{"id":4826,"date":"2023-01-05T10:37:27","date_gmt":"2023-01-05T02:37:27","guid":{"rendered":"https:\/\/badgameshow.com\/steven\/?p=4826"},"modified":"2023-01-05T10:37:27","modified_gmt":"2023-01-05T02:37:27","slug":"%e4%ba%86%e8%a7%a3typescript%e7%b1%bb%e5%9e%8b%e5%ae%88%e5%8d%ab%e7%9a%84%e5%8a%9f%e8%83%bd%e8%88%87%e5%84%aa%e9%bb%9e","status":"publish","type":"post","link":"https:\/\/badgameshow.com\/steven\/typescript\/%e4%ba%86%e8%a7%a3typescript%e7%b1%bb%e5%9e%8b%e5%ae%88%e5%8d%ab%e7%9a%84%e5%8a%9f%e8%83%bd%e8%88%87%e5%84%aa%e9%bb%9e\/","title":{"rendered":"\u4e86\u89e3TypeScript\u7c7b\u578b\u5b88\u536b\u7684\u529f\u80fd\u8207\u512a\u9ede"},"content":{"rendered":"<p><meta name=\"keywords\" content=\"TypeScript, Type Guard\"><\/p>\n<h1>TypeScript \u7c7b\u578b\u5b88\u536b(type guard)<\/h1>\n<p>TypeScript \u7c7b\u578b\u5b88\u536b(type guard)\u662f\u4e00\u7a2e\u6280\u8853\uff0c\u53ef\u4ee5\u5728\u7a0b\u5f0f\u78bc\u4e2d\u6aa2\u67e5\u548c\u78ba\u8a8d\u8b8a\u6578\u7684\u985e\u578b\u3002\u5b83\u53ef\u4ee5\u8b93\u958b\u767c\u8005\u5728\u7a0b\u5f0f\u78bc\u4e2d\u66f4\u5bb9\u6613\u5730\u6aa2\u67e5\u548c\u78ba\u8a8d\u8b8a\u6578\u7684\u985e\u578b\uff0c\u4ee5\u78ba\u4fdd\u7a0b\u5f0f\u78bc\u7684\u6b63\u78ba\u6027\u3002<\/p>\n<p>TypeScript \u7c7b\u578b\u5b88\u536b\u662f\u4e00\u7a2e\u6280\u8853\uff0c\u53ef\u4ee5\u5728\u7a0b\u5f0f\u78bc\u4e2d\u6aa2\u67e5\u548c\u78ba\u8a8d\u8b8a\u6578\u7684\u985e\u578b\u3002\u5b83\u53ef\u4ee5\u8b93\u958b\u767c\u8005\u5728\u7a0b\u5f0f\u78bc\u4e2d\u66f4\u5bb9\u6613\u5730\u6aa2\u67e5\u548c\u78ba\u8a8d\u8b8a\u6578\u7684\u985e\u578b\uff0c\u4ee5\u78ba\u4fdd\u7a0b\u5f0f\u78bc\u7684\u6b63\u78ba\u6027\u3002<\/p>\n<p><!--more--><\/p>\n<p>TypeScript \u7c7b\u578b\u5b88\u536b\u53ef\u4ee5\u8b93\u958b\u767c\u8005\u5728\u7a0b\u5f0f\u78bc\u4e2d\u66f4\u5bb9\u6613\u5730\u6aa2\u67e5\u548c\u78ba\u8a8d\u8b8a\u6578\u7684\u985e\u578b\uff0c\u4ee5\u78ba\u4fdd\u7a0b\u5f0f\u78bc\u7684\u6b63\u78ba\u6027\u3002\u5b83\u53ef\u4ee5\u8b93\u958b\u767c\u8005\u5728\u7a0b\u5f0f\u78bc\u4e2d\u66f4\u5bb9\u6613\u5730\u6aa2\u67e5\u548c\u78ba\u8a8d\u8b8a\u6578\u7684\u985e\u578b\uff0c\u4ee5\u78ba\u4fdd\u7a0b\u5f0f\u78bc\u7684\u6b63\u78ba\u6027\u3002<\/p>\n<p>TypeScript \u7c7b\u578b\u5b88\u536b\u53ef\u4ee5\u8b93\u958b\u767c\u8005\u5728\u7a0b\u5f0f\u78bc\u4e2d\u66f4\u5bb9\u6613\u5730\u6aa2\u67e5\u548c\u78ba\u8a8d\u8b8a\u6578\u7684\u985e\u578b\uff0c\u4ee5\u78ba\u4fdd\u7a0b\u5f0f\u78bc\u7684\u6b63\u78ba\u6027\u3002\u8209\u4f8b\u4f86\u8aaa\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u8b8a\u6578\uff0c\u5b83\u53ef\u4ee5\u662f\u5b57\u4e32\u6216\u6578\u5b57\uff0c\u6211\u5011\u53ef\u4ee5\u4f7f\u7528 TypeScript 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'number') {\n    \/\/ param is a number\n  }\n}\n<\/pre>\n<p>\u5728\u4e0a\u9762\u7684\u7a0b\u5f0f\u78bc\u4e2d\uff0c\u6211\u5011\u4f7f\u7528\u4e86 TypeScript \u7c7b\u578b\u5b88\u536b\u4f86\u6aa2\u67e5\u51fd\u6578 myFunc \u7684\u53c3\u6578\u985e\u578b\uff0c\u4ee5\u78ba\u4fdd\u51fd\u6578\u7684\u6b63\u78ba\u6027\u3002<\/p>\n<p>\u7e3d\u7d50\u4f86\u8aaa\uff0cTypeScript 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