JavaScript是一种解释型语言,所以能无法达到和C/Java之类的水平,限制了它能在客户端所做的事情,为了能改进他的性能,我想基于我以前给JavaScript做过的很多测试来谈谈自己的经验,希望能帮助大家改进自己的JavaScript脚本性能。 语言层次方面 循环 循环是很常用的一个控制结构,大部分东西要依靠它来完成,在JavaScript中,我...
call(), andapply(). If it sounds odd to you that a function might have its own methods - then remember that every function in JavaScript is an object. Readthisarticle for a refresher. You might also wonder what the difference is between a function and a method. I believe the descriptors...
代码语言:javascript 复制 // min/max number in an arrayvarnumbers=[5,6,2,3,7];// using Math.min/Math.max applyvarmax=Math.max.apply(null,numbers);// This about equal to Math.max(numbers[0], ...)// or Math.max(5, 6, ...)varmin=Math.min.apply(null,numbers);// vs. simple...
// calling greet() function by passing two argumentsletresult = greet.apply(personName, ["Good morning","How are you?"]); console.log(result); Run Code Output Taylor, Good morning. How are you? In the above program, we have used theapply()method to invoke thegreet()function. Inside ...
1. call与apply的概述call()和apply()是JavaScript内置的函数调用方式，它们允许你指定函数中的this值。call()接受一个参数列表，而apply()则接受一个参数数组。1.1 call方法Function.prototype.call()允许你使用指定的this值和参数执行函数，如果函数无返回值，则返回undefined。1.2 apply方法apply()...
JavaScript Function.apply() 函数详解,apply()函数用于调用当前函数functionObject,并可同时使用指定对象thisObj作为本次函数执行时函数内部的this指针引用。该函数属于Function对象,所有主流浏览器均支持该函数。语法functionObject.apply([thisObj[,argsArray]...
javaScript--Function.apply的用法 1.每个函数都包括两个非继承来的方法,apply和call。 2.相同点:两个方法作用都相同。 都是在特定的作用域中调用函数,等于设置函数体内this对象的值,以扩充函数赖以运行的作用域。(即继承) 一般来说,this总是指向调用某个方法的对象,但是使用call()和apply()方法时,就会改变this...
apply([thisObj,argArray]) 调用函数,并用指定对象替换函数的 this 值,同时用指定数组替换函数的参数。 function callMe(arg1, arg2){ var s = ""; s += "this value: " + this; s += " "; for (i in callMe.arguments) { s += "arguments: " + callMe.argumentsi; s += " "; } ret...
Math.max.apply(0, [1,2,3]);// Will also return 3 Try it Yourself » JavaScript Strict Mode In JavaScript strict mode, if the first argument of theapply()method is not an object, it becomes the owner (object) of the invoked function. In "non-strict" mode, it becomes the global...
JavaScript: The Definitive Guide, 6th Edition by David Flanagan Buy on Amazon Name Function.apply() — invoke a function as a method of an object Synopsis function.apply(thisobj, args) Arguments thisobj The object to which function is to be applied. In the body of the function, thisobj...