{"id":10021090,"date":"2025-11-25T18:51:42","date_gmt":"2025-11-25T10:51:42","guid":{"rendered":"https:\/\/itmax.cn\/?p=10021090"},"modified":"2025-11-25T18:51:42","modified_gmt":"2025-11-25T10:51:42","slug":"%e6%b6%a8%e8%a7%81%e8%af%86%e4%ba%86%ef%bc%8cerror-cause-%e8%ae%a9-javascript-%e9%94%99%e8%af%af%e8%b0%83%e8%af%95%e6%9b%b4%e8%bd%bb%e6%9d%be","status":"publish","type":"post","link":"https:\/\/itmax.cn\/?p=10021090","title":{"rendered":"\u6da8\u89c1\u8bc6\u4e86\uff0cError.cause \u8ba9 JavaScript \u9519\u8bef\u8c03\u8bd5\u66f4\u8f7b\u677e"},"content":{"rendered":"

1. \u524d\u8a00<\/h2>\n

\u5728 JavaScript \u4e2d\uff0c\u629b\u51fa\u9519\u8bef\u5f88\u5bb9\u6613\uff0c\u4f46\u8ffd\u6eaf\u539f\u56e0\u5374\u6709\u4e9b\u9ebb\u70e6\uff0c\u8fd9\u5c31\u662f cause<\/code>\u5c5e\u6027\u7684\u7528\u6b66\u4e4b\u5730\u3002<\/p>\n

\u8fd9\u662f\u6211\u4eec\u4f20\u7edf\u7684\u5904\u7406\u9519\u8bef\u7684\u505a\u6cd5\uff1a<\/p>\n

try {\n  JSON.parse("{ bad json }");\n} catch (err) {\n  throw new Error("Something went wrong: " + err.message);\n}<\/code><\/pre>\n
\u867d\u7136\u5305\u88c5\u4e86\u9519\u8bef\uff0c\u4f46\u5df2\u7ecf\u4e22\u5931\u4e86\u539f\u59cb\u7684\u5806\u6808\u4fe1\u606f\u548c\u9519\u8bef\u7c7b\u578b\u3002<\/p>\n
\u5f53\u95ee\u9898\u53d1\u751f\u65f6\uff0c\u4f60\u53ea\u80fd\u770b\u5230\u6700\u9876\u5c42\u7684\u9519\u8bef\u4fe1\u606f\uff0c\u5374\u4e0d\u77e5\u9053\u6839\u672c\u539f\u56e0\u662f\u4ec0\u4e48\u3002<\/p>\n
\u4f60\u597d\uff0c\u6211\u662f\u51b4\u7fbd\u3002\u524d\u7aef\u8d44\u8baf\u3001\u524d\u7aef\u5e72\u8d27\uff0c\u6b22\u8fce\u5173\u6ce8\u516c\u4f17\u53f7\uff1a\u51b4\u7fbd<\/p>\n
2. \u5f15\u5165 Error.cause<\/h2>\n
ES2022 \u5f15\u5165\u4e86 Error.cause<\/a> \u5c5e\u6027\uff0c\u53ef\u4ee5\u4fdd\u7559\u539f\u59cb\u9519\u8bef\u4fe1\u606f\uff1a<\/p>\n
try {\n  try {\n    JSON.parse("{ bad json }");\n  } catch (err) {\n    throw new Error("Something went wrong", { cause: err });\n  }\n} catch (err) {\n  console.error(err.stack);\n  console.error("Caused by:", err.cause.stack);\n}<\/code><\/pre>\n
\u6b64\u65f6\u4f60\u53ef\u4ee5\u770b\u5230\u5b8c\u6574\u7684\u9519\u8bef\u94fe\uff1a<\/p>\n
Error: Something went wrong\n    at ...\nCaused by: SyntaxError: Unexpected token b in JSON at position 2\n    at JSON.parse (<anonymous>)\n    at ...<\/code><\/pre>\n
\u73b0\u5728\uff0c\u4f60\u65e2\u4fdd\u7559\u4e86\u539f\u59cb\u9519\u8bef\uff0c\u53c8\u80fd\u63d0\u4f9b\u6e05\u6670\u7684\u9876\u5c42\u9519\u8bef\u4fe1\u606f\u3002<\/p>\n
3. \u5b9e\u9645\u5e94\u7528\u793a\u4f8b<\/h2>\n
\u8ba9\u6211\u4eec\u770b\u4e00\u4e2a\u66f4\u5b9e\u9645\u7684\u4f8b\u5b50\uff1a<\/p>\n
function fetchUserData() {\n  try {\n    JSON.parse("{ broken: true }"); \/\/ \u2190 \u8fd9\u91cc\u4f1a\u5931\u8d25\n  } catch (parseError) {\n    throw new Error("Failed to fetch user data", { cause: parseError });\n  }\n}\n\ntry {\n  fetchUserData();\n} catch (err) {\n  console.error(err.message); \/\/ "Failed to fetch user data"\n  console.error(err.cause); \/\/ [SyntaxError: Unexpected token b in JSON]\n  console.error(err.cause instanceof SyntaxError); \/\/ true\n}<\/code><\/pre>\n
\u53ef\u4ee5\u770b\u5230\u4ee3\u7801\u975e\u5e38\u6e05\u6670\u76f4\u89c2\u3002<\/p>\n
\u800c\u4e14 cause \u5c5e\u6027\u88ab\u5b9a\u4e49\u4e3a\u4e0d\u53ef\u679a\u4e3e<\/strong>\uff0c\u56e0\u6b64\u5b83\u4e0d\u4f1a\u6c61\u67d3\u65e5\u5fd7\u6216 for…in \u5faa\u73af\uff0c\u9664\u975e\u4f60\u663e\u5f0f\u8bbf\u95ee\u5b83\u3002<\/p>\n
4. \u81ea\u5b9a\u4e49\u9519\u8bef\u7c7b<\/h2>\n
\u4f60\u53ef\u4ee5\u5728\u81ea\u5b9a\u4e49\u9519\u8bef\u7c7b\u4e2d\u4f7f\u7528 cause<\/code> \u5c5e\u6027\uff1a<\/p>\n
class DatabaseError extends Error {\n  constructor(message, { cause } = {}) {\n    super(message, { cause });\n    this.name = "DatabaseError";\n  }\n}<\/code><\/pre>\n
\u5982\u679c\u4f60\u7684\u8fd0\u884c\u73af\u5883\u662f ES2022+\uff0c\u8fd9\u5df2\u7ecf\u8db3\u591f\u4e86\uff1asuper(message, { cause })<\/code> \u4f1a\u81ea\u52a8\u5904\u7406\u4e00\u5207\u3002<\/p>\n
\u5bf9\u4e8e TypeScript \u7528\u6237\uff0c\u786e\u4fdd tsconfig.json<\/code> \u914d\u7f6e\u4e86\uff1a<\/p>\n
{\n  "compilerOptions": {\n    "target": "es2022",\n    "lib": ["es2022"]\n  }\n}<\/code><\/pre>\n
\u5426\u5219\uff0c\u5728\u5c06 { cause }<\/code> \u4f20\u9012\u7ed9 Error \u6784\u9020\u51fd\u6570\u65f6\u53ef\u80fd\u4f1a\u770b\u5230\u7c7b\u578b\u9519\u8bef\u3002<\/p>\n
5. \u66f4\u597d\u7684\u6d4b\u8bd5\u65ad\u8a00<\/h2>\n
\u5047\u8bbe\u4f60\u7684\u670d\u52a1\u629b\u51fa\u4e86\u4e00\u4e2a UserCreationError<\/code>\uff0c\u8fd9\u662f\u7531\u4e00\u4e2a ValidationError<\/code> \u5f15\u53d1\u7684\u3002<\/p>\n
\u4f60\u53ef\u4ee5\u8fd9\u6837\u5199\u65ad\u8a00\uff1a<\/p>\n
expect(err.cause).toBeInstanceOf(ValidationError);<\/code><\/pre>\n
\u8fd9\u6837\u6d4b\u8bd5\u4f1a\u66f4\u6e05\u6670\u3001\u66f4\u5065\u58ee\u3002<\/p>\n
6. \u6ce8\u610f\u4e8b\u9879<\/h2>\n
\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cconsole.error(err)<\/code> \u53ea\u4f1a\u6253\u5370\u9876\u5c42\u9519\u8bef\u3002cause<\/code>\u94fe\u4e0d\u4f1a\u81ea\u52a8\u663e\u793a\uff0c\u56e0\u6b64\u9700\u8981\u624b\u52a8\u6253\u5370\uff1a<\/p>\n
console.error(err);\nconsole.error("Caused by:", err.cause);<\/code><\/pre>\n
\u5c3d\u7ba1 cause \u5f88\u597d\uff0c\u4f46\u4e5f\u4e0d\u8981\u6ee5\u7528\u3002\u6bcf\u4e2a\u5c0f\u9519\u8bef\u90fd\u5305\u88c5\u53ef\u80fd\u66f4\u4e71\uff0c\u56e0\u6b64\u53ea\u5728\u771f\u6b63\u9700\u8981\u4e0a\u4e0b\u6587\u7684\u65f6\u5019\u4f7f\u7528\u3002<\/p>\n
7. \u9012\u5f52\u6253\u5370\u5b8c\u6574\u9519\u8bef\u94fe<\/h2>\n
\u8fd9\u662f\u4e00\u4e2a\u5b89\u5168\u904d\u5386\u9519\u8bef\u94fe\u7684\u5de5\u5177\u51fd\u6570\uff1a<\/p>\n
function logErrorChain(err, level = 0) {\n  if (!err) return;\n  console.error(" ".repeat(level * 2) + `${err.name}: ${err.message}`);\n\n  if (err.cause instanceof Error) {\n    logErrorChain(err.cause, level + 1);\n  } else if (err.cause) {\n    console.error(" ".repeat((level + 1) * 2) + String(err.cause));\n  }\n}<\/code><\/pre>\n
\u5982\u679c\u9700\u8981\u5b8c\u6574\u5806\u6808\u4fe1\u606f\uff1a<\/p>\n
function logFullErrorChain(err) {\n  let current = err;\n  while (current) {\n    console.error(current.stack);\n    current = current.cause instanceof Error ? current.cause : null;\n  }\n}<\/code><\/pre>\n
\u5bf9\u4e8e\u7ed3\u6784\u590d\u6742\u3001\u53ef\u80fd\u5728\u4e0d\u540c\u5c42\u7ea7\u51fa\u73b0\u591a\u79cd\u6545\u969c\u7684\u7cfb\u7edf\u6765\u8bf4\uff0c\u8fd9\u975e\u5e38\u6709\u7528\u3002<\/p>\n
8. \u8de8\u5c42\u9519\u8bef\u94fe\u793a\u4f8b<\/h2>\n
\u5047\u8bbe\u8c03\u7528\u6d41\u7a0b\u5982\u4e0b\uff1a<\/p>\n
    \n
  1. \u6570\u636e\u5e93\u8fde\u63a5\u5931\u8d25\uff0c\u629b\u51fa ConnectionTimeoutError<\/code><\/li>\n
  2. \u6355\u83b7\u540e\u5305\u88c5\u6210 DatabaseError<\/code><\/li>\n
  3. \u518d\u6b21\u6355\u83b7\u5e76\u5305\u88c5\u6210 ServiceUnavailableError<\/code><\/li>\n<\/ol>\n
    class ConnectionTimeoutError extends Error {}\nclass DatabaseError extends Error {}\nclass ServiceUnavailableError extends Error {}\n\ntry {\n  try {\n    try {\n      throw new ConnectionTimeoutError("DB connection timed out");\n    } catch (networkErr) {\n      throw new DatabaseError("Failed to connect to database", { cause: networkErr });\n    }\n  } catch (dbErr) {\n    throw new ServiceUnavailableError("Unable to save user data", { cause: dbErr });\n  }\n} catch (finalErr) {\n  logErrorChain(finalErr);\n}<\/code><\/pre>\n
    \u63a7\u5236\u53f0\u8f93\u51fa\uff1a<\/p>\n
    ServiceUnavailableError: Unable to save user data\n  DatabaseError: Failed to connect to database\n    ConnectionTimeoutError: DB connection timed out<\/code><\/pre>\n
    \u53ef\u4ee5\u770b\u5230\uff0c\u9519\u8bef\u94fe\u63d0\u4f9b\u4e86\u4e00\u4e2a\u6e05\u6670\u7684\u89c6\u56fe\uff0c\u544a\u8bc9\u4f60\u53d1\u751f\u4e86\u4ec0\u4e48\u4ee5\u53ca\u5728\u54ea\u91cc\u53d1\u751f\u7684\u3002<\/p>\n
    9. \u652f\u6301\u5ea6<\/h2>\n
    .cause<\/code> \u53c2\u6570\u5728\u6240\u6709\u73b0\u4ee3\u73af\u5883\u4e2d\u90fd\u652f\u6301\uff1a<\/p>\n