代码如下（测距、测面和清除）
import Draw from 'ol/interaction/Draw'
import VectorSource from 'ol/source/Vector';
import VectorLayer from 'ol/layer/Vector';
import Point from "ol/geom/Point";
import {
unByKey
} from 'ol/Observable.js';
import Overlay from 'ol/Overlay';
import {Feature } from "ol";
import {getLength} from 'ol/sphere';
import {getArea} from 'ol/sphere';
import LineString from 'ol/geom/LineString';
import Polygon from 'ol/geom/Polygon';
import {
Circle as CircleStyle,
Fill,
Stroke,
Style
} from 'ol/style.js';
// 测距所需对象
var lineVectorLayer = null;
var lineDraw = null;
// 测面所需对象
var areaVectorLayer = null;
var areaDraw = null;
// 测距
export const measureLineMethod = (map) => {
clearMeasures(map);//清空测量图层
// 创建数据源
var source = new VectorSource();
lineVectorLayer = new VectorLayer({
id:'Line',
source: source,
style: new Style({
fill: new Fill({
color: 'rgba(255, 255, 255, 0.2)'
}),
stroke: new Stroke({
color: 'red',
width: 2
}),
image: new CircleStyle({
radius: 7,
fill: new Fill({
color: '#ffcc33'
})
})
}),
zIndex:16
});
map.addLayer(lineVectorLayer)
/**
* Currently drawn feature.
* @type {module:ol/Feature~Feature}
*/
var sketch;
/** 测距
* The help tooltip element.
* @type {Element}
*/
var lineHelpTooltipElement;
/**
* Overlay to show the help messages.
* @type {module:ol/Overlay}
*/
var lineHelpTooltip;
/**
* The measure tooltip element.
* @type {Element}
*/
var measureTooltipElement;
/**
* Overlay to show the measurement.
* @type {module:ol/Overlay}
*/
var measureTooltip;
/**
* Message to show when the user is drawing a line.
* @type {string}
*/
var continueLineMsg = '';
createMeasureTooltip();
createHelpTooltip();
/**
* Handle pointer move.
* @param {module:ol/MapBrowserEvent~MapBrowserEvent} evt The event.
*/
var pointerMoveHandler = function (evt) {
if (evt.dragging) {
return;
}
/** @type {string} */
var helpMsg = '请点击开始测距';
if (sketch) {
// 测量时的提示文字
var geom = (sketch.getGeometry());
if (geom instanceof LineString) {
helpMsg = continueLineMsg;
}
}
// 设置提示对话框
//lineHelpTooltipElement.innerHTML = helpMsg;// 文字没有颜色
lineHelpTooltipElement.innerHTML = "<span style='color: red;'>"+helpMsg+"</span>";
lineHelpTooltip.setPosition(evt.coordinate);
lineHelpTooltipElement.classList.remove('hidden');
};
// 监听鼠标移动方法
map.on('pointermove', pointerMoveHandler);
map.getViewport().addEventListener('mouseout', function () {
lineHelpTooltipElement.classList.add('hidden');
});
var draw;// 绘制对象
var formatLength = function (line) {
//获取投影坐标系
var sourceProj = map.getView().getProjection();
//ol/sphere里有getLength()和getArea()用来测量距离和区域面积，默认的投影坐标系是EPSG:3857, 其中有个options的参数，可以设置投影坐标系
var length = getLength(line, {projection: sourceProj});
//var length = getLength(line);
var output;
if (length > 100) {
output = (Math.round(length / 1000 * 100) / 100) +
' ' + 'km';
} else {
output = (Math.round(length * 100) / 100) +
' ' + 'm';
}
return output;
};
// 获取存放feature的vectorlayer层。map初始化的时候可以添加好了
for(let layerTmp of map.getLayers().getArray()){
if(layerTmp.get("name")=="feature"){
source = layerTmp.getSource();
}
}
// 测量距离
function addLineInteraction() {
var type = "LineString";
draw = new Draw({
source: source,
type: type,
style: new Style({
fill: new Fill({
color: 'rgba(255, 255, 255, 0.2)'
}),
stroke: new Stroke({
color: 'rgba(0, 200, 255, 0.5)',
lineDash: [10, 10],
width: 2
}),
image: new CircleStyle({
radius: 5,
stroke: new Stroke({
color: 'rgba(0, 200, 255, 0.7)'
}),
fill: new Fill({
color: 'rgba(255, 255, 255, 0.2)'
})
})
})
});
// 赋值
lineDraw = draw;
map.addInteraction(lineDraw);
var listener;
draw.on('drawstart',
function (evt) {
// set sketch
sketch = evt.feature;
/** @type {module:ol/coordinate~Coordinate|undefined} */
var tooltipCoord = evt.coordinate;
listener = sketch.getGeometry().on('change', function (evt) {
var geom = evt.target;
var output;
if (geom instanceof LineString) {
output = formatLength(geom);
tooltipCoord = geom.getLastCoordinate();
}
//measureTooltipElement.innerHTML = output;// 文字没有颜色
measureTooltipElement.innerHTML = "<span style='color: red;'>"+output+"</span>";
measureTooltip.setPosition(tooltipCoord);
});
/* //地图双击事件-点位不准确
map.on('dblclick', function (evt) {
// 添加点
var point = new Point(evt.coordinate);
source.addFeature(new Feature(point));
}); */
}, this);
draw.on('drawend',
function (evt) {
//measureTooltipElement.className = 'tooltip tooltip-static';
measureTooltip.setOffset([0, -7]);
// unset sketch
sketch = null;
// unset tooltip so that a new one can be created
measureTooltipElement = null;
createMeasureTooltip();
unByKey(listener);
map.un('pointermove', pointerMoveHandler);
map.removeInteraction(draw);
lineHelpTooltipElement.classList.add('hidden');
// 下面代码在绘制结束后添加点（线的最后一个坐标点）
// 获取properties
//var properties = evt.feature.getProperties();
//console.log("properties",JSON.stringify(properties));
// 获取geometry
var geometry = evt.feature.getGeometry();
// 获取坐标点集合
var corrdinates = geometry.getCoordinates();
//console.log("corrdinates",corrdinates);
// 创建线
var lineString = new LineString(corrdinates);
// 获取线段最后的点坐标
//console.log("lineString.getLastCoordinate()",lineString.getLastCoordinate());
var point = new Point(lineString.getLastCoordinate());
source.addFeature(new Feature(point));
}, this);
}
function createHelpTooltip() {
if (lineHelpTooltipElement) {
lineHelpTooltipElement.parentNode.removeChild(lineHelpTooltipElement);
}
lineHelpTooltipElement = document.createElement('div');
//lineHelpTooltipElement.className = 'tooltip hidden';
lineHelpTooltip = new Overlay({
element:lineHelpTooltipElement,
offset: [15, 0],
positioning: 'center-left',
});
map.addOverlay(lineHelpTooltip);
}
function createMeasureTooltip() {
if (measureTooltipElement) {
measureTooltipElement.parentNode.removeChild(measureTooltipElement);
}
measureTooltipElement = document.createElement('div');
//measureTooltipElement.className = 'tooltip tooltip-measure';
measureTooltip = new Overlay({
element: measureTooltipElement,
offset: [0, -15],
positioning: 'bottom-center'
});
map.addOverlay(measureTooltip);
}
// 量测调用
addLineInteraction();
}
// 测面
export const measurePolygonMethod = (map) =>{
clearMeasures(map);//清空测量图层
// 创建数据源
var source = new VectorSource();
areaVectorLayer = new VectorLayer({
id:'Area',
source: source,
style: new Style({
fill: new Fill({
color: 'rgba(255, 255, 255, 0.2)'
}),
stroke: new Stroke({
color: 'red',
width: 2
}),
image: new CircleStyle({
radius: 7,
fill: new Fill({
color: '#ffcc33'
})
})
}),
zIndex:16
});
map.addLayer(areaVectorLayer);
/**
* Currently drawn feature.
* @type {module:ol/Feature~Feature}
*/
var sketch;
/**
* The help tooltip element.
* @type {Element}
*/
var areaHelpTooltipElement;
/**
* Overlay to show the help messages.
* @type {module:ol/Overlay}
*/
var areaHelpTooltip;
/**
* The measure tooltip element.
* @type {Element}
*/
var measureTooltipElement;
/**
* Overlay to show the measurement.
* @type {module:ol/Overlay}
*/
var measureTooltip;
/**
* Message to show when the user is drawing a polygon.
* @type {string}
*/
var continuePolygonMsg = '';
createMeasureTooltip();
createHelpTooltip();
/**
* Handle pointer move.
* @param {module:ol/MapBrowserEvent~MapBrowserEvent} evt The event.
*/
var pointerMoveHandler = function (evt) {
if (evt.dragging) {
return;
}
/** @type {string} */
var helpMsg = '请点击开始测面';
if (sketch) {
var geom = (sketch.getGeometry());
if (geom instanceof Polygon) {
helpMsg = continuePolygonMsg;
}
}
//areaHelpTooltipElement.innerHTML = helpMsg;//没有颜色
areaHelpTooltipElement.innerHTML = "<span style='color: red;'>"+helpMsg+"</span>";
areaHelpTooltip.setPosition(evt.coordinate);
areaHelpTooltipElement.classList.remove('hidden');
};
// 监听鼠标移动方法
map.on('pointermove', pointerMoveHandler);
map.getViewport().addEventListener('mouseout', function () {
areaHelpTooltipElement.classList.add('hidden');
});
var draw;
var formatArea = function (polygon) {
//获取投影坐标系
var sourceProj = map.getView().getProjection();
var area = getArea(polygon, {projection: sourceProj})
//var area = getArea(polygon);
//console.info(area)
var output;
if (area > 10000) {
output = (Math.round(area / 1000000 * 100) / 100) +
' ' + 'km<sup>2</sup>';
} else {
output = (Math.round(area * 100) / 100) +
' ' + 'm<sup>2</sup>';
}
return output;
};
// 获取存放feature的vectorlayer层。map初始化的时候可以添加好了
for(let layerTmp of map.getLayers().getArray()){
if(layerTmp.get("name")=="feature"){
// layer = layerTmp;
// layerTmp.setSource(null)
source = layerTmp.getSource();
}
}
// 测量面
function addAreaInteraction() {
var type = "Polygon";
draw = new Draw({
source: source,
type: type,
style: new Style({
fill: new Fill({
color: 'rgba(255, 255, 255, 0.2)'
}),
stroke: new Stroke({
color: 'rgba(0, 200, 255, 0.5)',
lineDash: [10, 10],
width: 2
}),
image: new CircleStyle({
radius: 5,
stroke: new Stroke({
color: 'rgba(0, 200, 255, 0.7)'
}),
fill: new Fill({
color: 'rgba(255, 255, 255, 0.2)'
})
})
})
});
//赋值
areaDraw = draw;
map.addInteraction(areaDraw);
var listener;
draw.on('drawstart',
function (evt) {
// set sketch
sketch = evt.feature;
/** @type {module:ol/coordinate~Coordinate|undefined} */
var tooltipCoord = evt.coordinate;
listener = sketch.getGeometry().on('change', function (evt) {
var geom = evt.target;
var output;
if (geom instanceof Polygon) {
output = formatArea(geom);
tooltipCoord = geom.getInteriorPoint().getCoordinates();
}
//measureTooltipElement.innerHTML = output;// 没有颜色
measureTooltipElement.innerHTML = "<span style='color: red;'>"+output+"</span>";
measureTooltip.setPosition(tooltipCoord);
});
//地图双击事件-绘制结束时有个小黄点
/* map.on('dblclick', function (evt) {
var point = new Point(evt.coordinate);
source.addFeature(new Feature(point));
});*/
}, this);
draw.on('drawend',
function (evt) {
//measureTooltipElement.className = 'tooltip tooltip-static';
measureTooltip.setOffset([0, -7]);
// unset sketch
sketch = null;
// unset tooltip so that a new one can be created
measureTooltipElement = null;
createMeasureTooltip();
unByKey(listener);
map.un('pointermove', pointerMoveHandler);
map.removeInteraction(draw);
areaHelpTooltipElement.classList.add('hidden');
}, this);
}
function createHelpTooltip() {
if (areaHelpTooltipElement) {
areaHelpTooltipElement.parentNode.removeChild(areaHelpTooltipElement);
}
areaHelpTooltipElement = document.createElement('div');
//areaHelpTooltipElement.className = 'tooltip hidden';
areaHelpTooltip = new Overlay({
element: areaHelpTooltipElement,
offset: [15, 0],
positioning: 'center-left'
});
map.addOverlay(areaHelpTooltip);
}
function createMeasureTooltip() {
if (measureTooltipElement) {
measureTooltipElement.parentNode.removeChild(measureTooltipElement);
}
measureTooltipElement = document.createElement('div');
//measureTooltipElement.className = 'tooltip tooltip-measure';
measureTooltip = new Overlay({
element: measureTooltipElement,
offset: [0, -15],
positioning: 'bottom-center'
});
map.addOverlay(measureTooltip);
}
// 量测调用
addAreaInteraction();
}
// 清空测量图层
export const clearMeasures = (map) =>{
// 清除测量距离
if(lineVectorLayer != null){
lineVectorLayer.getSource().clear();// 清除数据源
map.removeLayer(lineVectorLayer);// 清除图层
if(lineDraw != null){
// 禁止绘制
lineDraw.setActive(false);
// 结束测距绘制
map.removeInteraction(lineDraw);
lineDraw = null;
}
}
// 清除测面
if(areaVectorLayer != null){
areaVectorLayer.getSource().clear();// 清除数据源
map.removeLayer(areaVectorLayer);// 清除图层
if(areaDraw != null){
// 禁止绘制
areaDraw.setActive(false);
// 结束测面绘制
map.removeInteraction(areaDraw);
areaDraw = null;
}
}
// 清除overlays层
map.getOverlays().clear();
}使用方法：
<!-- 逻辑层 -->
<script>
***
***
export default {
data () {
return {
}
},
methods:{
}
}
</scripc>
<!-- renderjs层 -->
<script module="ol" lang="renderjs" type="module">
***
***
// 测距测面工具js
import {measureLineMethod,measurePolygonMethod,clearMeasures} from '../../utils/measure/measure.js'
export default {
data () {
return {
}
},
methods:{
method(){
//measureLineMethod(this.map);
measurePolygonMethod(this.map)
//clearMeasures(this.map);
}
}
}
</scripc>
