将地理 WGS 84 转换为 Web 墨卡托 102100

Converting geographic WGS 84 to Web Mercator 102100

本文关键字：Web 102100 转换 WGS      更新时间：2023-09-26

我正在尝试将地理坐标系转换为 Esri Webmercator，但是当我进行转换时，生成的 x 和 y 的值为 0000003232112222...和00000012665321....这很奇怪，因为坐标不存在。

var positions = [];
positions.push(x, y);
var g = new esri.geometry.Point(positions);
g = esri.geometry.geographicToWebMercator(g);
x = g.x;
y = g.y;

您应该尝试esri/geometry/webMercatorUtils模块中的geographicToWebMercator方法。请参阅详细文档。

        //a point in GCS_WGS_1984(wkid is 4326)
        var point = new Point(-118.15, 33.80, new SpatialReference({
            wkid: 4326
        }));
        var pointWebMercator = webMercatorUtils.geographicToWebMercator(point);
        alert("the point in 102100 is ( " + pointWebMercator.x + "," + pointWebMercator.y + " )");

现场演示：

<!DOCTYPE html>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no" />
    <title>Converting geographic WGS 84 to Web Mercator 102100</title>
    <link rel="stylesheet" href="https://js.arcgis.com/3.20/esri/css/esri.css">
    <style>
        html,
        body,
        #map {
            height: 100%;
            margin: 0;
            padding: 0;
        }
    </style>
    <script src="https://js.arcgis.com/3.20/"></script>
    <script>
        var map;
        require(["esri/map", "esri/geometry/Point", "esri/SpatialReference", "esri/geometry/webMercatorUtils", "dojo/domReady!"], function (Map, Point, SpatialReference, webMercatorUtils) {
            map = new Map("map", {
                basemap: "topo", //For full list of pre-defined basemaps, navigate to http://arcg.is/1JVo6Wd
                center: [-122.45, 37.75], // longitude, latitude
                zoom: 13
            });
            //a point in GCS_WGS_1984(wkid is 4326)
            var point = new Point(-118.15, 33.80, new SpatialReference({
                wkid: 4326
            }));
            var pointWebMercator = webMercatorUtils.geographicToWebMercator(point);
            alert("the point in 102100 is ( " + pointWebMercator.x + "," + pointWebMercator.y + " )");
        });
    </script>
</head>
<body>
    <div id="map"></div>
</body>
</html>

希望它能帮助你。

实际上，

您不必转换纬度/经度即可向 webmercator 中的底图添加点。

您可以通过几种不同的方式直接使用纬度/经度创建点（API 将在内部执行从地理到网络墨卡托的转换）。此功能从版本 3.3（2013 年 1 月）开始可用。

var point = new Point(-98, 38); // note that longitude(x) comes before the latitude(y).
// or as an array
var point = new Point([-98, 38]);
// or as an object
var point = new Point({latitude: 38, longitude: -98});

https://developers.arcgis.com/javascript/3/jsapi/point-amd.html#point4

相关文章：