{"id":35312,"date":"2024-11-26T17:00:49","date_gmt":"2024-11-26T09:00:49","guid":{"rendered":"https:\/\/fwq.ai\/blog\/35312\/"},"modified":"2024-11-26T17:00:49","modified_gmt":"2024-11-26T09:00:49","slug":"java%e6%80%8e%e4%b9%88%e6%8a%8alist%e8%bd%ac%e6%8d%a2%e6%88%90%e6%95%b0%e7%bb%84","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/35312\/","title":{"rendered":"java\u600e\u4e48\u628alist\u8f6c\u6362\u6210\u6570\u7ec4"},"content":{"rendered":"<blockquote><p>\n  java \u4e2d\u5c06 list \u8f6c\u6362\u4e3a\u6570\u7ec4\u7684\u65b9\u6cd5\uff1a1. \u4f7f\u7528 toarray() \u65b9\u6cd5\u5c06 list \u8f6c\u6362\u4e3a\u6307\u5b9a\u7c7b\u578b\u7684\u6570\u7ec4\uff1b2. \u4f7f\u7528 for-each \u5faa\u73af\u8fed\u4ee3 list \u5e76\u5c06\u6bcf\u4e2a\u5143\u7d20\u590d\u5236\u5230\u6570\u7ec4\u4e2d\u3002\n<\/p><\/blockquote>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/202411\/04\/2024110400031817497.jpg\" class=\"aligncenter\" title=\"java\u600e\u4e48\u628alist\u8f6c\u6362\u6210\u6570\u7ec4\u63d2\u56fe\" alt=\"java\u600e\u4e48\u628alist\u8f6c\u6362\u6210\u6570\u7ec4\u63d2\u56fe\" \/><\/p>\n<p><strong>\u5982\u4f55\u5c06 Java List \u8f6c\u6362\u4e3a\u6570\u7ec4<\/strong><\/p>\n<p>\u5728 Java \u4e2d\uff0c\u5c06 List \u8f6c\u6362\u4e3a\u6570\u7ec4\u6709\u4e24\u79cd\u5e38\u89c1\u7684\u65b9\u6cd5\uff1a<\/p>\n<p><strong>1. \u4f7f\u7528 toArray() \u65b9\u6cd5<\/strong><\/p>\n<p>toArray() \u65b9\u6cd5\u53ef\u4ee5\u5c06 List \u8f6c\u6362\u4e3a\u6307\u5b9a\u7c7b\u578b T \u7684\u6570\u7ec4\u3002\u8be5\u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684\u6570\u7ec4\uff0c\u5176\u5143\u7d20\u4e0e List \u4e2d\u7684\u5143\u7d20\u5bf9\u5e94\u3002<\/p>\n<p><span>\u7acb\u5373\u5b66\u4e60<\/span>\u201c\u201d\uff1b<\/p>\n<pre>List&lt;String&gt; names = new ArrayList&lt;&gt;();\n\/\/ \u6dfb\u52a0\u5143\u7d20\u5230\u5217\u8868\nnames.add(\"John\");\nnames.add(\"Jane\");\nnames.add(\"Alice\");\n\n\/\/ \u5c06 List \u8f6c\u6362\u4e3a String \u6570\u7ec4\nString[] namesArray = names.toArray(new String[0]);<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p><strong>2. \u4f7f\u7528 for-each \u5faa\u73af<\/strong><\/p>\n<p>\u4e5f\u53ef\u4ee5\u4f7f\u7528 for-each \u5faa\u73af\u5c06 List \u8f6c\u6362\u4e3a\u6570\u7ec4\u3002\u901a\u8fc7\u8fed\u4ee3 List\uff0c\u53ef\u4ee5\u5c06\u6bcf\u4e2a\u5143\u7d20\u590d\u5236\u5230\u6570\u7ec4\u4e2d\u3002<\/p>\n<pre>List&lt;Integer&gt; numbers = new ArrayList&lt;&gt;();\n\/\/ \u6dfb\u52a0\u5143\u7d20\u5230\u5217\u8868\nnumbers.add(1);\nnumbers.add(2);\nnumbers.add(3);\n\n\/\/ \u521b\u5efa\u4e00\u4e2a\u7a7a\u6570\u7ec4\u6765\u5b58\u50a8 List \u5143\u7d20\nint[] numbersArray = new int[numbers.size()];\n\n\/\/ \u4f7f\u7528 for-each \u5faa\u73af\u5c06\u5143\u7d20\u590d\u5236\u5230\u6570\u7ec4\u4e2d\nint index = 0;\nfor (int number : numbers) {\n    numbersArray[index++] = number;\n}<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p>\u4ee5\u4e0a\u5c31\u662fjava\u600e\u4e48\u628alist\u8f6c\u6362\u6210\u6570\u7ec4\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>java \u4e2d\u5c06 list \u8f6c\u6362\u4e3a\u6570\u7ec4\u7684\u65b9\u6cd5\uff1a1. \u4f7f\u7528 toarray() \u65b9\u6cd5\u5c06 list \u8f6c\u6362\u4e3a\u6307\u5b9a\u7c7b\u578b\u7684\u6570\u7ec4\uff1b2. \u4f7f\u7528 for-each \u5faa\u73af\u8fed\u4ee3 list \u5e76\u5c06\u6bcf\u4e2a\u5143\u7d20\u590d\u5236\u5230\u6570\u7ec4\u4e2d\u3002 \u5982\u4f55\u5c06 Java List \u8f6c\u6362\u4e3a\u6570\u7ec4 \u5728 Java \u4e2d\uff0c\u5c06 List \u8f6c\u6362\u4e3a\u6570\u7ec4\u6709\u4e24\u79cd\u5e38\u89c1\u7684\u65b9\u6cd5\uff1a 1. \u4f7f\u7528 toArray() \u65b9\u6cd5 toArray() \u65b9\u6cd5\u53ef\u4ee5\u5c06 List \u8f6c\u6362\u4e3a\u6307\u5b9a\u7c7b\u578b T \u7684\u6570\u7ec4\u3002\u8be5\u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684\u6570\u7ec4\uff0c\u5176\u5143\u7d20\u4e0e List \u4e2d\u7684\u5143\u7d20\u5bf9\u5e94\u3002 \u7acb\u5373\u5b66\u4e60\u201c\u201d\uff1b List&lt;String&gt; names = new ArrayList&lt;&gt;(); \/\/ \u6dfb\u52a0\u5143\u7d20\u5230\u5217\u8868 names.add(&#8220;John&#8221;); names.add(&#8220;Jane&#8221;); names.add(&#8220;Alice&#8221;); \/\/ \u5c06 List \u8f6c\u6362\u4e3a String \u6570\u7ec4 String[] namesArray = [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-35312","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/35312","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=35312"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/35312\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=35312"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=35312"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=35312"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}