }) }) }) }); //將矢量圖層加載到map中 map.addLayer(vector); //添加繪圖交互的函數(shù) function addInteraction() { //獲取當(dāng)前選擇的繪圖類型 var value = typeSelect.value; //如果當(dāng)前選擇的繪圖類型不為"None"的話,則進(jìn)行相應(yīng)繪圖操作 //如果當(dāng)前選擇的繪圖類型為"None"的話,則清空矢量數(shù)據(jù)源 if (value !== 'None') { //如果當(dāng)前的矢量數(shù)據(jù)源為空的話,則重新創(chuàng)建和設(shè)置數(shù)據(jù)源 //因?yàn)楫?dāng)你選擇的繪圖類型為"None"時(shí),會(huì)清空數(shù)據(jù)源 if (source == null) { source = new ol.source.Vector({ wrapX: false }); vector.setSource(source); } //geometryFunction變量,用來存儲(chǔ)繪制圖形時(shí)的回調(diào)函數(shù) //maxPoints變量,用來存儲(chǔ)大的點(diǎn)數(shù)量 var geometryFunction, maxPoints; //如果當(dāng)前選擇的繪圖類型是"Square"的話,則將value設(shè)置為Circle //然后調(diào)用createRegularPolygon()方法 if (value === 'Square') { value = 'Circle'; //Create a geometryFunction for type: 'Circle' //that will create a regular polygon with a user specified number of sides and start angle instead of an ol.geom. //根據(jù)圓來創(chuàng)建一個(gè)四邊形 geometryFunction = ol.interaction.Draw.createRegularPolygon(4); } else if (value === 'Rectangle') { //如果當(dāng)前選擇的繪圖類型是"Square"的話,則將value設(shè)置為L(zhǎng)ineString value = 'LineString'; //設(shè)置大點(diǎn)數(shù)為2 maxPoints = 2; geometryFunction = function (coordinates, geometry) { //如果geometry對(duì)象不存在或者為空,則創(chuàng)建 if (!geometry) { geometry = new ol.geom.Polygon(null); } //開始點(diǎn)的坐標(biāo) var start = coordinates[0]; //結(jié)束點(diǎn)的坐標(biāo) var end = coordinates[1]; //根據(jù)開始坐標(biāo)和結(jié)束坐標(biāo)設(shè)置繪圖點(diǎn)坐標(biāo) geometry.setCoordinates([ [start, [start[0], end[1]], end, [end[0], start[1]], start] ]); return geometry; }; } //將交互繪圖對(duì)象賦給draw對(duì)象 //初始化交互繪圖對(duì)象 draw = new ol.interaction.Draw({ //數(shù)據(jù)源 source: source, //繪制類型 type: value, //回調(diào)函數(shù) //Function that is called when a geometry's coordinates are updated geometryFunction: geometryFunction, //大點(diǎn)數(shù) maxPoints: maxPoints }); //將draw對(duì)象添加到map中,然后就可以進(jìn)行圖形繪制了 map.addInteraction(draw); } else { //清空矢量數(shù)據(jù)源 source = null; //設(shè)置矢量圖層的數(shù)據(jù)源為空 vector.setSource(source); } } //當(dāng)繪制類型下拉列表框的選項(xiàng)發(fā)生改變時(shí)執(zhí)行 typeSelect.onchange = function (e) { //從map中移除交互繪圖對(duì)象 //如果不移除,則會(huì)在下拉列表框選項(xiàng)發(fā)生改變時(shí)再次進(jìn)行繪制時(shí),保留上一次的draw對(duì)象 map.removeInteraction(draw); //執(zhí)行添加繪圖交互的函數(shù) addInteraction(); }; //添加繪圖交互的函數(shù) //此處是為保證刷新頁面后,仍然能夠根據(jù)下拉列表框框的選項(xiàng)進(jìn)行圖形繪制 addInteraction(); }; </script> </head> <body> <div id="menu"> <label>幾何圖形繪制:</label> <select id="type"> <option value="None">無</option> <option value="Point">點(diǎn)</option> <option value="LineString">線</option> <option value="Polygon">多邊形</option> <option value="Circle">圓</option> <option value="Square">正方形</option> <option value="Rectangle">長(zhǎng)方形</option> </select> </div> <div id="map"></div> </body> </html>
新聞標(biāo)題:Openlayers實(shí)現(xiàn)圖形繪制-創(chuàng)新互聯(lián)
網(wǎng)頁鏈接:http://muchs.cn/article10/cochgo.html
成都網(wǎng)站建設(shè)公司_創(chuàng)新互聯(lián),為您提供網(wǎng)站維護(hù)、網(wǎng)站排名、手機(jī)網(wǎng)站建設(shè)、全網(wǎng)營(yíng)銷推廣、網(wǎng)站設(shè)計(jì)公司、網(wǎng)站內(nèi)鏈
聲明:本網(wǎng)站發(fā)布的內(nèi)容(圖片、視頻和文字)以用戶投稿、用戶轉(zhuǎn)載內(nèi)容為主,如果涉及侵權(quán)請(qǐng)盡快告知,我們將會(huì)在第一時(shí)間刪除。文章觀點(diǎn)不代表本網(wǎng)站立場(chǎng),如需處理請(qǐng)聯(lián)系客服。電話:028-86922220;郵箱:631063699@qq.com。內(nèi)容未經(jīng)允許不得轉(zhuǎn)載,或轉(zhuǎn)載時(shí)需注明來源: 創(chuàng)新互聯(lián)
猜你還喜歡下面的內(nèi)容
營(yíng)銷型網(wǎng)站建設(shè)知識(shí)