{"id":3780,"date":"2024-11-10T09:27:23","date_gmt":"2024-11-10T01:27:23","guid":{"rendered":"https:\/\/fwq.ai\/blog\/3780\/"},"modified":"2024-11-10T09:27:23","modified_gmt":"2024-11-10T01:27:23","slug":"%e4%b8%ba%e4%bb%80%e4%b9%88%e9%9c%80%e8%a6%81%e7%b1%bb%e5%9e%8b%e4%bf%9d%e6%8a%a4%ef%bc%9f%e6%8e%a2%e7%b4%a2%e4%b8%8d%e5%90%8c%e7%b1%bb%e5%9e%8b%e5%8f%8a%e5%85%b6%e7%94%a8%e4%be%8b","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/3780\/","title":{"rendered":"\u4e3a\u4ec0\u4e48\u9700\u8981\u7c7b\u578b\u4fdd\u62a4\uff1f\u63a2\u7d22\u4e0d\u540c\u7c7b\u578b\u53ca\u5176\u7528\u4f8b"},"content":{"rendered":"

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\u5728 \u4e2d\uff0c\u7c7b\u578b\u4fdd\u62a4<\/strong> \u5728\u4f7f\u4ee3\u7801\u5e93\u66f4\u52a0\u53ef\u9760\u3001\u5bf9\u5f00\u53d1\u4eba\u5458\u66f4\u53cb\u597d\u65b9\u9762\u53d1\u6325\u7740\u91cd\u8981\u4f5c\u7528\u3002\u5b83\u4eec\u901a\u8fc7\u5141\u8bb8\u5f00\u53d1\u4eba\u5458\u7f29\u5c0f\u7c7b\u578b\u6765\u5e2e\u52a9\u786e\u4fdd\u7c7b\u578b\u5b89\u5168\uff0c\u8fd9\u6709\u52a9\u4e8e\u51cf\u5c11\u8fd0\u884c\u65f6\u9519\u8bef\u5e76\u4f7f\u4ee3\u7801\u66f4\u6613\u4e8e\u7406\u89e3\u548c\u7ef4\u62a4\u3002<\/p>\n

\u4ec0\u4e48\u662f\u7c7b\u578b\u4fdd\u62a4\uff1f<\/strong><\/p>\n

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\u4e3a\u4ec0\u4e48\u9700\u8981\u7c7b\u578b\u4fdd\u62a4\uff1f<\/strong><\/p>\n

\u5728 javascript \u4e2d\uff0c\u60a8\u7ecf\u5e38\u4f1a\u9047\u5230\u53ef\u80fd\u5177\u6709\u591a\u79cd\u7c7b\u578b\u7684\u503c\uff0c\u4f8b\u5982\u8fd4\u56de\u5b57\u7b26\u4e32\u6216\u6570\u5b57\u7684\u51fd\u6570\u3002\u5982\u679c\u6ca1\u6709\u7c7b\u578b\u4fdd\u62a4\uff0ctypescript \u5c06\u65e0\u6cd5\u786e\u5b9a\u786e\u5207\u7684\u7c7b\u578b\uff0c\u4ece\u800c\u5bfc\u81f4\u6f5c\u5728\u7684\u8fd0\u884c\u65f6\u9519\u8bef\u548c\u4e0d\u6b63\u786e\u7684\u884c\u4e3a\u3002\u7c7b\u578b\u9632\u62a4\u5141\u8bb8\u60a8\u5728\u8fd0\u884c\u65f6\u68c0\u67e5\u503c\u7684\u7c7b\u578b\uff0c\u5e2e\u52a9 typescript \u7f29\u5c0f\u7c7b\u578b\u8303\u56f4\u5e76\u63d0\u4f9b\u66f4\u51c6\u786e\u7684\u7c7b\u578b\u68c0\u67e5\u3002<\/p>\n

\u5e38\u89c1\u7c7b\u578b\u7684\u7c7b\u578b\u4fdd\u62a4\u53ca\u5176\u7528\u4f8b<\/strong><\/p>\n

1\u3002 typeof \u7c7b\u578b\u4fdd\u62a4<\/strong><\/p>\n

\u7528\u4f8b<\/strong>\uff1a\u539f\u59cb\u7c7b\u578b\u7684\u57fa\u672c\u7c7b\u578b\u68c0\u67e5\u3002
\u793a\u4f8b<\/strong>\uff1a<\/p>\n

function printvalue(value: string | number) {\n  if (typeof value === \"string\") {\n    console.log(`string value: ${value.touppercase()}`);\n  } else {\n    console.log(`number value: ${value.tofixed(2)}`);\n  }\n}\n<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u8bf4\u660e<\/strong>\uff1atypeof \u5bf9\u4e8e\u539f\u59cb\u7c7b\u578b\uff08\u5b57\u7b26\u4e32\u3001\u6570\u5b57\u3001\u5e03\u5c14\u503c\uff09\u6709\u6548\u3002\u5b83\u5141\u8bb8\u51fd\u6570\u4ee5\u4e0d\u540c\u7684\u65b9\u5f0f\u5904\u7406\u5b57\u7b26\u4e32\u548c\u6570\u5b57\u7c7b\u578b\u3002<\/p>\n
2\u3002\u81ea\u5b9a\u4e49\u7c7b\u578b\u9632\u62a4\uff08\u662f\u5173\u952e\u5b57\uff09<\/strong><\/p>\n
\u7528\u4f8b<\/strong>\uff1a\u5bf9\u4e8e\u590d\u6742\u7684\u903b\u8f91\uff0c\u68c0\u67e5\u81ea\u5b9a\u4e49\u5f62\u72b6\u6216\u754c\u9762\u3002<\/p>\n
\u793a\u4f8b<\/strong>\uff1a<\/p>\n
 interface square {\n    side: number;\n  }\n  interface circle {\n    radius: number;\n  }\n\n  function issquare(shape: square | circle): shape is square {\n    return (shape as square).side !== undefined;\n  }\n\n  function calculatearea(shape: square | circle) {\n    if (issquare(shape)) {\n      return shape.side * shape.side;\n    } else {\n      return math.pi * shape.radius * shape.radius;\n    }\n  }\n<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u8bf4\u660e<\/strong>\uff1a\u81ea\u5b9a\u4e49\u7c7b\u578b\u9632\u62a4\u5141\u8bb8\u60a8\u5b9a\u4e49\u68c0\u67e5\u7279\u5b9a\u5c5e\u6027\u4ee5\u786e\u5b9a\u7c7b\u578b\u7684\u51fd\u6570\u3002\u5728\u8fd9\u91cc\uff0cissquare \u68c0\u67e5 side \u5c5e\u6027\u662f\u5426\u5b58\u5728\u3002<\/p>\n
3\u3002\u5728\u8fd0\u7b97\u7b26\u7c7b\u578b\u4fdd\u62a4\u4e2d<\/strong><\/p>\n
\u7528\u4f8b<\/strong>\uff1a\u68c0\u67e5\u5bf9\u8c61\u662f\u5426\u5177\u6709\u7279\u5b9a\u5c5e\u6027\u3002
\u793a\u4f8b<\/strong>\uff1a<\/p>\n
 interface Car {\n    drive(): void;\n  }\n  interface Boat {\n    sail(): void;\n  }\n\n  function move(vehicle: Car | Boat) {\n    if (\"drive\" in vehicle) {\n      vehicle.drive();\n    } else {\n      vehicle.sail();\n    }\n  }\n\n<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u8bf4\u660e<\/strong>\uff1ain \u8fd0\u7b97\u7b26\u68c0\u67e5\u5c5e\u6027\u662f\u5426\u5b58\u5728\uff0c\u5e2e\u52a9 typescript \u7406\u89e3\u7c7b\u578b\u5e76\u5141\u8bb8\u8bbf\u95ee\u76f8\u5173\u65b9\u6cd5\u3002<\/p>\n
\u7ed3\u8bba<\/strong><\/p>\n
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