12functionPersonA(){3this.name = 'a';4this.say =function(){5console.log('A:' +this.name)6}7}89functionPersonB(){10this.name = 'b';11// console.log('B:' +this.name);12}1314vara =newPersonA();15varb =newPersonB();1617a.say.call(b);18 其中b对象想要调用a中的say方法,则...
该this关键字是在JavaScript中一个非常重要的概念,也是一个特别令人迷惑的这两个新的开发者和那些谁拥有在其他编程语言的经验。在JavaScript中,this是对对象的引用。该对象this是指可以改变,含蓄地基于它是否是全球性的,在对象上,或者在一个构造函数,也可以明确地变化根据的使用Function原型方法bind,call和apply。 尽管...
call 、bind 、 apply 这三个函数的第一个参数都是 this 的指向对象,第二个参数差别就来了: call 的参数是直接放进去的,第二第三第 n 个参数全都用逗号分隔,直接放到后面obj.myFun.call(db,'成都', ... ,'string' )。 apply 的所有参数都必须放在一个数组里面传进去obj.myFun.apply(db,['成都', ....
在下面的例子中,当调用 greet 方法的时候,该方法的this值会绑定到 obj 对象。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 functiongreet(){varreply=[this.animal,'typically sleep between',this.sleepDuration].join(' ');console.log(reply);}varobj={animal:'cats',sleepDuration:'12 and 16 ho...
In an event,thisrefers to theelementthat received the event. Methods likecall(),apply(), andbind()can referthistoany object. Note thisis not a variable. It is a keyword. You cannot change the value ofthis. See Also: The JavaScriptthisTutorial ...
A callback function in JavaScript is a function that is passed as an argument to another function and is invoked after some kind of event.
This has slightly less overhead than making asynchronous calls and can result in fewer render cycles because there's no intermediate state while awaiting results.To make a synchronous call from .NET to JavaScript in a client-side component, cast IJSRuntime to IJSInProcessRuntime to make the ...
fn.call:立即调用,返回函数执行结果,this指向第一个参数,后面可有多个参数,并且这些都是fn函数的参数。】 fn.call(this参数,形参1,形参2...) fn.apply:立即调用,返回函数的执行结果,this指向第一个参数,第二个参数是个数组,这个数组里内容是fn函数的参数。
In fact, JavaScript functions come with several methods built into Function.prototype. First let's take a look at call.function add (a, b) { return a + b; } // Outputs: 3 console.log(add(1, 2)); // Outputs: 3 console.log(add.call(this, 1, 2)); ...
Kernel里执行的很正常 如果在RTP里调用它们 代码语言:javascript 代码运行次数:0 运行 AI代码解释 intmain(){int p0=1;char*p1="22";int p2=333;test0();test1(p0);test2(p0,p2);test3(p0,p1,p2);return0;} build时就会报错了,更别提执行了 ...