{"id":203509,"date":"2025-05-22T09:35:53","date_gmt":"2025-05-22T01:35:53","guid":{"rendered":"https:\/\/server.hk\/cnblog\/203509\/"},"modified":"2025-05-22T09:35:53","modified_gmt":"2025-05-22T01:35:53","slug":"java%e4%b8%adobject%e8%bd%acdoubledouble%e6%97%b6%e5%a6%82%e4%bd%95%e5%a4%84%e7%90%86null%e5%80%bc%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/203509\/","title":{"rendered":"Java\u4e2dObject\u8f6cDouble(double)\u65f6\u5982\u4f55\u5904\u7406null\u503c\uff1f"},"content":{"rendered":"

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

Java\u4e2dObject\u8f6cDouble(double)\u65f6\u5982\u4f55\u5904\u7406null\u503c\uff1f<\/h1>\n

\u6700\u8fd1\u53d1\u73b0\u4e0d\u5c11\u5c0f\u4f19\u4f34\u90fd\u5bf9\u6587\u7ae0<\/span>\u5f88\u611f\u5174\u8da3\uff0c\u6240\u4ee5\u4eca\u5929\u7ee7\u7eed\u7ed9\u5927\u5bb6\u4ecb\u7ecd\u6587\u7ae0<\/span>\u76f8\u5173\u7684\u77e5\u8bc6\uff0c\u672c\u6587\u300aJava\u4e2dObject\u8f6cDouble(double)\u65f6\u5982\u4f55\u5904\u7406null\u503c\uff1f\u300b<\/span>\u4e3b\u8981\u5185\u5bb9\u6d89\u53ca\u5230<\/span>\u7b49\u7b49\u77e5\u8bc6\u70b9\uff0c\u5e0c\u671b\u80fd\u5e2e\u5230\u4f60\uff01\u5f53\u7136\u5982\u679c\u9605\u8bfb\u672c\u6587\u65f6\u5b58\u5728\u4e0d\u540c\u60f3\u6cd5\uff0c\u53ef\u4ee5\u5728\u8bc4\u8bba\u4e2d\u8868\u8fbe\uff0c\u4f46\u662f\u8bf7\u52ff\u4f7f\u7528\u8fc7\u6fc0\u7684\u63aa\u8f9e~<\/p>\n

<\/p>\n

java object\u8f6cdouble(double)\u65f6\u5982\u4f55\u5904\u7406null\u503c<\/strong><\/p>\n

\u5728java\u4e2d\uff0cdouble\u7c7b\u662fdouble\u7684\u57fa\u672c\u7c7b\u578b\u5c01\u88c5\uff0c\u5141\u8bb8\u4f7f\u7528null\u3002\u56e0\u6b64\uff0c\u5728\u5c06object\u8f6c\u6362\u4e3adouble\u65f6\uff0c\u9700\u8981\u6ce8\u610fnull\u503c\u7684\u60c5\u51b5\u3002<\/p>\n

\u4ee5\u4e0b\u662f\u4e24\u79cd\u5e38\u89c1\u7684\u8f6c\u6362\u65b9\u5f0f\uff1a<\/p>\n

1. \u8f6c\u4e3adouble<\/strong><\/p>\n

double d1 = (double) object;<\/pre>\n
\u8fd9\u79cd\u65b9\u5f0f\u76f4\u63a5\u5c06object\u8f6c\u6362\u4e3adouble\uff0c\u5f53object\u4e3anull\u65f6\uff0cd1\u4e5f\u4e3anull\u3002\u5982\u679c\u540e\u7eed\u9700\u8981\u4f7f\u7528d1\u7684\u503c\u8fdb\u884c\u8ba1\u7b97\uff0c\u4f1a\u5f15\u53d1\u7a7a\u6307\u9488\u5f02\u5e38\u3002<\/p>\n
2. \u8f6c\u4e3adouble<\/strong><\/p>\n
double d2 = (double) object;<\/pre>\n
\u8fd9\u79cd\u65b9\u5f0f\u76f4\u63a5\u5c06object\u8f6c\u6362\u4e3adouble\u57fa\u672c\u7c7b\u578b\u3002\u4f46\u662f\uff0c\u7531\u4e8edouble\u4e0d\u5141\u8bb8null\u503c\uff0c\u5f53object\u4e3anull\u65f6\u4f1a\u5f15\u53d1\u7f16\u8bd1\u9519\u8bef\u3002<\/p>\n
\u66f4\u4f73\u7684\u5b9e\u73b0\u65b9\u5f0f<\/strong><\/p>\n
\u4e3a\u4e86\u907f\u514d\u4ee5\u4e0a\u4e24\u79cd\u65b9\u5f0f\u7684\u7f3a\u70b9\uff0c\u53ef\u4ee5\u91c7\u7528\u4ee5\u4e0b\u66f4\u4f73\u7684\u5b9e\u73b0\u65b9\u5f0f\uff1a<\/p>\n
double d1 = (double) (object == null ? 0d: object);\ndouble d2 = (double)(object == null ? 0d: object);<\/pre>\n
\u8fd9\u79cd\u65b9\u5f0f\u5728\u5224\u65adobject\u662f\u5426\u4e3anull\u540e\uff0c\u518d\u8fdb\u884c\u8f6c\u6362\u3002\u5bf9\u4e8edouble\uff0c\u5982\u679cobject\u4e3anull\uff0c\u5219\u8d4b\u503c\u4e3a0d\uff0c\u907f\u514d\u7a7a\u6307\u9488\u5f02\u5e38\uff1b\u5bf9\u4e8edouble\uff0c\u5982\u679cobject\u4e3anull\uff0c\u540c\u6837\u8d4b\u503c\u4e3a0d\uff0c\u907f\u514d\u7f16\u8bd1\u9519\u8bef\u3002<\/p>\n
\u901a\u5e38\uff0c\u8fd9\u79cd\u7c7b\u578b\u7684\u8f6c\u6362\u4f1a\u7f16\u5199\u5728\u5de5\u5177\u7c7b\u4e2d\uff0c\u65b9\u4fbf\u8c03\u7528\uff1a<\/p>\n
public static double parsedouble(object object){\n    return (double)(object == null ? 0d: object);\n}<\/pre>\n
\u4f7f\u7528\u65f6\uff0c\u76f4\u63a5\u8c03\u7528\u8be5\u65b9\u6cd5\u5373\u53ef\uff1a<\/p>\n
Double d1 = parseDouble(object);\ndouble d2 = parseDouble(object);<\/pre>\n
\u672c\u7bc7\u5173\u4e8e\u300aJava\u4e2dObject\u8f6cDouble(double)\u65f6\u5982\u4f55\u5904\u7406null\u503c\uff1f\u300b\u7684\u4ecb\u7ecd\u5c31\u5230\u6b64\u7ed3\u675f\u5566\uff0c\u4f46\u662f\u5b66\u65e0\u6b62\u5883\uff0c\u60f3\u8981\u4e86\u89e3\u5b66\u4e60\u66f4\u591a\u5173\u4e8e\u6587\u7ae0\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u8bf7\u5173\u6ce8\u516c\u4f17\u53f7\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
Java\u4e2dObject\u8f6cDoub...<\/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-203509","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203509","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=203509"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203509\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=203509"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=203509"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=203509"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}