{"id":178142,"date":"2022-04-15T01:47:33","date_gmt":"2022-04-14T17:47:33","guid":{"rendered":"http:\/\/www.idc.net\/help\/178142\/"},"modified":"2022-04-15T01:47:33","modified_gmt":"2022-04-14T17:47:33","slug":"%e5%90%8e%e6%b5%aa%e4%ba%91python%e6%95%99%e7%a8%8b%ef%bc%9apython%e7%9a%84eval%e5%87%bd%e6%95%b0%e4%bd%9c%e7%94%a8","status":"publish","type":"post","link":"https:\/\/idc.net\/help\/178142\/","title":{"rendered":"\u540e\u6d6a\u4e91Python\u6559\u7a0b\uff1apython\u7684eval\u51fd\u6570\u4f5c\u7528"},"content":{"rendered":"

<\/p>\n

eval(str)\u51fd\u6570\u5f88\u5f3a\u5927\uff0c\u5b98\u65b9\u89e3\u91ca\u4e3a\uff1a\u5c06\u5b57\u7b26\u4e32str\u5f53\u6210\u6709\u6548\u7684\u8868\u8fbe\u5f0f\u6765\u6c42\u503c\u5e76\u8fd4\u56de\u8ba1\u7b97\u7ed3\u679c\u3002<\/strong>\u6240\u4ee5\uff0c\u7ed3\u5408math\u5f53\u6210\u4e00\u4e2a\u8ba1\u7b97\u5668\u5f88\u597d\u7528\u3002<\/p>\n

eval()\u51fd\u6570\u5e38\u89c1\u4f5c\u7528\u6709\uff1a <\/strong><\/p>\n

1\u3001\u8ba1\u7b97\u5b57\u7b26\u4e32\u4e2d\u6709\u6548\u7684\u8868\u8fbe\u5f0f\uff0c\u5e76\u8fd4\u56de\u7ed3\u679c<\/strong><\/p>\n

>>> eval('pow(2,2)')4\n>>> eval('2 + 2')4\n>>> eval(\"n + 4\")85<\/pre>\n
2\u3001\u5c06\u5b57\u7b26\u4e32\u8f6c\u6210\u76f8\u5e94\u7684\u5bf9\u8c61\uff08\u5982list\u3001tuple\u3001dict\u548cstring\u4e4b\u95f4\u7684\u8f6c\u6362\uff09<\/strong><\/p>\n
>>> a = \"[[1,2], [3,4], [5,6], [7,8], [9,0]]\"\n>>> b = eval(a)\n>>> b\n[[1, 2], [3, 4], [5, 6], [7, 8], [9, 0]]\n>>> a = \"{1:'xx',2:'yy'}\"\n>>> c = eval(a)\n>>> c\n{1: 'xx', 2: 'yy'}\n>>> a = \"(1,2,3,4)\"\n>>> d = eval(a)\n>>> d\n(1, 2, 3, 4)<\/pre>\n
3\u3001\u5c06\u5229\u7528\u53cd\u5f15\u53f7\u8f6c\u6362\u7684\u5b57\u7b26\u4e32\u518d\u53cd\u8f6c\u56de\u5bf9\u8c61<\/strong><\/p>\n
>>> list1 = [1,2,3,4,5]\n>>> `list1`\n'[1, 2, 3, 4, 5]'\n>>> type(`list1`)\n<type 'str'>\n>>> type(eval(`list1`))\n<type 'list'>\n>>> a = eval(`list1`)\n>>> a\n[1, 2, 3, 4, 5]<\/pre>\n","protected":false},"excerpt":{"rendered":"
eval(str)\u51fd\u6570\u5f88\u5f3a\u5927\uff0c\u5b98\u65b9\u89e3\u91ca\u4e3a\uff1a\u5c06\u5b57\u7b26\u4e32str\u5f53\u6210\u6709\u6548\u7684\u8868\u8fbe\u5f0f\u6765\u6c42\u503c\u5e76\u8fd4\u56de\u8ba1\u7b97\u7ed3\u679c\u3002\u6240\u4ee5\uff0c\u7ed3\u5408mat […]<\/p>\n","protected":false},"author":1,"featured_media":178143,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[182397],"tags":[],"class_list":["post-178142","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-python"],"_links":{"self":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts\/178142","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/comments?post=178142"}],"version-history":[{"count":0,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts\/178142\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/media\/178143"}],"wp:attachment":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/media?parent=178142"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/categories?post=178142"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/tags?post=178142"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}