{"id":433,"date":"2024-02-16T08:32:00","date_gmt":"2024-02-16T00:32:00","guid":{"rendered":"https:\/\/mitongxue.cn\/?p=433"},"modified":"2026-06-16T14:47:05","modified_gmt":"2026-06-16T06:47:05","slug":"%e6%80%8e%e6%a0%b7%e5%bf%ab%e9%80%9f%e6%b8%85%e7%a9%ba%e5%a4%a7%e6%95%b0%e7%bb%84","status":"publish","type":"post","link":"https:\/\/mitongxue.cn\/index.php\/2024\/02\/16\/%e6%80%8e%e6%a0%b7%e5%bf%ab%e9%80%9f%e6%b8%85%e7%a9%ba%e5%a4%a7%e6%95%b0%e7%bb%84\/","title":{"rendered":"\u600e\u6837\u5feb\u901f\u6e05\u7a7a\u5927\u6570\u7ec4"},"content":{"rendered":"\n<h1 class=\"wp-block-heading\">\u4e00\u3001<code>arr.length = 0<\/code> \u6e05\u7a7a\u6570\u7ec4\u539f\u7406<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">1. JS \u6570\u7ec4\u672c\u8d28\uff1a\u7279\u6b8a\u5bf9\u8c61\uff0c<code>length<\/code> \u662f\u53ef\u8bfb\u5199\u5c5e\u6027<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">JavaScript \u6570\u7ec4\u4e0d\u662f\u8fde\u7eed\u5185\u5b58\u5757\uff0c\u662f<strong>\u952e\u4e3a\u6570\u5b57\u3001\u81ea\u5e26 length \u5c5e\u6027<\/strong>\u7684 Object\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>const arr = &#91;1,2,3];\n\/\/ \u5185\u90e8\u7ed3\u6784\u8fd1\u4f3c\n{\n  0: 1,\n  1: 2,\n  2: 3,\n  length: 3\n}\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u89c4\u8303\u89c4\u5b9a\uff1a<strong>\u76f4\u63a5\u7ed9 length \u8d4b\u503c\u5c0f\u4e8e\u5f53\u524d\u957f\u5ea6\uff0c\u4f1a\u81ea\u52a8\u5220\u9664\u7d22\u5f15\u8d85\u51fa length \u7684\u6240\u6709\u5143\u7d20<\/strong>\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6267\u884c <code>arr.length = 0<\/code>\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>length \u53d8\u4e3a 0<\/li>\n\n\n\n<li>\u5220\u9664\u7d22\u5f15 <code>0\u30011\u30012...<\/code> \u5168\u90e8\u952e<\/li>\n\n\n\n<li>\u6570\u7ec4\u53d8\u4e3a\u7a7a <code>[]<\/code><\/li>\n\n\n\n<li>\u539f\u6570\u7ec4\u5f15\u7528\u4e0d\u53d8\uff08\u539f\u5730\u4fee\u6539\uff0c\u4e0d\u65b0\u5efa\u6570\u7ec4\uff09<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">2. \u548c\u5176\u4ed6\u6e05\u7a7a\u65b9\u5f0f\u5bf9\u6bd4<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">\u65b9\u5f0f 1\uff1a<code>arr.length = 0<\/code>\uff08\u539f\u5730\u6e05\u7a7a\uff0c\u63a8\u8350\uff09<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>let arr = &#91;1,2,3,4,5];\narr.length = 0;\nconsole.log(arr); 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