{"id":205296,"date":"2025-05-29T17:48:47","date_gmt":"2025-05-29T09:48:47","guid":{"rendered":"https:\/\/server.hk\/cnblog\/205296\/"},"modified":"2025-05-29T17:48:47","modified_gmt":"2025-05-29T09:48:47","slug":"python-%e7%b1%bb%e6%96%b9%e6%b3%95%e8%b0%83%e7%94%a8%e4%b8%ad%e7%9a%84%e9%99%b7%e9%98%b1%ef%bc%9a%e5%a6%82%e4%bd%95%e7%9b%b4%e6%8e%a5%e8%b0%83%e7%94%a8%e5%86%85%e9%83%a8%e5%af%b9%e8%b1%a1%e7%9a%84-__s","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/205296\/","title":{"rendered":"Python \u7c7b\u65b9\u6cd5\u8c03\u7528\u4e2d\u7684\u9677\u9631\uff1a\u5982\u4f55\u76f4\u63a5\u8c03\u7528\u5185\u90e8\u5bf9\u8c61\u7684 __str__ \u65b9\u6cd5\uff1f"},"content":{"rendered":"

<\/b> <\/p>\n

Python \u7c7b\u65b9\u6cd5\u8c03\u7528\u4e2d\u7684\u9677\u9631\uff1a\u5982\u4f55\u76f4\u63a5\u8c03\u7528\u5185\u90e8\u5bf9\u8c61\u7684 __str__ \u65b9\u6cd5\uff1f<\/h1>\n

\u600e\u4e48\u5165\u95e8\u6587\u7ae0\u7f16\u7a0b\uff1f\u9700\u8981\u5b66\u4e60\u54ea\u4e9b\u77e5\u8bc6\u70b9\uff1f\u8fd9\u662f\u65b0\u624b\u4eec\u521a\u63a5\u89e6\u7f16\u7a0b\u65f6\u5e38\u89c1\u7684\u95ee\u9898\uff1b\u4e0b\u9762\u5c31\u6765\u7ed9\u5927\u5bb6\u6574\u7406\u5206\u4eab\u4e00\u4e9b\u77e5\u8bc6\u70b9\uff0c\u5e0c\u671b\u80fd\u591f\u7ed9\u521d\u5b66\u8005\u4e00\u4e9b\u5e2e\u52a9\u3002\u672c\u7bc7\u6587\u7ae0\u5c31\u6765\u4ecb\u7ecd\u300aPython \u7c7b\u65b9\u6cd5\u8c03\u7528\u4e2d\u7684\u9677\u9631\uff1a\u5982\u4f55\u76f4\u63a5\u8c03\u7528\u5185\u90e8\u5bf9\u8c61\u7684 __str__ \u65b9\u6cd5\uff1f\u300b\uff0c\u6d89\u53ca\u5230\uff0c\u6709\u9700\u8981\u7684\u53ef\u4ee5\u6536\u85cf\u4e00\u4e0b<\/p>\n

<\/p>\n

python \u7c7b\u65b9\u6cd5\u4f7f\u7528\u65b9\u6cd5<\/strong><\/p>\n

\u5728 python \u4e2d\uff0c\u5f53\u4f60\u5e0c\u671b\u8c03\u7528\u4e00\u4e2a\u7c7b\u7684\u65b9\u6cd5\u65f6\uff0c\u901a\u5e38\u53ef\u4ee5\u4f7f\u7528\u8be5\u7c7b\u540d\u540e\u8ddf\u70b9\u53f7\u64cd\u4f5c\u7b26\uff08. \uff09\uff0c\u7136\u540e\u662f\u65b9\u6cd5\u540d\u3002\u7136\u800c\uff0c\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c\u4f60\u53ef\u80fd\u5e0c\u671b\u76f4\u63a5\u8c03\u7528\u7c7b\u7684\u5c5e\u6027\uff0c\u800c\u4e0d\u662f\u65b9\u6cd5\u3002\u672c\u6587\u5c06\u63a2\u8ba8\u8fd9\u4e2a\u95ee\u9898\uff0c\u5e76\u63d0\u4f9b\u4e00\u79cd\u89e3\u51b3\u65b9\u6cd5\u3002<\/p>\n

\u5047\u8bbe\u4f60\u7f16\u5199\u4e86\u4ee5\u4e0b\u4ee3\u7801\uff1a<\/p>\n

class pointer:\n\n    def __init__(self, value=none):\n        self.__interior = true\n        self.__value = value\n        self.__interior = false\n\n    def __getattribute__(self, item):\n        if super().__getattribute__('_pointer__interior'):\n            return super().__getattribute__(item)\n        if item == '__value' or item == '_pointer__value':\n            return super().__getattribute__('_pointer__value')\n        return getattr(super().__getattribute__('_pointer__value'), item)\n\n    def __setattr__(self, item, value):\n        if item == '_pointer__interior':\n            super().__setattr__('_pointer__interior', value)\n        elif super().__getattribute__('_pointer__interior'):\n            super().__setattr__(item, value)\n        else:\n            if item == '__value' or item == '_pointer__value':\n                super().__setattr__('_pointer__value', value)\n            else:\n                setattr(super().__getattribute__('__value'), item, value)\n\nclass strpointer(pointer, str):\n  pass<\/pre>\n
\u8fd9\u4e2a\u7c7b\u5177\u6709\u4e00\u4e2a __getattribute__ \u65b9\u6cd5\uff0c\u5b83\u6839\u636e\u5c5e\u6027\u540d\u6765\u786e\u5b9a\u662f\u8c03\u7528\u5f53\u524d\u7c7b\u7684\u5c5e\u6027\u8fd8\u662f\u5185\u90e8\u5b58\u50a8\u7684 str \u5bf9\u8c61\u7684\u5c5e\u6027\u3002<\/p>\n
\u73b0\u5728\uff0c\u60f3\u8c61\u4e00\u4e0b\u4f60\u60f3\u8c03\u7528 str \u7c7b\u7684 __str__ \u65b9\u6cd5\uff0c\u800c\u4e0d\u662f pointer \u7684\u540c\u540d\u65b9\u6cd5\u3002\u6309\u7167\u5e38\u89c4\u65b9\u5f0f\uff0c\u4f60\u4f1a\u8fd9\u6837\u505a\uff1a<\/p>\n
ptr = strpointer('a')\nprint(ptr.__str__)<\/pre>\n
\u4f46\u662f\uff0c\u8fd9\u4f1a\u4ea7\u751f\u5982\u4e0b\u8f93\u51fa\uff1a<\/p>\n
<method-wrapper '__str__' of str object at 0x0000000002572800><\/pre>\n
\u8fd9\u8868\u660e __str__ \u65b9\u6cd5\u5b9e\u9645\u4e0a\u5e76\u672a\u88ab\u8c03\u7528\u3002\u8fd9\u662f\u56e0\u4e3a print \u51fd\u6570\u81ea\u52a8\u5c06\u4f20\u9012\u7ed9\u5b83\u7684\u4efb\u4f55\u5bf9\u8c61\u8f6c\u6362\u4e3a\u5b57\u7b26\u4e32\u3002\u5b83\u901a\u8fc7\u8c03\u7528 type(object).__str__(object) \u6765\u6267\u884c\u6b64\u8f6c\u6362\u3002<\/p>\n
\u8981\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff0c\u4f60\u9700\u8981\u4e3a pointer \u7c7b\u76f4\u63a5\u5b9e\u73b0 __str__ \u65b9\u6cd5\u3002\u8fd9\u6837\uff0c\u5f53\u4f60\u8c03\u7528 print(ptr) \u65f6\uff0c\u5c06\u8c03\u7528 pointer \u7c7b\u7684 __str__ \u65b9\u6cd5\uff0c\u800c\u4e0d\u662f str \u7c7b\u7684 __str__ \u65b9\u6cd5\u3002<\/p>\n
\u4fee\u6539\u540e\u7684\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
class pointer:\n\n    # ... \u5176\u4ed6\u4ee3\u7801...\n\n    def __str__(self):\n        return super().__getattribute__('_pointer__value')<\/pre>\n
\u73b0\u5728\uff0c\u5f53\u4f60\u8c03\u7528 print(ptr) \u65f6\uff0c\u8f93\u51fa\u5c06\u662f\uff1a<\/p>\n
a<\/pre>\n
\u8fd9\u8868\u660e pointer \u7c7b\u7684 __str__ \u65b9\u6cd5\u5df2\u88ab\u6210\u529f\u8c03\u7528\u3002<\/p>\n
\u4eca\u5929\u5e26\u5927\u5bb6\u4e86\u89e3\u4e86\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u5e0c\u671b\u5bf9\u4f60\u6709\u6240\u5e2e\u52a9\uff1b\u5173\u4e8e\u6587\u7ae0\u7684\u6280\u672f\u77e5\u8bc6\u6211\u4eec\u4f1a\u4e00\u70b9\u70b9\u6df1\u5165\u4ecb\u7ecd\uff0c\u6b22\u8fce\u5927\u5bb6\u5173\u6ce8\u516c\u4f17\u53f7\uff0c\u4e00\u8d77\u5b66\u4e60\u7f16\u7a0b~<\/p>\n","protected":false},"excerpt":{"rendered":"
Python \u7c7b\u65b9\u6cd5\u8c03\u7528\u4e2d\u7684\u9677\u9631...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-205296","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/205296","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=205296"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/205296\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=205296"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=205296"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=205296"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}