我正在使用ArcGIS JSAPI 4.12,希望使用空间幻象在地图上绘制军事符号。
当我将milsymbol.js添加到脚本中时,控制台返回错误
无法在模块外部使用import语句
所以我添加type="module"到脚本中,然后它返回
Uncaught ReferenceError: ms未定义
这是我的代码:
<link rel="stylesheet" href="https://js.arcgis.com/4.12/esri/css/main.css">
<script src="https://js.arcgis.com/4.12/"></script>
<script type="module" src="milsymbol-2.0.0/src/milsymbol.js"></script>
<script>
require([
"esri/Map",
"esri/views/MapView",
"esri/layers/MapImageLayer",
"esri/layers/FeatureLayer"
], function (Map, MapView, MapImageLayer, FeatureLayer) {
var symbol = new ms.Symbol("SFG-UCI----D", { size: 30 }).asCanvas(3);
var map = new Map({
basemap: "topo-vector"
});
var view = new MapView({
container: "viewDiv",
map: map,
center: [121, 23],
zoom: 7
});
});
</script>
所以,无论我是否添加type="module",总会有错误。但是在Spatial Illusions的官方文档中,脚本中没有type="module"。我现在真的很困惑。他们如何在不添加类型的情况下让它工作呢?
文件milsymbol.js
import { ms } from "./ms.js";
import Symbol from "./ms/symbol.js";
ms.Symbol = Symbol;
export { ms };
对我来说,这是一个编译问题。我已经添加了
"devDependencies": {
...
"@babel/cli": "^7.7.5",
"@babel/core": "^7.7.5",
"@babel/node": "^7.7.4",
"@babel/plugin-proposal-class-properties": "^7.7.4",
"@babel/plugin-transform-instanceof": "^7.8.3",
"@babel/plugin-transform-runtime": "^7.7.6",
"@babel/preset-env": "^7.7.5",
"@babel/register": "^7.7.4",
"@babel/runtime": "^7.9.6"
},
"dependencies": {
...
"@babel/plugin-transform-classes": "^7.15.4"
},
增加了.babelrc文件
{
"plugins": [
"@babel/plugin-proposal-class-properties",
"@babel/plugin-transform-instanceof",
"@babel/plugin-transform-classes"
],
"presets": ["@babel/preset-env"],
"env": {
"test": {
"plugins": ["@babel/plugin-transform-runtime"]
}
}
}
如果您想对模块使用import而不是require(),请更改或添加package中的type值到module。json文件
例子:
包中。json文件
{
"name": "appsample",
"version": "1.0.0",
"type": "module",
"description": "Learning Node",
"main": "app.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1"
},
"author": "Chikeluba Anusionwu",
"license": "ISC"
}
import http from 'http';
var host = '127.0.0.1',
port = 1992,
server = http.createServer();
server.on('request', (req, res) => {
res.writeHead(200, {"Content-Type": "text/plain"});
res.end("I am using type module in package.json file in this application.");
});
server.listen(port, () => console.log(
'Listening to server ${port}. Connection has been established.'));
对我来说,这是一个编译问题。我已经添加了
"devDependencies": {
...
"@babel/cli": "^7.7.5",
"@babel/core": "^7.7.5",
"@babel/node": "^7.7.4",
"@babel/plugin-proposal-class-properties": "^7.7.4",
"@babel/plugin-transform-instanceof": "^7.8.3",
"@babel/plugin-transform-runtime": "^7.7.6",
"@babel/preset-env": "^7.7.5",
"@babel/register": "^7.7.4",
"@babel/runtime": "^7.9.6"
},
"dependencies": {
...
"@babel/plugin-transform-classes": "^7.15.4"
},
增加了.babelrc文件
{
"plugins": [
"@babel/plugin-proposal-class-properties",
"@babel/plugin-transform-instanceof",
"@babel/plugin-transform-classes"
],
"presets": ["@babel/preset-env"],
"env": {
"test": {
"plugins": ["@babel/plugin-transform-runtime"]
}
}
}