{"id":11926,"date":"2023-11-28T22:37:57","date_gmt":"2023-11-28T14:37:57","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=11926"},"modified":"2023-11-30T18:21:33","modified_gmt":"2023-11-30T10:21:33","slug":"javascript-zhongthis-shi-shen-me-zai-bu-tong-chang","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/11\/28\/javascript-zhongthis-shi-shen-me-zai-bu-tong-chang\/","title":{"rendered":"JavaScript \u4e2d this \u662f\u4ec0\u4e48\uff1f\u5728\u4e0d\u540c\u573a\u666f\u4e2d\u5206\u522b\u4ee3\u8868\u4ec0\u4e48\uff1f"},"content":{"rendered":"

\u5728 JavaScript \u4e2d\uff0cthis<\/code> \u5173\u952e\u5b57\u4ee3\u8868\u5f53\u524d\u6267\u884c\u4ee3\u7801\u7684\u4e0a\u4e0b\u6587\uff0c\u5b83\u7684\u503c\u5728\u4e0d\u540c\u60c5\u51b5\u4e0b\u4f1a\u6709\u4e0d\u540c\u7684\u6307\u5411\uff0c\u53d6\u51b3\u4e8e\u51fd\u6570\u662f\u5982\u4f55\u88ab\u8c03\u7528\u7684\u3002<\/p>\n

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    \n
  1. \n

    \u5168\u5c40\u4e0a\u4e0b\u6587\uff1a<\/strong>
    \n\u5728\u5168\u5c40\u4f5c\u7528\u57df\u4e2d\uff0cthis<\/code> \u6307\u5411\u5168\u5c40\u5bf9\u8c61\uff0c\u5728\u6d4f\u89c8\u5668\u73af\u5883\u4e2d\u6307\u5411 window<\/code> \u5bf9\u8c61\uff0c\u5728 Node.js \u4e2d\u6307\u5411 global<\/code> \u5bf9\u8c61\u3002<\/p>\n<\/li>\n

  2. \n

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      \n
    • \u5728\u666e\u901a\u51fd\u6570\u5185\u90e8\uff0cthis<\/code> \u7684\u503c\u53d6\u51b3\u4e8e\u51fd\u6570\u7684\u8c03\u7528\u65b9\u5f0f\u3002\n
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      • \n

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        \n\u5728\u4e8b\u4ef6\u5904\u7406\u51fd\u6570\u4e2d\uff0cthis<\/code> \u6307\u5411\u89e6\u53d1\u4e8b\u4ef6\u7684 DOM \u5143\u7d20\u3002<\/p>\n<\/li>\n

      • \n

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        \n\u5f53\u4e00\u4e2a\u51fd\u6570\u88ab\u7528\u4f5c\u6784\u9020\u51fd\u6570\uff08\u4f7f\u7528 new<\/code> \u5173\u952e\u5b57\uff09\uff0cthis<\/code> \u6307\u5411\u65b0\u521b\u5efa\u7684\u5b9e\u4f8b\u5bf9\u8c61\u3002<\/p>\n<\/li>\n

      • \n

        apply()<\/code>\u3001call()<\/code>\u3001bind()<\/code>\uff1a<\/strong>
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        \u603b\u7ed3\u6765\u8bf4\uff0cthis<\/code> \u7684\u6307\u5411\u662f\u52a8\u6001\u53d8\u5316\u7684\uff0c\u53d6\u51b3\u4e8e\u51fd\u6570\u88ab\u8c03\u7528\u7684\u65b9\u5f0f\u3002\u5728\u4e0d\u540c\u7684\u573a\u666f\u4e0b\uff0cthis<\/code> \u53ef\u80fd\u6307\u5411\u4e0d\u540c\u7684\u5bf9\u8c61\u6216\u503c\uff0c\u9700\u8981\u6839\u636e\u5b9e\u9645\u60c5\u51b5\u8fdb\u884c\u6ce8\u610f\u548c\u5904\u7406\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"

        \u5728 JavaScript \u4e2d\uff0cthis \u5173\u952e\u5b57\u4ee3\u8868\u5f53\u524d\u6267\u884c\u4ee3\u7801\u7684\u4e0a\u4e0b\u6587\uff0c\u5b83\u7684\u503c\u5728\u4e0d\u540c\u60c5\u51b5\u4e0b\u4f1a\u6709\u4e0d\u540c\u7684\u6307\u5411\uff0c\u53d6\u51b3 […]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[115],"tags":[],"class_list":["post-11926","post","type-post","status-publish","format-standard","hentry","category-javascript"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/11926","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=11926"}],"version-history":[{"count":2,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/11926\/revisions"}],"predecessor-version":[{"id":13625,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/11926\/revisions\/13625"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=11926"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=11926"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=11926"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}