对于cesium entiy的增删改查 我们来封装一个layer来统一管理
类似arcgis js 的GraphicLayer

中间数据管理类

• import {Layer} from "./Layer";
•  
• export abstract class DataSourceLayer extends Layer {
• type: string = "DataSourceLayer";
•  
• protected _addToMap(map: any) {
• map.dataSources.add(this.cesiumObj);
• }
•  
• protected _removeByMap(destroy: boolean = true) {
• this.map.dataSources.remove(this.cesiumObj);
• this.cesiumObj = null;
• }
•  
• on(eventName: string, callBacl: Function): this {
• return this;
• }
•  
• off(): this {
• return this;
• }
• }

json序列化工具
```javascript

/**

• 将cesium对象json化
  */
  export class CesiumToJson {
  private static excludes = ["_definitionChanged", "_children", "_propertyNames", "_type_"];
  public static entityToJson(entity: any): any {
  const option:any = {};
  if (!entity) {
  return option;
  }
  for (let key in entity) {
  if (!key.startsWith("_")) {
  continue;
  }
  if (this.excludes.indexOf(key) !== -1) {
  continue;
  }
  const value = entity[key];
  if (!value) {
  continue;
  }
  if (Object.prototype.toString.call(value) == "[object Function]") {
  continue;
  }
  key = key.substr(1, key.length);

  • if (key === "material") {
  • option[key] = this.entityToJson(value);
  • // 打包可能会引起问题，需要注意（未验证）
  • option[key].type = value.constructor.name;
  • continue;
  • }
  • if (Object.prototype.toString.call(value) == "[object Object]") {
  • console.log(key, value);
  • if (!(Object.prototype.toString.call(value._value) == "[object Undefined]")) {
  • option[key] = value._value;
  • } else if (!(Object.prototype.toString.call(value._callback) == "[object Undefined]")) {
  • // 如果是动态执行方法的，暂时不支持保存，后期想办法解析
  • continue;
  • } else {
  • option[key] = this.entityToJson(value);
  • }
  • } else {
  • option[key] = value;
  • }
  • }
  • return option;

  }
  public static entitiesToJson(entities: any): any {
  return entities.values.map((entity: any) => {
  return this.entityToJson(entity);
  })
  }

   

  public static jsonToEntityObj(option: any) {
  for (let key in option) {
  const value = option[key];
  if (key === "material") {
  let materialProperty = null;
  const type = value.type;
  delete value.type;
  let material = Cesium[type];
  if (material) {
  materialProperty = new material();
  for (const field in value) {
  materialProperty[field] = value[field];
  }
  }
  option[key] = materialProperty;
  } else if (Object.prototype.toString.call(value) == "[object Object]") {
  this.jsonToEntityObj(value);

 更多参考 https://xiaozhuanlan.com/topic/5836490271