{"id":6254,"date":"2024-07-10T06:52:18","date_gmt":"2024-07-09T22:52:18","guid":{"rendered":"https:\/\/t.n-years.com\/?p=6254"},"modified":"2024-07-10T06:54:10","modified_gmt":"2024-07-09T22:54:10","slug":"%e4%b8%ba%e4%bb%80%e4%b9%88%e4%b8%8d%e6%8e%a8%e8%8d%90%e4%bd%bf%e7%94%a8%e6%b5%ae%e7%82%b9%e6%95%b0%e6%9d%a5%e8%a1%a8%e7%a4%ba%e8%b4%a7%e5%b8%81","status":"publish","type":"post","link":"https:\/\/t.n-years.com\/?p=6254","title":{"rendered":"\u4e3a\u4ec0\u4e48\u4e0d\u63a8\u8350\u4f7f\u7528\u6d6e\u70b9\u6570\u6765\u8868\u793a\u8d27\u5e01"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\u975e\u539f\u521b\uff0cChatGPT\u95ee\u7b54<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u95ee\uff1a\u7ed9\u6211\u4ecb\u7ecd\u4e0b\u8fd9\u7bc7\u6587\u7ae0\u7684\u4e3b\u8981\u95ee\u9898\u548c\u539f\u56e0\uff1ahttps:\/\/stackoverflow.com\/questions\/3730019\/why-not-use-double-or-float-to-represent-currency<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u7bc7\u6587\u7ae0\u8ba8\u8bba\u4e86\u5728\u7f16\u7a0b\u4e2d\u4e3a\u4ec0\u4e48\u4e0d\u63a8\u8350\u4f7f\u7528\u6d6e\u70b9\u6570\uff08<code>float<\/code>\u6216<code>double<\/code>\uff09\u6765\u8868\u793a\u8d27\u5e01\u3002\u4e3b\u8981\u95ee\u9898\u548c\u539f\u56e0\u53ef\u4ee5\u603b\u7ed3\u5982\u4e0b\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7cbe\u5ea6\u95ee\u9898<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6d6e\u70b9\u6570\u5728\u8ba1\u7b97\u673a\u4e2d\u4ee5\u4e8c\u8fdb\u5236\u5f62\u5f0f\u8868\u793a\uff0c\u53ef\u80fd\u65e0\u6cd5\u7cbe\u786e\u5730\u8868\u793a\u67d0\u4e9b\u5341\u8fdb\u5236\u6570\u503c\uff0c\u7279\u522b\u662f\u5bf9\u4e8e\u8d27\u5e01\u8ba1\u7b97\u4e2d\u8981\u6c42\u7cbe\u786e\u5230\u5c0f\u6570\u70b9\u540e\u51e0\u4f4d\u7684\u60c5\u51b5\u3002\u8fd9\u53ef\u80fd\u5bfc\u81f4\u820d\u5165\u8bef\u5dee\u6216\u8ba1\u7b97\u9519\u8bef\uff0c\u4ece\u800c\u5f71\u54cd\u8d22\u52a1\u8ba1\u7b97\u7684\u51c6\u786e\u6027\u3002<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u820d\u5165\u9519\u8bef<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6d6e\u70b9\u6570\u5728\u8fdb\u884c\u57fa\u672c\u7b97\u672f\u8fd0\u7b97\uff08\u5982\u52a0\u6cd5\u548c\u4e58\u6cd5\uff09\u65f6\u53ef\u80fd\u4f1a\u4ea7\u751f\u5fae\u5c0f\u7684\u820d\u5165\u8bef\u5dee\u3002\u8fd9\u4e9b\u8bef\u5dee\u5728\u957f\u671f\u590d\u5408\u8ba1\u7b97\u4e2d\u53ef\u80fd\u4f1a\u79ef\u7d2f\uff0c\u5bfc\u81f4\u8ba1\u7b97\u7ed3\u679c\u4e0e\u9884\u671f\u503c\u4e0d\u7b26\u3002<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u53ef\u8bfb\u6027\u548c\u8c03\u8bd5\u56f0\u96be<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4f7f\u7528\u6d6e\u70b9\u6570\u8868\u793a\u8d27\u5e01\u53ef\u80fd\u4f7f\u5f97\u4ee3\u7801\u4e0d\u6613\u8bfb\u61c2\uff0c\u56e0\u4e3a\u4eba\u4eec\u4e0d\u4f1a\u671f\u671b\u770b\u5230\u5fae\u5c0f\u7684\u8bef\u5dee\u6216\u820d\u5165\u95ee\u9898\u3002\u8fd9\u53ef\u80fd\u589e\u52a0\u8c03\u8bd5\u4ee3\u7801\u65f6\u7684\u56f0\u96be\u548c\u590d\u6742\u6027\u3002<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u63a8\u8350\u7684\u66ff\u4ee3\u65b9\u6848<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u63a8\u8350\u4f7f\u7528\u6574\u6570\u7c7b\u578b\u6765\u8868\u793a\u8d27\u5e01\u7684\u6700\u5c0f\u5355\u4f4d\uff08\u5982\u7f8e\u5206\u6216\u6b27\u5206\uff09\uff0c\u5e76\u5728\u5fc5\u8981\u65f6\u8fdb\u884c\u9002\u5f53\u7684\u8f6c\u6362\u548c\u683c\u5f0f\u5316\u4ee5\u663e\u793a\u7ed9\u6700\u7ec8\u7528\u6237\u3002\u8fd9\u79cd\u65b9\u6cd5\u53ef\u4ee5\u907f\u514d\u6d6e\u70b9\u6570\u5e26\u6765\u7684\u7cbe\u5ea6\u95ee\u9898\uff0c\u5e76\u63d0\u9ad8\u4ee3\u7801\u7684\u53ef\u8bfb\u6027\u548c\u53ef\u7ef4\u62a4\u6027\u3002<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u56e0\u6b64\uff0c\u6587\u7ae0\u5efa\u8bae\u5728\u5904\u7406\u8d27\u5e01\u548c\u91d1\u878d\u6570\u636e\u65f6\uff0c\u5e94\u907f\u514d\u4f7f\u7528\u6d6e\u70b9\u6570\uff0c\u800c\u662f\u4f7f\u7528\u6574\u6570\u6765\u4fdd\u8bc1\u7cbe\u786e\u6027\u548c\u53ef\u9884\u6d4b\u6027\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u95ee\uff1a\u6df1\u5165\u8bb2\u4e0b\u539f\u56e0<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u6d89\u53ca\u5230\u8d27\u5e01\u548c\u91d1\u878d\u6570\u636e\u65f6\uff0c\u4e3a\u4ec0\u4e48\u4e0d\u63a8\u8350\u4f7f\u7528\u6d6e\u70b9\u6570\uff08<code>float<\/code>\u6216<code>double<\/code>\uff09\u662f\u4e00\u4e2a\u975e\u5e38\u91cd\u8981\u7684\u95ee\u9898\uff0c\u4e3b\u8981\u6d89\u53ca\u5230\u4ee5\u4e0b\u51e0\u4e2a\u65b9\u9762\u7684\u6df1\u5165\u8ba8\u8bba\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7cbe\u5ea6\u95ee\u9898<\/strong>\uff1a \u6d6e\u70b9\u6570\u5728\u8ba1\u7b97\u673a\u5185\u90e8\u4ee5\u4e8c\u8fdb\u5236\u5f62\u5f0f\u8868\u793a\uff0c\u800c\u5927\u591a\u6570\u8d27\u5e01\u5355\u4f4d\u662f\u4ee5\u5341\u8fdb\u5236\u5f62\u5f0f\u8868\u793a\u7684\uff0c\u4f8b\u5982\u7f8e\u5143\u7684\u5c0f\u6570\u4f4d\u548c\u6b27\u5143\u7684\u5206\u3002\u8fd9\u79cd\u4e8c\u8fdb\u5236\u8868\u793a\u53ef\u80fd\u5bfc\u81f4\u6d6e\u70b9\u6570\u65e0\u6cd5\u7cbe\u786e\u5730\u8868\u793a\u67d0\u4e9b\u5341\u8fdb\u5236\u6570\u503c\u3002\u4f8b\u5982\uff0c\u5341\u8fdb\u5236\u7684 <code>0.1<\/code> \u5728\u4e8c\u8fdb\u5236\u4e2d\u662f\u4e00\u4e2a\u65e0\u9650\u5faa\u73af\u7684\u5c0f\u6570 <code>0.0001100110011...<\/code>\u3002\u8fd9\u79cd\u7cbe\u5ea6\u95ee\u9898\u4f1a\u5bfc\u81f4\u5728\u8d27\u5e01\u8ba1\u7b97\u4e2d\u51fa\u73b0\u820d\u5165\u8bef\u5dee\uff0c\u4ece\u800c\u5f71\u54cd\u5230\u8d22\u52a1\u8ba1\u7b97\u7684\u51c6\u786e\u6027\u548c\u53ef\u9760\u6027\u3002 <strong>\u4f8b\u5b50\uff1a<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>   double total = 0.1 + 0.2; \/\/ \u7ed3\u679c\u4f1a\u662f\u4e00\u4e2a\u63a5\u8fd1 0.3 \u4f46\u4e0d\u662f\u7cbe\u786e\u7684 0.3<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u4e0a\u8ff0\u4f8b\u5b50\u4e2d\uff0c<code>0.1<\/code> \u548c <code>0.2<\/code> \u867d\u7136\u7b80\u5355\u7684\u5341\u8fdb\u5236\u6570\u503c\u770b\u8d77\u6765\u5f88\u76f4\u89c2\uff0c\u4f46\u662f\u5b83\u4eec\u5728\u6d6e\u70b9\u6570\u8868\u793a\u4e2d\u4f1a\u4ea7\u751f\u4e00\u4e2a\u5fae\u5c0f\u7684\u820d\u5165\u8bef\u5dee\uff0c\u5bfc\u81f4 <code>total<\/code> \u7684\u5b9e\u9645\u503c\u53ef\u80fd\u662f <code>0.30000000000000004<\/code>\uff0c\u800c\u4e0d\u662f\u9884\u671f\u7684 <code>0.3<\/code>\u3002\u5bf9\u4e8e\u8d27\u5e01\u8ba1\u7b97\u6765\u8bf4\uff0c\u8fd9\u79cd\u5fae\u5c0f\u7684\u5dee\u5f02\u662f\u4e0d\u53ef\u63a5\u53d7\u7684\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\" start=\"2\">\n<li><strong>\u820d\u5165\u9519\u8bef\u548c\u7d2f\u79ef\u95ee\u9898<\/strong>\uff1a \u5728\u957f\u671f\u590d\u5408\u8ba1\u7b97\u4e2d\uff0c\u6d6e\u70b9\u6570\u7684\u820d\u5165\u8bef\u5dee\u53ef\u80fd\u4f1a\u9010\u6b65\u7d2f\u79ef\uff0c\u5bfc\u81f4\u6700\u7ec8\u8ba1\u7b97\u7ed3\u679c\u4e0e\u9884\u671f\u503c\u76f8\u5dee\u751a\u8fdc\u3002\u4f8b\u5982\uff0c\u5982\u679c\u4e00\u4e2a\u91d1\u878d\u7cfb\u7edf\u8fdb\u884c\u4e86\u5927\u91cf\u7684\u52a0\u6cd5\u3001\u51cf\u6cd5\u548c\u4e58\u6cd5\u8fd0\u7b97\uff0c\u6bcf\u4e00\u6b65\u90fd\u53ef\u80fd\u4ea7\u751f\u5fae\u5c0f\u7684\u820d\u5165\u8bef\u5dee\uff0c\u8fd9\u4e9b\u8bef\u5dee\u4f1a\u5728\u957f\u65f6\u95f4\u5185\u7d2f\u79ef\u5e76\u4e14\u53d8\u5f97\u663e\u8457\u3002 <strong>\u4f8b\u5b50\uff1a<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>   double balance = 100.0;\n   double withdrawal = 0.1;\n   balance -= withdrawal; \/\/ \u53ef\u80fd\u4f1a\u5bfc\u81f4 balance \u53d8\u6210 99.89999999999999 \u800c\u4e0d\u662f\u9884\u671f\u7684 99.9<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u8ff0\u4f8b\u5b50\u4e2d\uff0c<code>balance -= withdrawal;<\/code> \u53ef\u80fd\u5bfc\u81f4 <code>balance<\/code> \u7684\u5b9e\u9645\u503c\u4e0d\u662f\u9884\u671f\u7684 <code>99.9<\/code>\uff0c\u800c\u662f\u4e00\u4e2a\u975e\u5e38\u63a5\u8fd1 <code>99.9<\/code> \u7684\u503c\uff0c\u4f8b\u5982 <code>99.89999999999999<\/code>\u3002\u867d\u7136\u770b\u4f3c\u5fae\u5c0f\u7684\u5dee\u5f02\uff0c\u4f46\u5728\u590d\u6742\u7684\u91d1\u878d\u5e94\u7528\u4e2d\uff0c\u8fd9\u79cd\u8bef\u5dee\u4f1a\u7d2f\u79ef\u5e76\u4ea7\u751f\u91cd\u5927\u5f71\u54cd\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\" start=\"3\">\n<li><strong>\u53ef\u8bfb\u6027\u548c\u8c03\u8bd5\u56f0\u96be<\/strong>\uff1a \u4f7f\u7528\u6d6e\u70b9\u6570\u6765\u8868\u793a\u8d27\u5e01\u53ef\u80fd\u4f1a\u4f7f\u4ee3\u7801\u53d8\u5f97\u4e0d\u6613\u8bfb\u61c2\u548c\u8c03\u8bd5\uff0c\u56e0\u4e3a\u4eba\u4eec\u901a\u5e38\u4e0d\u4f1a\u671f\u671b\u770b\u5230\u5fae\u5c0f\u7684\u820d\u5165\u8bef\u5dee\u6216\u4e0d\u7cbe\u786e\u7684\u8ba1\u7b97\u7ed3\u679c\u3002\u8fd9\u53ef\u80fd\u5bfc\u81f4\u5f00\u53d1\u4eba\u5458\u96be\u4ee5\u7406\u89e3\u548c\u6392\u67e5\u4ee3\u7801\u4e2d\u7684\u9519\u8bef\uff0c\u7279\u522b\u662f\u5728\u6d89\u53ca\u590d\u6742\u91d1\u878d\u903b\u8f91\u6216\u5927\u91cf\u8ba1\u7b97\u7684\u60c5\u51b5\u4e0b\u3002<\/li>\n\n\n\n<li><strong>\u63a8\u8350\u7684\u66ff\u4ee3\u65b9\u6848<\/strong>\uff1a \u4e3a\u4e86\u907f\u514d\u4e0a\u8ff0\u95ee\u9898\uff0c\u63a8\u8350\u4f7f\u7528\u6574\u6570\u7c7b\u578b\u6765\u8868\u793a\u8d27\u5e01\u7684\u6700\u5c0f\u5355\u4f4d\uff08\u4f8b\u5982\u7f8e\u5206\u6216\u6b27\u5206\uff09\uff0c\u800c\u4e0d\u662f\u4f7f\u7528\u6d6e\u70b9\u6570\u3002\u8fd9\u79cd\u505a\u6cd5\u79f0\u4e3a\"\u8d27\u5e01\u5206\u79bb\"\uff08Currency separation\uff09\uff0c\u5373\u5c06\u6240\u6709\u8d27\u5e01\u6570\u503c\u8f6c\u6362\u4e3a\u6574\u6570\u5904\u7406\uff0c\u4ee5\u907f\u514d\u7cbe\u5ea6\u95ee\u9898\u548c\u820d\u5165\u8bef\u5dee\u3002\u4f8b\u5982\uff0c\u5bf9\u4e8e\u7f8e\u5143\uff0c\u5c06\u91d1\u989d\u4ee5\u6574\u6570\u7f8e\u5206\u7684\u5f62\u5f0f\u5b58\u50a8\u548c\u8ba1\u7b97\uff0c\u800c\u5728\u9700\u8981\u663e\u793a\u7ed9\u7528\u6237\u65f6\uff0c\u518d\u8fdb\u884c\u9002\u5f53\u7684\u8f6c\u6362\u548c\u683c\u5f0f\u5316\u3002 <strong>\u4f8b\u5b50\uff1a<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>   int amountInCents = 1000; \/\/ \u4ee3\u8868 $10.00<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u7528\u6574\u6570\u6765\u8868\u793a\u8d27\u5e01\u4e0d\u4ec5\u53ef\u4ee5\u786e\u4fdd\u7cbe\u786e\u6027\uff0c\u8fd8\u80fd\u63d0\u9ad8\u4ee3\u7801\u7684\u53ef\u8bfb\u6027\u548c\u53ef\u7ef4\u62a4\u6027\uff0c\u56e0\u4e3a\u5b83\u6d88\u9664\u4e86\u6d6e\u70b9\u6570\u53ef\u80fd\u5e26\u6765\u7684\u590d\u6742\u6027\u548c\u4e0d\u786e\u5b9a\u6027\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7efc\u4e0a\u6240\u8ff0\uff0c\u907f\u514d\u4f7f\u7528\u6d6e\u70b9\u6570\u6765\u5904\u7406\u8d27\u5e01\u548c\u91d1\u878d\u6570\u636e\u662f\u4e00\u4e2a\u57fa\u4e8e\u6570\u503c\u7cbe\u5ea6\u3001\u820d\u5165\u8bef\u5dee\u3001\u53ef\u8bfb\u6027\u548c\u8c03\u8bd5\u65b9\u9762\u7684\u660e\u667a\u9009\u62e9\u3002\u901a\u8fc7\u4f7f\u7528\u6574\u6570\u7c7b\u578b\u548c\u9002\u5f53\u7684\u8f6c\u6362\u7b56\u7565\uff0c\u53ef\u4ee5\u786e\u4fdd\u5728\u91d1\u878d\u8ba1\u7b97\u4e2d\u83b7\u5f97\u53ef\u9760\u548c\u7cbe\u786e\u7684\u7ed3\u679c\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u975e\u539f\u521b\uff0cChatGPT\u95ee\u7b54 \u95ee\uff1a\u7ed9\u6211\u4ecb\u7ecd\u4e0b\u8fd9\u7bc7\u6587\u7ae0\u7684\u4e3b\u8981\u95ee\u9898\u548c\u539f\u56e0\uff1ahttps:\/\/stackoverflow&#8230; <\/p>\n<div class=\"read-more navbutton\"><a href=\"https:\/\/t.n-years.com\/?p=6254\">\u9605\u8bfb\u66f4\u591a<i class=\"fa 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