update：车案例代码结构的修改

src/examples/movingTarget/vehicle/vehicle-function.js

-export function addVehicle() {
-    const script = document.createElement('script');
-    script.src = 'https://cesium.com/downloads/cesiumjs/releases/1.99/Build/Cesium/Cesium.js';
-    script.onload = () => {
-        window.Cesium.Ion.defaultAccessToken = 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJqdGkiOiI3Njg4ZWU5Yi1iZDhiLTRhYmUtOTRiYS04YjM5NmUwNjVmMDMiLCJpZCI6MjI3MzQ3LCJpYXQiOjE3MjA1MjA4Mjh9.E5XW4LnwgfVAaBC-znaYr61m4yK0-j2qEQhi9qwFFPE'
+export function addVehicle(viewer) {
+    const czml = [
+        {
+            id: "document",
+            name: "Vehicle",
+            version: "1.0",
+            clock: {
+                interval: "2019-08-28T04:00:00Z/2019-08-28T04:20:00Z",
+                currentTime: "2019-08-28T04:00:00.00Z",
+                multiplier: 1,
+                range: "LOOP_STOP",
+                step: "SYSTEM_CLOCK_MULTIPLIER"
+                }
+        },
+        {
+            id: "path",
+            name: "path for Vehicle",
+            description: "<p>this is a description</p>",
+            availability: "2019-08-28T04:00:00Z/2019-08-28T04:20:00Z",
+            path: {
+                material: {
+                    polylineOutline: {
+                        color: {
+                            rgba: [255, 0, 255, 255],
+                        },
+                        outlineColor: {
+                            rgba: [0, 255, 255, 255],
+                        },
+                        outlineWidth: 5    
+                    }, 
+                },
+                width: 8,   // 折线宽度
+                leadTime: 5,  
+                trailTime: 50000,
+                resolution: 5,
+                },
+                orientation: {
+                "velocityReference": "#position"
+                },
+                model: {
+                    gltf: 'https://raw.githubusercontent.com/jinlinchao123/Cesium-assets/main/3Dmodel/CesiumMilkTruck.glb',
+                    minimumPixelSize: 128,
+                },
+                position: {
+                    epoch: "2019-08-28T04:00:00.00Z",
+                    cartographicDegrees: [
+                        0, 120, 30, 0,
+                        1200, 121, 30, 0
+                    ]
+                }
+        },
+    ];
 
-        const viewer = new window.Cesium.Viewer('cesiumContainer', {
-            infoBox: false,
-            shouldAnimate: true
-        });
-
-        const czml = [
-            {
-                id: "document",
-                name: "Vehicle",
-                version: "1.0",
-                clock: {
-                  interval: "2019-08-28T04:00:00Z/2019-08-28T04:20:00Z",
-                  currentTime: "2019-08-28T04:00:00.00Z",
-                  multiplier: 1,
-                  range: "LOOP_STOP",
-                  step: "SYSTEM_CLOCK_MULTIPLIER"
-                 }
-            },
-            {
-                id: "path",
-                name: "path for Vehicle",
-                description: "<p>this is a description</p>",
-                availability: "2019-08-28T04:00:00Z/2019-08-28T04:20:00Z",
-                path: {
-                    material: {
-                        polylineOutline: {
-                            color: {
-                                rgba: [255, 0, 255, 255],
-                            },
-                            outlineColor: {
-                                rgba: [0, 255, 255, 255],
-                            },
-                            outlineWidth: 5    
-                        }, 
-                    },
-                    width: 8,   // 折线宽度
-                    leadTime: 5,  
-                    trailTime: 50000,
-                    resolution: 5,
-                 },
-                 orientation: {
-                    "velocityReference": "#position"
-                 },
-                 model: {
-                     gltf: 'https://raw.githubusercontent.com/jinlinchao123/Cesium-assets/main/3Dmodel/CesiumMilkTruck.glb',
-                     minimumPixelSize: 128,
-                 },
-                 position: {
-                     epoch: "2019-08-28T04:00:00.00Z",
-                     cartographicDegrees: [
-                         0, 120, 30, 0,
-                         1200, 121, 30, 0
-                     ]
-                 }
-            },
-        ];
-
-        var dataSourcePromise = viewer.dataSources.add(Cesium.CzmlDataSource.load(czml));
-        dataSourcePromise.then(function (dataSource) {
-            // 根据模型所在的实体去进行加载
-            viewer.trackedEntity = dataSource.entities.getById('path');
-        }).catch(function (error) {
-          console.error(error);
-        });
-
-    };
-    document.head.appendChild(script);
-
-    const link = document.createElement('link');
-    link.rel = 'stylesheet';
-    link.href = 'https://cesium.com/downloads/cesiumjs/releases/1.119/Build/Cesium/Widgets/widgets.css';
-    document.head.appendChild(link);
+    var dataSourcePromise = viewer.dataSources.add(Cesium.CzmlDataSource.load(czml));
+    dataSourcePromise.then(function (dataSource) {
+        // 根据模型所在的实体去进行加载
+        viewer.trackedEntity = dataSource.entities.getById('path');
+    }).catch(function (error) {
+        console.error(error);
+    });
 }

src/examples/movingTarget/vehicle/vehicle.vue

 <template>
     <div id="cesiumContainer" class="cesium-container"></div>
 </template>
+
 <script setup>
 import { onMounted } from 'vue';
 import { addVehicle } from './function';
+
+let viewer;
+
 onMounted(() => {
-    addVehicle()
+    const script = document.createElement('script');
+    script.src = 'https://cesium.com/downloads/cesiumjs/releases/1.99/Build/Cesium/Cesium.js';
+    script.onload = () => {
+        window.Cesium.Ion.defaultAccessToken = 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJqdGkiOiI3Njg4ZWU5Yi1iZDhiLTRhYmUtOTRiYS04YjM5NmUwNjVmMDMiLCJpZCI6MjI3MzQ3LCJpYXQiOjE3MjA1MjA4Mjh9.E5XW4LnwgfVAaBC-znaYr61m4yK0-j2qEQhi9qwFFPE'
+
+        viewer = new window.Cesium.Viewer('cesiumContainer', {
+            infoBox: false,
+            shouldAnimate: true
+        });
+
+        addVehicle(viewer)
+
+    };
+    document.head.appendChild(script);
+    const link = document.createElement('link');
+    link.rel = 'stylesheet';
+    link.href = 'https://cesium.com/downloads/cesiumjs/releases/1.119/Build/Cesium/Widgets/widgets.css';
+    document.head.appendChild(link);
 });
 </script>
 
 <style>
 .cesium-container {
-width: 100%;
-height: 100vh;
+    width: 100%;
+    height: 100vh;
 }
 </style>
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