{"id":168976,"date":"2024-05-08T16:35:44","date_gmt":"2024-05-08T08:35:44","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/168976.html"},"modified":"2024-05-08T16:35:47","modified_gmt":"2024-05-08T08:35:47","slug":"javascript-%e4%b8%ba%e4%bb%80%e4%b9%88%e8%a6%81%e6%8a%8a-this-%e6%9a%b4%e9%9c%b2%e5%87%ba%e6%9d%a5","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/168976.html","title":{"rendered":"JavaScript \u4e3a\u4ec0\u4e48\u8981\u628a this \u66b4\u9732\u51fa\u6765"},"content":{"rendered":"

\"JavaScript<\/p>\n

JavaScript \u4e4b\u6240\u4ee5\u8981\u5c06 this<\/code> \u66b4\u9732\u51fa\u6765\uff0c\u662f\u56e0\u4e3a\u5b83\u4e3a\u5f00\u53d1\u4eba\u5458\u63d0\u4f9b\u4e86\u6267\u884c\u4e0a\u4e0b\u6587\u7684\u5f15\u7528\u3001\u589e\u52a0\u4e86\u4ee3\u7801\u7684\u7075\u6d3b\u6027<\/strong>\u3001\u5141\u8bb8\u66f4\u52a0\u7cbe\u7ec6\u5730\u63a7\u5236\u51fd\u6570\u7684\u6267\u884c\u3002\u901a\u8fc7 this<\/code> \u5173\u952e\u5b57\uff0c\u51fd\u6570\u53ef\u4ee5\u8bbf\u95ee\u5b83\u4eec\u6240\u5c5e\u7684\u6216\u8005\u88ab\u8c03\u7528\u65f6\u7684\u5bf9\u8c61\uff0c\u5b9e\u73b0\u4e86\u51fd\u6570\u4e0e\u5bf9\u8c61\u7684\u7ed1\u5b9a\uff0c\u8fd9\u5728\u9762\u5411\u5bf9\u8c61\u7f16\u7a0b\u4e2d\u5c24\u4e3a\u91cd\u8981\u3002\u4f8b\u5982\uff0c\u5728\u521b\u5efa\u6784\u9020\u51fd\u6570\u65f6\uff0cthis<\/code> \u53ef\u4ee5\u5f15\u7528\u65b0\u521b\u5efa\u7684\u5bf9\u8c61\u5b9e\u4f8b\uff0c\u8fd9\u6837\u5f00\u53d1\u8005\u5c31\u53ef\u4ee5\u4e3a\u65b0\u5bf9\u8c61\u5b9a\u4e49\u5c5e\u6027\u548c\u65b9\u6cd5\u3002\u8fd9\u79cd\u52a8\u6001\u4e0a\u4e0b\u6587\u7684\u529f\u80fd\u5728\u7f16\u5199\u9ad8\u590d\u7528\u7684\u4ee3\u7801\u5e93\u548c\u7c7b\u7ed3\u6784\u65f6\u6781\u4e3a\u6709\u5229\u3002 <\/p>\n<\/p>\n

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\u4e00\u3001THIS<\/code> \u5728\u4e0d\u540c\u573a\u666f\u4e0b\u7684\u884c\u4e3a<\/h3>\n<\/p>\n

this<\/code> \u5728JavaScript\u4e2d\u7684\u884c\u4e3a\u4f1a\u6839\u636e\u5176\u4f7f\u7528\u7684\u4e0a\u4e0b\u6587\u800c\u6539\u53d8\u3002\u8fd9\u80fd\u591f\u4f7f\u7a0b\u5e8f\u5458\u638c\u63a7\u51fd\u6570\u7684\u884c\u4e3a\uff0c\u5e76\u4ee5\u66f4\u52a8\u6001\u7684\u65b9\u5f0f\u4e0e\u5bf9\u8c61\u7684\u5c5e\u6027\u548c\u65b9\u6cd5\u4ea4\u4e92\u3002<\/p>\n<\/p>\n

1. \u5168\u5c40\u4e0a\u4e0b\u6587\u4e2d\u7684 this<\/code><\/h4>\n<\/p>\n

\u5728\u5168\u5c40\u6267\u884c\u4e0a\u4e0b\u6587\u4e2d\uff08\u5728\u4efb\u4f55\u51fd\u6570\u5916\u90e8\uff09\uff0cthis<\/code> \u5f15\u7528\u5168\u5c40\u5bf9\u8c61\u3002\u5728\u6d4f\u89c8\u5668\u4e2d\uff0c\u5168\u5c40\u5bf9\u8c61\u5373 window<\/code>\uff0c\u800c\u5728Node.js\u4e2d\u901a\u5e38\u662f global<\/code>\u3002\u8fd9\u5141\u8bb8\u5728\u5168\u5c40\u8303\u56f4\u5185\u521b\u5efa\u6216\u8bbf\u95ee\u5168\u5c40\u53d8\u91cf\u3002<\/p>\n<\/p>\n

2. \u51fd\u6570\u4e0a\u4e0b\u6587\u4e2d\u7684 this<\/code><\/h4>\n<\/p>\n

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\u4e8c\u3001THIS<\/code> \u589e\u52a0\u7684\u4ee3\u7801\u7075\u6d3b\u6027<\/h3>\n<\/p>\n

this<\/code> \u5173\u952e\u5b57\u63d0\u4f9b\u4e86\u4e00\u79cd\u673a\u5236\uff0c\u5141\u8bb8\u51fd\u6570\u6216\u65b9\u6cd5\u5728\u4e0d\u540c\u7684\u5bf9\u8c61\u95f4\u5171\u4eab\uff0c\u4ece\u800c\u5b9e\u73b0\u4ee3\u7801\u7684\u590d\u7528\u3002<\/p>\n<\/p>\n

1. \u5bf9\u8c61\u65b9\u6cd5\u4e2d\u7684 this<\/code><\/h4>\n<\/p>\n

\u5f53\u51fd\u6570\u4f5c\u4e3a\u5bf9\u8c61\u7684\u65b9\u6cd5\u88ab\u8c03\u7528\u65f6\uff0cthis<\/code> \u4f1a\u6307\u5411\u8be5\u5bf9\u8c61\u3002\u8fd9\u6837\u7684\u529f\u80fd\u5bf9\u4e8e\u9762\u5411\u5bf9\u8c61\u7a0b\u5e8f\u8bbe\u8ba1\u6765\u8bf4\u975e\u5e38\u5173\u952e\uff0c\u56e0\u4e3a\u5b83\u8ba9\u65b9\u6cd5\u53ef\u4ee5\u8bbf\u95ee\u548c\u64cd\u4f5c\u8c03\u7528\u5b83\u7684\u5bf9\u8c61\u7684\u6570\u636e\u3002<\/p>\n<\/p>\n

2. \u6784\u9020\u5668\u4e2d\u7684 this<\/code><\/h4>\n<\/p>\n

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\u4e09\u3001THIS<\/code> \u4e0e\u51fd\u6570\u6267\u884c\u63a7\u5236<\/h3>\n<\/p>\n

this<\/code> \u5141\u8bb8\u5728\u51fd\u6570\u6267\u884c\u65f6\uff0c\u5bf9\u51fd\u6570\u7684\u4e0a\u4e0b\u6587\u8fdb\u884c\u7ec6\u7c92\u5ea6\u7684\u63a7\u5236\u3002\u8fd9\u4e00\u70b9\u5728\u56de\u8c03\u51fd\u6570\u548c\u95ed\u5305\u4e2d\u5c24\u4e3a\u7a81\u51fa\u3002<\/p>\n<\/p>\n

1. \u56de\u8c03\u51fd\u6570\u4e2d\u7684 this<\/code><\/h4>\n<\/p>\n

\u5728\u4e8b\u4ef6\u5904\u7406\u5668\u6216\u56de\u8c03\u51fd\u6570\u4e2d\uff0cthis<\/code> \u7684\u503c\u901a\u5e38\u662f\u8c03\u7528\u5b83\u7684\u5bf9\u8c61\uff0c\u8fd9\u4f1a\u5728\u6d89\u53caDOM\u4e8b\u4ef6\u5904\u7406\u65f6\u975e\u5e38\u6709\u7528\uff0c\u56e0\u4e3a this<\/code> \u53ef\u4ee5\u63d0\u4f9b\u5bf9\u89e6\u53d1\u4e8b\u4ef6\u5143\u7d20\u7684\u76f4\u63a5\u5f15\u7528\u3002<\/p>\n<\/p>\n

2. \u95ed\u5305\u4e2d\u7684 this<\/code><\/h4>\n<\/p>\n

\u95ed\u5305\u53ef\u80fd\u4f1a\u6355\u83b7\u5176\u521b\u5efa\u65f6\u6240\u5728\u7684\u4e0a\u4e0b\u6587\u4e2d\u7684 this<\/code>\uff0c\u8fd9\u79cd\u884c\u4e3a\u53ef\u4ee5\u7528\u6765\u7ef4\u6301\u5bf9\u7279\u5b9a\u5bf9\u8c61\u7684\u5f15\u7528\uff0c\u5373\u4fbf\u5728\u539f\u59cb\u4e0a\u4e0b\u6587\u5df2\u7ecf\u4e0d\u53ef\u7528\u7684\u60c5\u51b5\u4e0b\u3002<\/p>\n<\/p>\n

\u56db\u3001THIS<\/code> \u5728\u73b0\u4ee3JavaScript\u6846\u67b6\u4e2d\u7684\u5e94\u7528<\/h3>\n<\/p>\n

\u73b0\u4ee3JavaScript\u6846\u67b6\u548c\u5e93\uff08\u5982React\u3001Vue\u3001Angular\u7b49\uff09\u4e5f\u5927\u91cf\u5229\u7528 this<\/code> \u4ee5\u7ef4\u6301\u5185\u90e8\u72b6\u6001\uff0c\u6216\u8005\u7ba1\u7406\u7ec4\u4ef6\u4e4b\u95f4\u7684\u901a\u4fe1\u3002<\/p>\n<\/p>\n

1. \u72b6\u6001\u7ba1\u7406<\/h4>\n<\/p>\n

\u5728\u8bb8\u591aJavaScript\u5e93\u6216\u6846\u67b6\u4e2d\uff0cthis<\/code> \u7528\u4e8e\u8bbf\u95ee\u548c\u7ba1\u7406\u7ec4\u4ef6\u7684\u72b6\u6001\u5bf9\u8c61\u3002\u8fd9\u8ba9\u72b6\u6001\u7684\u7ba1\u7406\u53d8\u5f97\u96c6\u4e2d\u4e14\u6613\u4e8e\u8ffd\u8e2a\u3002<\/p>\n<\/p>\n

2. \u7ec4\u4ef6\u901a\u4fe1<\/h4>\n<\/p>\n

\u901a\u8fc7 this<\/code>\uff0c\u7ec4\u4ef6\u53ef\u4ee5\u8bbf\u95ee\u7ed1\u5b9a\u5728\u5176\u5b9e\u4f8b\u4e0a\u7684\u53c2\u6570\u6216\u51fd\u6570\uff0c\u5b9e\u73b0\u4e86\u7075\u6d3b\u7684\u7ec4\u4ef6\u95f4\u901a\u4fe1\u673a\u5236\u3002<\/p>\n<\/p>\n

JavaScript\u7684 this<\/code> \u5173\u952e\u5b57\u662f\u5176\u5f3a\u5927\u529f\u80fd\u548c\u7075\u6d3b\u6027\u7684\u6838\u5fc3\u3002\u5b83\u4e0d\u4ec5\u662f\u9762\u5411\u5bf9\u8c61\u7f16\u7a0b\u7684\u4e00\u4e2a\u91cd\u8981\u6982\u5ff5\uff0c\u800c\u4e14\u8fd8\u662f\u9ad8\u7ea7\u51fd\u6570\u7f16\u7a0b\u98ce\u683c\u7684\u57fa\u77f3\u3002\u5c3d\u7ba1 this<\/code> \u7684\u5de5\u4f5c\u65b9\u5f0f\u53ef\u80fd\u4f1a\u8ba9\u4eba\u56f0\u60d1\uff0c\u4f46\u4e00\u65e6\u7406\u89e3\u5176\u884c\u4e3a\uff0c\u5b83\u4fbf\u6210\u4e3a\u7f16\u5199\u5f3a\u5927\u3001\u7075\u6d3b\u4e14\u6613\u4e8e\u7ef4\u62a4\u7684\u4ee3\u7801\u4e0d\u53ef\u6216\u7f3a\u7684\u5de5\u5177\u3002<\/p>\n<\/p>\n

\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n

\u4e3a\u4ec0\u4e48 JavaScript \u4e2d\u9700\u8981\u4f7f\u7528 this \u5173\u952e\u5b57\uff1f<\/strong>
\nJavaScript \u4f7f\u7528 this \u5173\u952e\u5b57\u6765\u5f15\u7528\u5f53\u524d\u6267\u884c\u4ee3\u7801\u7684\u4e0a\u4e0b\u6587\u5bf9\u8c61\u3002\u901a\u8fc7\u4f7f\u7528 this \u5173\u952e\u5b57\uff0c\u6211\u4eec\u53ef\u4ee5\u8bbf\u95ee\u5f53\u524d\u5bf9\u8c61\u7684\u5c5e\u6027\u548c\u65b9\u6cd5\uff0c\u4ee5\u53ca\u5728\u6784\u9020\u51fd\u6570\u4e2d\u521b\u5efa\u65b0\u5bf9\u8c61\u3002<\/p>\n

JavaScript \u4e2d this \u7684\u4f5c\u7528\u662f\u4ec0\u4e48\uff1f<\/strong>
\nthis \u5728 JavaScript \u4e2d\u5177\u6709\u591a\u79cd\u4f5c\u7528\u3002\u5b83\u53ef\u4ee5\u7528\u4e8e\u5f15\u7528\u5f53\u524d\u5bf9\u8c61\u7684\u5c5e\u6027\u548c\u65b9\u6cd5\uff0c\u4e5f\u53ef\u4ee5\u7528\u4e8e\u5728\u6784\u9020\u51fd\u6570\u4e2d\u521b\u5efa\u65b0\u7684\u5bf9\u8c61\u3002\u6b64\u5916\uff0cthis \u8fd8\u53ef\u4ee5\u7528\u4e8e\u5728\u4e8b\u4ef6\u5904\u7406\u7a0b\u5e8f\u4e2d\u5f15\u7528\u89e6\u53d1\u4e8b\u4ef6\u7684\u5143\u7d20\u3002<\/p>\n

\u4e3a\u4ec0\u4e48\u8981\u5c06 this \u66b4\u9732\u7ed9\u5f00\u53d1\u8005\uff1f<\/strong>
\n\u5c06 this \u5173\u952e\u5b57\u66b4\u9732\u7ed9\u5f00\u53d1\u8005\u53ef\u4ee5\u8ba9\u4ed6\u4eec\u66f4\u7075\u6d3b\u5730\u64cd\u4f5c\u5bf9\u8c61\u548c\u5904\u7406\u4e8b\u4ef6\u3002\u5f00\u53d1\u8005\u53ef\u4ee5\u4f7f\u7528 this \u5173\u952e\u5b57\u6765\u5f15\u7528\u5f53\u524d\u5bf9\u8c61\u7684\u5c5e\u6027\u548c\u65b9\u6cd5\uff0c\u4ece\u800c\u5b9e\u73b0\u5bf9\u5bf9\u8c61\u7684\u64cd\u4f5c\u3002\u6b64\u5916\uff0c\u66b4\u9732 this \u4e5f\u4f7f\u5f97\u5f00\u53d1\u8005\u53ef\u4ee5\u5728\u51fd\u6570\u5185\u90e8\u52a8\u6001\u5730\u521b\u5efa\u65b0\u7684\u5bf9\u8c61\uff0c\u4e3a\u6784\u9020\u51fd\u6570\u63d0\u4f9b\u66f4\u5927\u7684\u81ea\u7531\u5ea6\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"JavaScript \u4e4b\u6240\u4ee5\u8981\u5c06 this \u66b4\u9732\u51fa\u6765\uff0c\u662f\u56e0\u4e3a\u5b83\u4e3a\u5f00\u53d1\u4eba\u5458\u63d0\u4f9b\u4e86\u6267\u884c\u4e0a\u4e0b\u6587\u7684\u5f15\u7528\u3001\u589e\u52a0\u4e86\u4ee3\u7801\u7684\u7075 […]","protected":false},"author":3,"featured_media":168979,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/168976"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=168976"}],"version-history":[{"count":0,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/168976\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/168979"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=168976"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=168976"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=168976"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}