interface TreeHelperConfig { id: string; children: string; pid: string; } // 默认配置 const DEFAULT_CONFIG: TreeHelperConfig = { id: 'id', children: 'children', pid: 'pid', }; // 获取配置。 Object.assign 从一个或多个源对象复制到目标对象 const getConfig = (config: Partial<TreeHelperConfig>) => Object.assign({}, DEFAULT_CONFIG, config); // tree from list // 列表中的树 export function listToTree<T = any>(list: any[], config: Partial<TreeHelperConfig> = {}): T[] { const conf = getConfig(config) as TreeHelperConfig; const nodeMap = new Map(); const result: T[] = []; const { id, children, pid } = conf; for (const node of list) { node[children] = node[children] || []; nodeMap.set(node[id], node); } for (const node of list) { const parent = nodeMap.get(node[pid]); (parent ? parent[children] : result).push(node); } return result; } export function treeToList<T = any>(tree: any, config: Partial<TreeHelperConfig> = {}): T { config = getConfig(config); const { children } = config; const result: any = [...tree]; for (let i = 0; i < result.length; i++) { if (!result[i][children!]) continue; result.splice(i + 1, 0, ...result[i][children!]); } return result; } export function findNode<T = any>( tree: any, func: Fn, config: Partial<TreeHelperConfig> = {}, ): T | null { config = getConfig(config); const { children } = config; const list = [...tree]; for (const node of list) { if (func(node)) return node; node[children!] && list.push(...node[children!]); } return null; } export function findNodeAll<T = any>( tree: any, func: Fn, config: Partial<TreeHelperConfig> = {}, ): T[] { config = getConfig(config); const { children } = config; const list = [...tree]; const result: T[] = []; for (const node of list) { func(node) && result.push(node); node[children!] && list.push(...node[children!]); } return result; } export function findPath<T = any>( tree: any, func: Fn, config: Partial<TreeHelperConfig> = {}, ): T | T[] | null { config = getConfig(config); const path: T[] = []; const list = [...tree]; const visitedSet = new Set(); const { children } = config; while (list.length) { const node = list[0]; if (visitedSet.has(node)) { path.pop(); list.shift(); } else { visitedSet.add(node); node[children!] && list.unshift(...node[children!]); path.push(node); if (func(node)) { return path; } } } return null; } export function findPathAll(tree: any, func: Fn, config: Partial<TreeHelperConfig> = {}) { config = getConfig(config); const path: any[] = []; const list = [...tree]; const result: any[] = []; const visitedSet = new Set(), { children } = config; while (list.length) { const node = list[0]; if (visitedSet.has(node)) { path.pop(); list.shift(); } else { visitedSet.add(node); node[children!] && list.unshift(...node[children!]); path.push(node); func(node) && result.push([...path]); } } return result; } export function filter<T = any>( tree: T[], func: (n: T) => boolean, // Partial 将 T 中的所有属性设为可选 config: Partial<TreeHelperConfig> = {}, ): T[] { // 获取配置 config = getConfig(config); const children = config.children as string; function listFilter(list: T[]) { return list .map((node: any) => ({ ...node })) .filter((node) => { // 递归调用 对含有children项 进行再次调用自身函数 listFilter node[children] = node[children] && listFilter(node[children]); // 执行传入的回调 func 进行过滤 return func(node) || (node[children] && node[children].length); }); } return listFilter(tree); } export function forEach<T = any>( tree: T[], func: (n: T) => any, config: Partial<TreeHelperConfig> = {}, ): void { config = getConfig(config); const list: any[] = [...tree]; const { children } = config; for (let i = 0; i < list.length; i++) { //func 返回true就终止遍历,避免大量节点场景下无意义循环,引起浏览器卡顿 if (func(list[i])) { return; } children && list[i][children] && list.splice(i + 1, 0, ...list[i][children]); } } /** * @description: Extract tree specified structure * @description: 提取树指定结构 */ export function treeMap<T = any>(treeData: T[], opt: { children?: string; conversion: Fn }): T[] { return treeData.map((item) => treeMapEach(item, opt)); } /** * @description: Extract tree specified structure * @description: 提取树指定结构 */ export function treeMapEach( data: any, { children = 'children', conversion }: { children?: string; conversion: Fn }, ) { const haveChildren = Array.isArray(data[children]) && data[children].length > 0; const conversionData = conversion(data) || {}; if (haveChildren) { return { ...conversionData, [children]: data[children].map((i: number) => treeMapEach(i, { children, conversion, }), ), }; } else { return { ...conversionData, }; } } /** * 递归遍历树结构 * @param treeDatas 树 * @param callBack 回调 * @param parentNode 父节点 */ export function eachTree(treeDatas: any[], callBack: Fn, parentNode = {}) { treeDatas.forEach((element) => { const newNode = callBack(element, parentNode) || element; if (element.children) { eachTree(element.children, callBack, newNode); } }); }