所属分类:web前端开发
随着互联网技术的发展,Web地图已经成为了数据展示与交互的重要工具。在Web地图中,常见的功能之一就是地图矩形编辑。用户可以通过拖动地图上的矩形,来选择自己感兴趣的区域。本文将介绍如何利用JavaScript和腾讯地图实现地图矩形编辑功能,并提供具体的代码示例。
一、前置条件
在开始编写代码之前,我们需要准备好以下条件:
二、创建地图并添加工具栏
在HTML文件中创建一个容器,用于显示地图。然后写入一些JavaScript代码,创建地图,并添加一个工具栏。
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>地图矩形编辑示例</title> <style type="text/css"> #map-container { width: 100%; height: 600px; } </style> </head> <body> <div id="map-container"></div> <script type="text/javascript" src="https://map.qq.com/api/js?v=2.exp&key=YOUR_KEY_HERE"></script> <script type="text/javascript"> var map = new qq.maps.Map(document.getElementById('map-container'), { center: new qq.maps.LatLng(39.916527, 116.397128), zoom: 10 }); //添加矩形工具栏 var toolBar = new qq.maps.DrawingTools({ map: map, drawingMode: qq.maps.DrawingTool.RECTANGLE, rectangleOptions: { fillColor: qq.maps.Color.fromHex('#FF6600', 0.4), strokeColor: qq.maps.Color.fromHex('#FF6600'), strokeWidth: 2 } }); </script> </body> </html>
代码解释:
三、捕获矩形绘制事件
现在,我们已经成功地添加了一个矩形工具栏。但是,我们需要做的是捕获用户绘制矩形的事件,并在控制台上输出矩形的边框坐标。
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>地图矩形编辑示例</title> <style type="text/css"> #map-container { width: 100%; height: 600px; } </style> </head> <body> <div id="map-container"></div> <script type="text/javascript" src="https://map.qq.com/api/js?v=2.exp&key=YOUR_KEY_HERE"></script> <script type="text/javascript"> var map = new qq.maps.Map(document.getElementById('map-container'), { center: new qq.maps.LatLng(39.916527, 116.397128), zoom: 10 }); //添加矩形工具栏 var toolBar = new qq.maps.DrawingTools({ map: map, drawingMode: qq.maps.DrawingTool.RECTANGLE, rectangleOptions: { fillColor: qq.maps.Color.fromHex('#FF6600', 0.4), strokeColor: qq.maps.Color.fromHex('#FF6600'), strokeWidth: 2 } }); //捕获矩形绘制事件 qq.maps.event.addListener(toolBar, 'rectanglecomplete', function(event) { var bounds = event.getBounds(); console.log('矩形边框左上角坐标:' + bounds.getNorthEast().toString() + ' 矩形边框右下角坐标:' + bounds.getSouthWest().toString()); }); </script> </body> </html>
代码解释:
qq.maps.event.addListener()
函数来捕获矩形绘制事件;四、绘制矩形
最后一个步骤是,在地图上绘制矩形。我们需要创建一个函数,将矩形的边框坐标作为参数传递进去。在该函数中,我们可以使用qq.maps.Polygon
类创建一个多边形,并添加到地图上。
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>地图矩形编辑示例</title> <style type="text/css"> #map-container { width: 100%; height: 600px; } </style> </head> <body> <div id="map-container"></div> <script type="text/javascript" src="https://map.qq.com/api/js?v=2.exp&key=YOUR_KEY_HERE"></script> <script type="text/javascript"> var map = new qq.maps.Map(document.getElementById('map-container'), { center: new qq.maps.LatLng(39.916527, 116.397128), zoom: 10 }); var polygons = []; //添加矩形工具栏 var toolBar = new qq.maps.DrawingTools({ map: map, drawingMode: qq.maps.DrawingTool.RECTANGLE, rectangleOptions: { fillColor: qq.maps.Color.fromHex('#FF6600', 0.4), strokeColor: qq.maps.Color.fromHex('#FF6600'), strokeWidth: 2 } }); //捕获矩形绘制事件 qq.maps.event.addListener(toolBar, 'rectanglecomplete', function(event) { var bounds = event.getBounds(); //绘制矩形 var polygon = new qq.maps.Polygon({ map: map, path: [ new qq.maps.LatLng(bounds.getNorthEast().getLat(), bounds.getSouthWest().getLng()), new qq.maps.LatLng(bounds.getNorthEast().getLat(), bounds.getNorthEast().getLng()), new qq.maps.LatLng(bounds.getSouthWest().getLat(), bounds.getNorthEast().getLng()), new qq.maps.LatLng(bounds.getSouthWest().getLat(), bounds.getSouthWest().getLng()) ], fillColor: qq.maps.Color.fromHex('#FF6600', 0.4), strokeColor: qq.maps.Color.fromHex('#FF6600'), strokeWidth: 2 }); polygons.push(polygon); }); </script> </body> </html>
代码解释:
到此为止,我们已经成功地实现了地图矩形编辑功能。用户可以通过拖动地图上的矩形,选择自己感兴趣的区域,并在地图上绘制矩形。具体代码示例请参见以下完整示例:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>地图矩形编辑示例</title> <style type="text/css"> #map-container { width: 100%; height: 600px; } </style> </head> <body> <div id="map-container"></div> <script type="text/javascript" src="https://map.qq.com/api/js?v=2.exp&key=YOUR_KEY_HERE"></script> <script type="text/javascript"> var map = new qq.maps.Map(document.getElementById('map-container'), { center: new qq.maps.LatLng(39.916527, 116.397128), zoom: 10 }); var polygons = []; //添加矩形工具栏 var toolBar = new qq.maps.DrawingTools({ map: map, drawingMode: qq.maps.DrawingTool.RECTANGLE, rectangleOptions: { fillColor: qq.maps.Color.fromHex('#FF6600', 0.4), strokeColor: qq.maps.Color.fromHex('#FF6600'), strokeWidth: 2 } }); //捕获矩形绘制事件 qq.maps.event.addListener(toolBar, 'rectanglecomplete', function(event) { var bounds = event.getBounds(); //绘制矩形 var polygon = new qq.maps.Polygon({ map: map, path: [ new qq.maps.LatLng(bounds.getNorthEast().getLat(), bounds.getSouthWest().getLng()), new qq.maps.LatLng(bounds.getNorthEast().getLat(), bounds.getNorthEast().getLng()), new qq.maps.LatLng(bounds.getSouthWest().getLat(), bounds.getNorthEast().getLng()), new qq.maps.LatLng(bounds.getSouthWest().getLat(), bounds.getSouthWest().getLng()) ], fillColor: qq.maps.Color.fromHex('#FF6600', 0.4), strokeColor: qq.maps.Color.fromHex('#FF6600'), strokeWidth: 2 }); polygons.push(polygon); }); </script> </body> </html>