1 line
16 KiB
JavaScript
1 line
16 KiB
JavaScript
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parentId = item[pidName];\n\n // \u5982\u679c\u8be5\u9879\u4e0d\u5728 record \u4e2d\uff0c\u5219\u653e\u5165 record\u3002\u5982\u679c\u8be5\u9879\u5df2\u5b58\u5728 \uff08\u53ef\u80fd\u7531\u522b\u7684\u9879\u6784\u5efa pid \u52a0\u5165\uff09\uff0c\u5219\u5408\u5e76\u8be5\u9879\u548c\u5df2\u5b58\u5728\u7684\u6570\u636e\n record[id] = !record[id] ? item : { ...item, ...record[id] };\n\n const treeItem = record[id];\n\n if (parentId === rootId) {\n // \u5982\u679c\u662f\u6839\u5143\u7d20\uff0c\u5219\u52a0\u5165\u7ed3\u679c\u96c6\n root.push(treeItem);\n } else {\n // \u5982\u679c\u7236\u5143\u7d20\u4e0d\u5b58\u5728\uff0c\u5219\u521d\u59cb\u5316\u7236\u5143\u7d20\n if (!record[parentId]) {\n record[parentId] = {};\n }\n // \u5982\u679c\u7236\u5143\u7d20\u6ca1\u6709 children, \u5219\u521d\u59cb\u5316\n if (!record[parentId][childName]) {\n record[parentId][childName] = [];\n }\n\n record[parentId][childName].push(treeItem);\n }\n });\n\n return root;\n}\n')),(0,a.kt)("p",null,"\u65f6\u95f4\u590d\u6742\u5ea6\u5206\u6790\uff1a\u7ecf\u5386\u4e86\u4e00\u8f6e\u8fed\u4ee3\uff0c\u5047\u8bbe\u6709 n \u4e2a\u5143\u7d20\uff0c\u90a3\u4e48\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a O(n)\u3002"),(0,a.kt)("h4",{id:"\u53d8\u4f53\u4e8c"},"\u53d8\u4f53\u4e8c"),(0,a.kt)("p",null,"record \u5b57\u5178\u4ec5\u8bb0\u5f55 id \u4e0e children \u7684\u6620\u5c04\u5173\u7cfb\uff0c\u4ee3\u7801\u66f4\u7cbe\u7b80\uff1a"),(0,a.kt)("pre",null,(0,a.kt)("code",{parentName:"pre",className:"language-js"},'function listToTree(\n list,\n rootId = null,\n { idName = "id", pidName = "pid", childName = "children" } = {}\n) {\n const record = {}; // \u7528\u7a7a\u95f4\u6362\u65f6\u95f4\uff0c\u4ec5\u7528\u4e8e\u8bb0\u5f55 children\n const root = [];\n\n list.forEach((item) => {\n const newItem = Object.assign({}, item); // \u5982\u6709\u9700\u8981\uff0c\u53ef\u4ee5\u590d\u5236 item \uff0c\u53ef\u4ee5\u4e0d\u5f71\u54cd list \u4e2d\u539f\u6709\u7684\u5143\u7d20\u3002\n const id = newItem[idName];\n const parentId = newItem[pidName];\n\n // \u5982\u679c\u5f53\u524d id \u7684 children \u5df2\u5b58\u5728\uff0c\u5219\u52a0\u5165 children \u5b57\u6bb5\u4e2d\uff0c\u5426\u5219\uff0c\u521d\u59cb\u5316 children\n // item \u4e0e record[id] \u5f15\u7528\u540c\u4e00\u4efd children\uff0c\u540e\u7eed\u8fed\u4ee3\u4e2d\u66f4\u65b0 record[parendId] \u5c31\u4f1a\u53cd\u6620\u5230 item \u4e2d\n newItem[childName] = record[id] ? record[id] : (record[id] = []);\n\n if (parentId === rootId) {\n root.push(newItem);\n } else {\n if (!record[parentId]) {\n record[parentId] = [];\n }\n record[parentId].push(newItem);\n }\n });\n\n return root;\n}\n')),(0,a.kt)("p",null,"\u65f6\u95f4\u590d\u6742\u5ea6\u5206\u6790\uff1a\u7ecf\u5386\u4e86\u4e00\u8f6e\u8fed\u4ee3\uff0c\u5047\u8bbe\u6709 n \u4e2a\u5143\u7d20\uff0c\u90a3\u4e48\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a O(n)\u3002"),(0,a.kt)("h3",{id:"\u4ee3\u7801\u6f14\u793a\u53ca\u603b\u7ed3"},"\u4ee3\u7801\u6f14\u793a\u53ca\u603b\u7ed3"),(0,a.kt)("p",null,(0,a.kt)("a",{parentName:"p",href:"https://codesandbox.io/s/practical-sun-vo4yi?file=/src/App.js"},"Code Sandbox - List to Tree")),(0,a.kt)("ul",null,(0,a.kt)("li",{parentName:"ul"},"\u9012\u5f52\u6cd5\uff1a\u5728\u6570\u636e\u91cf\u589e\u5927\u7684\u65f6\u5019\uff0c\u6027\u80fd\u4f1a\u6025\u5267\u4e0b\u964d\u3002\u597d\u5904\u662f\u53ef\u4ee5\u5728\u6784\u5efa\u6811\u7684\u8fc7\u7a0b\u4e2d\uff0c\u7ed9\u8282\u70b9\u6dfb\u52a0\u5c42\u7ea7\u4fe1\u606f\u3002"),(0,a.kt)("li",{parentName:"ul"},"\u8fed\u4ee3\u6cd5\uff1a\u901f\u5ea6\u5feb\u3002\u4f46\u5982\u679c\u60f3\u8981\u4e0d\u5f71\u54cd\u6e90\u6570\u636e\uff0c\u9700\u8981\u5728 record \u4e2d\u5b58\u50a8\u4e00\u4efd\u590d\u5236\u7684\u6570\u636e\uff0c\u4e14\u65e0\u6cd5\u5728\u6784\u5efa\u7684\u8fc7\u7a0b\u4e2d\u5f97\u77e5\u8282\u70b9\u7684\u5c42\u7ea7\u4fe1\u606f\uff0c\u9700\u8981\u6784\u5efa\u5b8c\u540e\u518d\u6b21\u6df1\u5ea6\u4f18\u5148\u904d\u5386\u83b7\u53d6\u3002"),(0,a.kt)("li",{parentName:"ul"},"\u8fed\u4ee3\u6cd5\u53d8\u4f53\u4e00\uff1a\u6309\u9700\u521b\u5efa children\uff0c\u53ef\u4ee5\u907f\u514d\u7a7a\u7684 children \u5217\u8868\u3002")))}m.isMDXComponent=!0}}]); |