{"id":109937,"date":"2020-05-31T17:43:10","date_gmt":"2020-05-31T09:43:10","guid":{"rendered":"http:\/\/4563.org\/?p=109937"},"modified":"2020-05-31T17:43:10","modified_gmt":"2020-05-31T09:43:10","slug":"%e4%bd%bf%e7%94%a8-call%e6%96%b9%e6%b3%95%e8%b0%83%e7%94%a8%e5%87%bd%e6%95%b0-%e5%92%8c-%e5%b0%86%e4%bd%9c%e7%94%a8%e5%9f%9f-this-%e7%9b%b4%e6%8e%a5%e4%bd%9c%e5%8f%82%e6%95%b0%e4%bc%a0%e5%85%a5","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=109937","title":{"rendered":"\u4f7f\u7528 call()\u65b9\u6cd5\u8c03\u7528\u51fd\u6570 \u548c \u5c06\u4f5c\u7528\u57df this \u76f4\u63a5\u4f5c\u53c2\u6570\u4f20\u5165\u6709\u4ec0\u4e48\u533a\u522b?"},"content":{"rendered":"
\n
\n
\n

\u4f7f\u7528 call()\u65b9\u6cd5\u8c03\u7528\u51fd\u6570 \u548c \u5c06\u4f5c\u7528\u57df this \u76f4\u63a5\u4f5c\u53c2\u6570\u4f20\u5165\u6709\u4ec0\u4e48\u533a\u522b? <\/h1>\n

<\/p>\n

\n
\u8cc7\u6df1\u5927\u4f6c : gromit1337 <\/span> <\/i> 0<\/span> <\/div>\n
<\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n
\u5c0f\u7a0b\u5e8f\u91cc\u7684\u4e00\u4e2a\u5c01\u88c5\u65b9\u6cd5\u9700\u8981\u8c03\u7528\u9875\u9762\u7684\u7ec4\u4ef6, \u8981\u7528\u5230 this.selectComponent().doThing() ,\u8fd9\u91cc\u5f15\u8d77\u4e86\u6807\u9898\u7684\u4e89\u8bae\u4e86 <\/div>\n
\u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (17<\/span>) <\/div>\n
<\/div>\n<\/p><\/div>\n<\/p><\/div>\n
    \n
  • \n
    \n
    \n
    \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : gromit1337 <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u611f\u89c9\u7528 call \u5c11\u4e86\u4e2a\u53c2\u6570,\u5c11\u4e86\u4e9b\u601d\u60f3\u8d1f\u62c5 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : liuy1994g <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    this \u548c\u53c2\u6570\u8fd8\u662f\u6709\u4e9b\u533a\u522b\u7684\u5427 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : rabbbit <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u9762\u5411\u5bf9\u8c61\u7f16\u7a0b\u548c\u51fd\u6570\u5f0f\u7f16\u7a0b? <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : ChanKc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u6ca1\u6709\u592a\u770b\u61c2
    this.selectComponent()\u548c selectComponent.call(this)\u7684\u5dee\u522b\uff1f
    \u5728\u4f60\u7684\u60c5\u51b5\u4e0b\u4f3c\u4e4e\u6ca1\u533a\u522b
    call \u4e00\u822c\u90fd\u53d1\u751f\u5728\uff0c\u5982\u679c\u4f60\u8981\u8c03\u7684\u8fd9\u4e2a\u65b9\u6cd5\uff0c\u4f60\u62c5\u5fc3\u6ca1\u6709
    \u6bd4\u5982\u4f60\u7684 this.selectComponent == null
    \u6b64\u65f6\u4f60\u53ea\u80fd\u53bb\u627e\u522b\u7684\u7c7b\u4f3c\u7684\u5bf9\u8c61\u7684\u65b9\u6cd5\u62ff\u8fc7\u6765\u7528\u4e00\u4e0b
    that.selectComponent.call(this)<\/p>\n

    \u793a\u4f8b\uff1a
    let obj = Object.create(null);
    obj.a = 1;
    Object.prototype.hasOwnProperty.call(obj,”a”); \/\/ true <\/div>\n<\/p><\/div>\n<\/li>\n

  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : ChanKc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u60f3\u4e86\u60f3\u4f60\u53ef\u80fd\u8981\u7684\u662f\u8fd9\u4e2a
    \u4f60\u7684 selectComponent \u53ea\u662f\u4e34\u65f6\u7528\u4e00\u4e0b\uff0c\u6bd4\u5982
    let obj = {};
    obj.selectComponent = function () { console.log(“s”) };
    obj.selectComponent();
    delete obj.selectComponent;<\/p>\n

    \u5982\u679c\u662f\u8fd9\u6837\uff0c\u7528 call
    (function selectComponent () {}).call(obj);<\/p>\n

    \u524d\u8005\u53ef\u80fd\u4f1a\u8986\u76d6\u5df2\u6709\u7684\u540c\u540d\u65b9\u6cd5\uff0c\u800c\u4e14\u53ef\u80fd\u5fd8\u8bb0 delete \u4ece\u800c\u5f71\u54cd Object.keys \u7b49\u65b9\u6cd5\u7684\u7ed3\u679c\u3002call \u6ca1\u6709\u90a3\u4e48\u5730\u201c\u4fb5\u5165\u6027\u201d <\/p><\/div>\n<\/p><\/div>\n<\/li>\n

  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : ChanKc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u8fd8\u662f\u8bf4\u4f60\u95ee\u7684\u662f
    func sum(self) {return self.a + self.b };
    func sum() { return this.a + this.b };
    \u7684\u533a\u522b\uff1f\u6211\u4e2a\u4eba\u559c\u6b22\u524d\u8005 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : longjiahui <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u5982\u679c\u4e0d\u662f\u67d0\u4e2a\u7c7b\u5bf9\u8c61\u6216\u5565\u6709\u610f\u4e49\u7684 this\uff0c\u611f\u89c9\u901a\u8fc7\u53c2\u6570\u4f20\u4f1a\u6bd4\u8f83\u597d\u3002
    \u4e0d\u7136 \u8981\u641e\u6e05\u695a\u8fd9\u4e2a this \u4f1a\u6162\u6162\u53d8\u5f97\u590d\u6742 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : gromit1337 <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    @ChanKc #6 \u5927\u6982\u662f\u4f60\u8fd9\u4e24\u4e2a\u7684\u533a\u522b\uff0c\u4e0b\u9762\u7684\u65b9\u6cd5\u7528 call \u8c03\u7528 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : Austaras <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u8fd9\u4e24\u4e2a\u90fd\u4e0d\u597d\uff0c \u7528 arrow function <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : pvgjfk <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u5728\u529f\u80fd\u6027\u4e0a\u6ca1\u5565\u533a\u522b,\u90fd\u80fd\u5b9e\u73b0\u4f60\u7684\u76ee\u7684. <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : pvgjfk <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u5fd8\u4e86\u8bf4\u4e86,\u5982\u679c\u4f60\u662f\u6211\u540c\u4e8b\u4f60\u8fd9\u6837\u5199\u4f1a\u88ab\u6211\u9a82\u7684 [\u72d7\u5934] <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : autoxbc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    this \u672c\u8d28\u4e0a\u5c31\u662f\u9690\u5f0f\u4f20\u53c2\u6570\uff0c\u9690\u5f0f\u7684\u76ee\u7684\u662f\u5199\u8d77\u6765\u7b80\u6d01\u4f18\u96c5\uff0c\u4e0d\u7b80\u6d01\u4e0d\u4f18\u96c5\u53cd\u800c\u70e7\u8111\u7684\u7528\u6cd5\u90fd\u662f\u9519\u7684\uff0c\u80cc\u79bb\u4e86\u8bbe\u8ba1\u521d\u8877 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : ChanKc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    @gromit1337 \u6ca1\u5565\u533a\u522b\uff0c\u4f46\u662f\u5982\u679c\u662f typescript\uff0c\u6d89\u53ca\u5230 private \u7684\u8bdd\uff0c#6 \u4e0a\u9762\u90a3\u4e2a\u662f\u4e0d\u884c\u7684 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : ChanKc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    @autoxbc this \u4e0d\u662f js \u91cc\u6700\u70e7\u8111\u7684\u4e1c\u897f\u4e4b\u4e00\u5417 <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : gromit1337 <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    @pvgjfk #11 \u4e3a\u4ec0\u4e48 \/doge <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : autoxbc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    @ChanKc #14
    this \u6ca1\u6709\u89e3\u51b3\u4efb\u4f55\u91cd\u8981\u7684\u95ee\u9898\uff0c\u53ea\u662f\u9690\u5f0f\u4f20\u53c2\u7684\u8bed\u6cd5\u7cd6\u3002\u5f53\u8bed\u6cd5\u7cd6\u5403\u8d77\u6765\u82e6\u65f6\uff0c\u5c31\u662f\u672c\u672b\u5012\u7f6e\u4e86\u3002\u90a3\u4e9b\u8bd5\u56fe\u7528 this \u70ab\u6280\u7684\u4eba\uff0c\u5176\u5b9e\u4e0d\u7406\u89e3\u8fd9\u4e2a\u4e1c\u897f <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : ChanKc <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    @autoxbc \u6ca1\u592a\u61c2\uff0c\u4ec0\u4e48\u662f\u62ff this \u70ab\u6280\uff1f\u5982\u679c\u4e0d\u61c2 this \u53c8\u600e\u4e48\u62ff this \u70ab\u6280\uff1f <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n","protected":false},"excerpt":{"rendered":"

    \u4f7f\u7528 call()\u65b9\u6cd5\u8c03\u7528\u51fd\u6570 \u548c…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/109937"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=109937"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/109937\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=109937"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=109937"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=109937"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}