{"id":10167,"date":"2023-11-28T21:27:44","date_gmt":"2023-11-28T13:27:44","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=10167"},"modified":"2023-11-30T19:04:44","modified_gmt":"2023-11-30T11:04:44","slug":"javascript-zhong-ru-he-gai-bianthis-zhi-zhen-de-zh","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/11\/28\/javascript-zhong-ru-he-gai-bianthis-zhi-zhen-de-zh\/","title":{"rendered":"JavaScript \u4e2d\u5982\u4f55\u6539\u53d8 this \u6307\u9488\u7684\u6307\u5411\uff1f"},"content":{"rendered":"<p>JavaScript \u4e2d\u6709\u51e0\u79cd\u65b9\u6cd5\u53ef\u4ee5\u6539\u53d8 <code>this<\/code> \u6307\u9488\u7684\u6307\u5411\uff1a<\/p>\n<h3><a id=\"1%E4%BD%BF%E7%94%A8-bind%E6%96%B9%E6%B3%95%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>1. \u4f7f\u7528 <code>bind()<\/code> \u65b9\u6cd5\uff1a<\/h3>\n<ul>\n<li><code>bind()<\/code> \u65b9\u6cd5\u521b\u5efa\u4e00\u4e2a\u65b0\u51fd\u6570\uff0c\u8c03\u7528\u65f6 <code>this<\/code> \u7684\u503c\u4f1a\u88ab\u6307\u5b9a\u4e3a\u4f20\u9012\u7ed9 <code>bind()<\/code> \u7684\u7b2c\u4e00\u4e2a\u53c2\u6570\u3002<\/li>\n<li>\u793a\u4f8b\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-javascript\">const obj = { name: 'Alice' };\n\nfunction sayName() {\n  console.log(this.name);\n}\n\nconst boundFunction = sayName.bind(obj);\nboundFunction(); \/\/ \u8f93\u51fa\uff1aAlice\n<\/code><\/pre>\n<h3><a id=\"2%E4%BD%BF%E7%94%A8-call%E6%88%96-apply%E6%96%B9%E6%B3%95%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>2. \u4f7f\u7528 <code>call()<\/code> \u6216 <code>apply()<\/code> \u65b9\u6cd5\uff1a<\/h3>\n<ul>\n<li><code>call()<\/code> \u548c <code>apply()<\/code> \u65b9\u6cd5\u53ef\u4ee5\u7acb\u5373\u8c03\u7528\u51fd\u6570\uff0c\u53ef\u4ee5\u4f20\u9012\u4e00\u4e2a\u6307\u5b9a\u7684 <code>this<\/code> \u503c\u548c\u53c2\u6570\u5217\u8868\u3002<\/li>\n<li><code>call()<\/code> \u65b9\u6cd5\u7684\u53c2\u6570\u662f\u9010\u4e2a\u4f20\u5165\u7684\uff0c\u800c <code>apply()<\/code> \u65b9\u6cd5\u63a5\u53d7\u4e00\u4e2a\u6570\u7ec4\u4f5c\u4e3a\u53c2\u6570\u3002<\/li>\n<li>\u793a\u4f8b\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-javascript\">const obj = { name: 'Bob' };\n\nfunction sayName() {\n  console.log(this.name);\n}\n\nsayName.call(obj); \/\/ \u8f93\u51fa\uff1aBob\nsayName.apply(obj); \/\/ \u8f93\u51fa\uff1aBob\n<\/code><\/pre>\n<h3><a id=\"3%E4%BD%BF%E7%94%A8%E7%AE%AD%E5%A4%B4%E5%87%BD%E6%95%B0%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>3. \u4f7f\u7528\u7bad\u5934\u51fd\u6570\uff1a<\/h3>\n<ul>\n<li>\u7bad\u5934\u51fd\u6570\u4e0d\u4f1a\u6539\u53d8 <code>this<\/code> \u7684\u6307\u5411\uff0c\u5b83\u4f1a\u6355\u83b7\u51fd\u6570\u58f0\u660e\u65f6\u6240\u5904\u7684\u4e0a\u4e0b\u6587\u7684 <code>this<\/code> \u503c\u3002<\/li>\n<li>\u793a\u4f8b\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-javascript\">const obj = { name: 'Charlie' };\n\nconst sayName = () =&gt; {\n  console.log(this.name);\n};\n\nsayName.call(obj); \/\/ \u8f93\u51fa\uff1aCharlie\n<\/code><\/pre>\n<h3><a id=\"4%E6%89%8B%E5%8A%A8%E8%B5%8B%E5%80%BC%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>4. \u624b\u52a8\u8d4b\u503c\uff1a<\/h3>\n<ul>\n<li>\u53ef\u4ee5\u624b\u52a8\u8d4b\u503c\u7ed9\u4e00\u4e2a\u53d8\u91cf\uff0c\u5728\u9700\u8981\u65f6\u4f7f\u7528\u8be5\u53d8\u91cf\u3002<\/li>\n<li>\u793a\u4f8b\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-javascript\">const obj = { name: 'David' };\n\nfunction sayName() {\n  const self = this;\n  function innerFunction() {\n    console.log(self.name);\n  }\n  innerFunction();\n}\n\nsayName.call(obj); \/\/ \u8f93\u51fa\uff1aDavid\n<\/code><\/pre>\n<p>\u8fd9\u4e9b\u65b9\u6cd5\u53ef\u4ee5\u6839\u636e\u9700\u8981\u6765\u6539\u53d8\u51fd\u6570\u6267\u884c\u65f6\u7684 <code>this<\/code> \u6307\u5411\uff0c\u9009\u62e9\u9002\u5f53\u7684\u65b9\u5f0f\u53d6\u51b3\u4e8e\u5177\u4f53\u7684\u60c5\u51b5\u548c\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>JavaScript \u4e2d\u6709\u51e0\u79cd\u65b9\u6cd5\u53ef\u4ee5\u6539\u53d8 this \u6307\u9488\u7684\u6307\u5411\uff1a 1. \u4f7f\u7528 bind() \u65b9\u6cd5\uff1a bind [&hellip;]<\/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-10167","post","type-post","status-publish","format-standard","hentry","category-javascript"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10167","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=10167"}],"version-history":[{"count":2,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10167\/revisions"}],"predecessor-version":[{"id":13669,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10167\/revisions\/13669"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=10167"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=10167"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=10167"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}