{"id":203352,"date":"2025-05-22T11:16:54","date_gmt":"2025-05-22T03:16:54","guid":{"rendered":"https:\/\/server.hk\/cnblog\/203352\/"},"modified":"2025-05-22T11:16:54","modified_gmt":"2025-05-22T03:16:54","slug":"java-object%e8%bd%acdouble%ef%bc%8c%e5%a6%82%e4%bd%95%e4%bc%98%e9%9b%85%e5%9c%b0%e5%a4%84%e7%90%86null%e5%80%bc%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/203352\/","title":{"rendered":"Java Object\u8f6cDouble\uff0c\u5982\u4f55\u4f18\u96c5\u5730\u5904\u7406null\u503c\uff1f"},"content":{"rendered":"

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

Java Object\u8f6cDouble\uff0c\u5982\u4f55\u4f18\u96c5\u5730\u5904\u7406null\u503c\uff1f<\/h1>\n

\u5bf9\u4e8e\u4e00\u4e2a\u6587\u7ae0\u5f00\u53d1\u8005\u6765\u8bf4\uff0c\u7262\u56fa\u624e\u5b9e\u7684\u57fa\u7840\u662f\u5341\u5206\u91cd\u8981\u7684\uff0c\u5c31\u6765\u5e26\u5927\u5bb6\u4e00\u70b9\u70b9\u7684\u638c\u63e1\u57fa\u7840\u77e5\u8bc6\u70b9\u3002\u4eca\u5929\u672c\u7bc7\u6587\u7ae0\u5e26\u5927\u5bb6\u4e86\u89e3\u300aJava Object\u8f6cDouble\uff0c\u5982\u4f55\u4f18\u96c5\u5730\u5904\u7406null\u503c\uff1f\u300b\uff0c\u4e3b\u8981\u4ecb\u7ecd\u4e86\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u7684\u77e5\u8bc6\u79ef\u7d2f\u6709\u6240\u5e2e\u52a9\uff0c\u5feb\u70b9\u6536\u85cf\u8d77\u6765\u5427\uff0c\u5426\u5219\u9700\u8981\u65f6\u5c31\u627e\u4e0d\u5230\u4e86\uff01<\/p>\n

<\/p>\n

java object\u8f6cdouble\u5173\u4e8enull\u503c\u7684\u95ee\u9898\uff1a\u63a2\u8ba8\u66f4\u597d\u7684\u5b9e\u73b0\u65b9\u5f0f<\/strong><\/p>\n

java\u4e2d\u5e38\u89c1\u7684object\u8f6cdouble\u64cd\u4f5c\u4e2d\uff0c\u5f53object\u4e3anull\u65f6\uff0c\u4e0d\u540c\u8f6c\u6362\u65b9\u5f0f\u4f1a\u6709\u4e0d\u540c\u5904\u7406\u7ed3\u679c\u3002<\/p>\n

\u7b2c\u4e00\u79cd\u8f6c\u4e3adouble\uff1a<\/strong><\/p>\n

double d1 = (double) object;<\/pre>\n
\u6b64\u64cd\u4f5c\u5141\u8bb8object\u4e3anull\uff0c\u6b64\u65f6d1\u4e5f\u4f1a\u4e3anull\u3002\u4f46d1\u4e3anull\u65f6\uff0c\u5728\u4f7f\u7528d1\u8fdb\u884c\u8ba1\u7b97\u6216\u64cd\u4f5c\u65f6\uff0c\u53ef\u80fd\u4f1a\u51fa\u73b0\u7a7a\u6307\u9488\u5f02\u5e38\u3002<\/p>\n
\u7b2c\u4e8c\u79cd\u8f6c\u4e3adouble\uff1a<\/strong><\/p>\n
double d2 = object == null ? 0 : double.parsedouble(object.tostring());<\/pre>\n
\u6b64\u64cd\u4f5c\u9700\u8981\u5224\u65adobject\u662f\u5426\u4e3anull\uff0c\u5728object\u4e3anull\u65f6\u8d4b0\u503c\u3002\u8fd9\u79cd\u65b9\u5f0f\u53ef\u4ee5\u907f\u514d\u7a7a\u6307\u9488\u5f02\u5e38\uff0c\u4f46\u9700\u8981\u5728\u4ee3\u7801\u4e2d\u624b\u52a8\u5224\u65adnull\u503c\u3002<\/p>\n
\u66f4\u4f18\u7684\u5b9e\u73b0\u65b9\u5f0f\uff1a<\/strong><\/p>\n
\u63a8\u8350\u7684object\u8f6cdouble\u65b9\u5f0f\uff0c\u65e2\u53ef\u4ee5\u907f\u514d\u7a7a\u6307\u9488\u5f02\u5e38\uff0c\u53c8\u4e0d\u9700\u8981\u624b\u52a8\u5224\u65adnull\u503c\uff0c\u5982\u4e0b\uff1a<\/p>\n
double d1 = (double) (object == null ? 0d : object);\ndouble d2 = (double) (object == null ? 0d : object);<\/pre>\n
\u5de5\u5177\u7c7b\u65b9\u6cd5\uff1a<\/strong><\/p>\n
\u4e3a\u4e86\u7b80\u5316\u4ee3\u7801\uff0c\u53ef\u4ee5\u5728\u5de5\u5177\u7c7b\u4e2d\u5c01\u88c5\u6b64\u8f6c\u6362\u64cd\u4f5c\uff1a<\/p>\n
public static double parsedouble(object object) {\n    return (double) (object == null ? 0d : object);\n}<\/pre>\n
\u4f7f\u7528\u65f6\u76f4\u63a5\u8c03\u7528\u5de5\u5177\u7c7b\u65b9\u6cd5\uff1a<\/p>\n
Double d1 = parseDouble(object);\ndouble d2 = parseDouble(object);<\/pre>\n
\u603b\u7ed3\uff1a<\/strong><\/p>\n
\u63a8\u8350\u4f7f\u7528\u4e0a\u8ff0\u66f4\u4f18\u7684\u5b9e\u73b0\u65b9\u5f0f\u6216\u5de5\u5177\u7c7b\u65b9\u6cd5\uff0c\u65e2\u53ef\u4ee5\u907f\u514d\u7a7a\u6307\u9488\u5f02\u5e38\uff0c\u53c8\u65e0\u9700\u624b\u52a8\u5224\u65adnull\u503c\u3002<\/p>\n
\u4eca\u5929\u5173\u4e8e\u300aJava Object\u8f6cDouble\uff0c\u5982\u4f55\u4f18\u96c5\u5730\u5904\u7406null\u503c\uff1f\u300b\u7684\u5185\u5bb9\u4ecb\u7ecd\u5c31\u5230\u6b64\u7ed3\u675f\uff0c\u5982\u679c\u6709\u4ec0\u4e48\u7591\u95ee\u6216\u8005\u5efa\u8bae\uff0c\u53ef\u4ee5\u5728\u516c\u4f17\u53f7\u4e0b\u591a\u591a\u56de\u590d\u4ea4\u6d41\uff1b\u6587\u4e2d\u82e5\u6709\u4e0d\u6b63\u4e4b\u5904\uff0c\u4e5f\u5e0c\u671b\u56de\u590d\u7559\u8a00\u4ee5\u544a\u77e5\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
Java Object\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-203352","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203352","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=203352"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203352\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=203352"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=203352"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=203352"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}