Function (Built-in Object)
Function (內置對象)
Function is the object from which JavaScript functions are derived. Functions are first-class data types in JavaScript, so they may be assigned to variables and passed to functions as you would any other piece of data. Functions are, of course, reference types.
The Function object provides both static properties like length and properties that convey useful information during the execution of the function, for example, the arguments[] array.
Constructor
var instanceName = new Function([arg1 [, arg2 [, ...]] ,] body);
The body parameter is a string containing the text that makes up the body of the function. The optional argN's are the names of the formal parameters the function accepts. For example:
var myAdd = new Function("x", "y", "return x + y");
var sum = myAdd(17, 34);
Properties
arguments[] An implicitly filled and implicitly available (directly usable as "arguments" from within the function) array of parameters that were passed to the function. This value is null if the function is not currently executing. (IE4+ (JScript 2.0+), MOZ, N3+ (JavaScript 1.1+), ECMA Edition 1)
arguments.callee Reference to the current function. This property is deprecated. (N4+, MOZ, IE5.5+)
arguments.caller Reference to the function that invoked the current function. This property is deprecated. (N3, IE4+)
arguments.length The number of arguments that were passed to the function. (IE4+ (JScript 2.0+), MOZ, N3+ (JavaScript 1.1+), ECMA Edition 1)
arity Numeric value indicating how many arguments the function expects. This property is deprecated. (N4+, MOZ)
caller Reference to the function that invoked the current function or null if called from the global context. (IE4+ (JScript 2.0+), MOZ, N3+)
constructor Reference to the constructor object that created the object. (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), ECMA Edition 1)
length The number of arguments the function expects to be passed. (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), ECMA Edition 1)
prototype Reference to the object's prototype. (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), ECMA Edition 1)
Methods
apply(thisArg [, argArray]) Invokes the function with the object referenced by thisArg as its context (so references to this in the function reference thisArg). The optional parameter argArray contains the list of parameters to pass to the function as it is invoked. (IE5.5+ (JScript 5.5+), N4.06+ (JavaScript 1.3+), MOZ, ECMA Edition 3)
call(thisArg [, arg1 [, arg2 [, ...]]]) Invokes the function with the object referenced by thisArg as its context (so references to this in the function reference thisArg). The optional parameters argN are passed to the function as it is invoked. (IE5.5+ (JScript 5.5+), N4.06+ (JavaScript 1.3+), MOZ, ECMA Edition 3)
toString() Returns the string version of the function source. The body of built-in and browser objects will typically be represented by the value "[native code]". (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), MOZ, ECMA Edition 1)
valueOf() Returns the string version of the function source. The body of built-in and browser objects will typically be represented by the value "[native code]". (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), MOZ, ECMA Edition 1)
Support
Supported in IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), MOZ, ECMAScript Edition 1.
Notes
General examples of functions are found throughout the book, but see Chapter 5 for examples of the advanced aspects of functions and the Function object.
Function (內置對象)
Function is the object from which JavaScript functions are derived. Functions are first-class data types in JavaScript, so they may be assigned to variables and passed to functions as you would any other piece of data. Functions are, of course, reference types.
The Function object provides both static properties like length and properties that convey useful information during the execution of the function, for example, the arguments[] array.
Constructor
var instanceName = new Function([arg1 [, arg2 [, ...]] ,] body);
The body parameter is a string containing the text that makes up the body of the function. The optional argN's are the names of the formal parameters the function accepts. For example:
var myAdd = new Function("x", "y", "return x + y");
var sum = myAdd(17, 34);
Properties
arguments[] An implicitly filled and implicitly available (directly usable as "arguments" from within the function) array of parameters that were passed to the function. This value is null if the function is not currently executing. (IE4+ (JScript 2.0+), MOZ, N3+ (JavaScript 1.1+), ECMA Edition 1)
arguments.callee Reference to the current function. This property is deprecated. (N4+, MOZ, IE5.5+)
arguments.caller Reference to the function that invoked the current function. This property is deprecated. (N3, IE4+)
arguments.length The number of arguments that were passed to the function. (IE4+ (JScript 2.0+), MOZ, N3+ (JavaScript 1.1+), ECMA Edition 1)
arity Numeric value indicating how many arguments the function expects. This property is deprecated. (N4+, MOZ)
caller Reference to the function that invoked the current function or null if called from the global context. (IE4+ (JScript 2.0+), MOZ, N3+)
constructor Reference to the constructor object that created the object. (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), ECMA Edition 1)
length The number of arguments the function expects to be passed. (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), ECMA Edition 1)
prototype Reference to the object's prototype. (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), ECMA Edition 1)
Methods
apply(thisArg [, argArray]) Invokes the function with the object referenced by thisArg as its context (so references to this in the function reference thisArg). The optional parameter argArray contains the list of parameters to pass to the function as it is invoked. (IE5.5+ (JScript 5.5+), N4.06+ (JavaScript 1.3+), MOZ, ECMA Edition 3)
call(thisArg [, arg1 [, arg2 [, ...]]]) Invokes the function with the object referenced by thisArg as its context (so references to this in the function reference thisArg). The optional parameters argN are passed to the function as it is invoked. (IE5.5+ (JScript 5.5+), N4.06+ (JavaScript 1.3+), MOZ, ECMA Edition 3)
toString() Returns the string version of the function source. The body of built-in and browser objects will typically be represented by the value "[native code]". (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), MOZ, ECMA Edition 1)
valueOf() Returns the string version of the function source. The body of built-in and browser objects will typically be represented by the value "[native code]". (IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), MOZ, ECMA Edition 1)
Support
Supported in IE4+ (JScript 2.0+), N3+ (JavaScript 1.1+), MOZ, ECMAScript Edition 1.
Notes
General examples of functions are found throughout the book, but see Chapter 5 for examples of the advanced aspects of functions and the Function object.
华山资源网 Design By www.eoogi.com
广告合作:本站广告合作请联系QQ:858582 申请时备注:广告合作(否则不回)
免责声明:本站资源来自互联网收集,仅供用于学习和交流,请遵循相关法律法规,本站一切资源不代表本站立场,如有侵权、后门、不妥请联系本站删除!
免责声明:本站资源来自互联网收集,仅供用于学习和交流,请遵循相关法律法规,本站一切资源不代表本站立场,如有侵权、后门、不妥请联系本站删除!
华山资源网 Design By www.eoogi.com
暂无评论...
RTX 5090要首发 性能要翻倍!三星展示GDDR7显存
三星在GTC上展示了专为下一代游戏GPU设计的GDDR7内存。
首次推出的GDDR7内存模块密度为16GB,每个模块容量为2GB。其速度预设为32 Gbps(PAM3),但也可以降至28 Gbps,以提高产量和初始阶段的整体性能和成本效益。
据三星表示,GDDR7内存的能效将提高20%,同时工作电压仅为1.1V,低于标准的1.2V。通过采用更新的封装材料和优化的电路设计,使得在高速运行时的发热量降低,GDDR7的热阻比GDDR6降低了70%。
更新日志
2024年09月21日
2024年09月21日
- 很有多样性:《战锤》首次引入非二元性别角色
- 《少女前线2:追放》项目组将裁员 官方:进一步优化组织结构
- 陈慧琳.2002-闪亮每一天新歌+精选2CD【正东】【WAV+CUE】
- 袁培华.1992-有缘【歌林】【WAV+CUE】
- 王瑞霞.1996-是我太软心【名冠】【WAV+CUE】
- 《谭维维 30首经典流行歌曲精选辑 2CD》[WAV/分轨][1.1GB]
- 《赵传 出道三十年全新大碟 你过得还好吗》[WAV/分轨][460MB]
- 《发烧四大天王 磁性男声HiFi发烧碟 2CD》[WAV/分轨][1GB]
- 黑神话悟空上品鼠司空精魄获取方法一览|上品鼠司空精魄收集攻略
- 《真三国无双:起源》新情报将于9月26日公开,实机演示亮相!
- 黑神话悟空上品鼠禁卫精魄获取方法一览|上品鼠禁卫精魄收集攻略
- 优美的旋律至真的情怀《品茶轻音乐·极品典藏Vol.1CD1》[WAV+CUE]
- 曾嵘《峥嵘岁月DSD(试音碟)》WAV+CUE
- 小提琴天碟AlfredoCampoli坎波利-贝多芬D大调小提琴协奏曲与普罗米修斯作品选FLAC
- 博主称本周游戏业内动荡无比:高价PS5 Pro、Xbox裁员等