JavaScript 指南會讓您了解如何使用 JavaScript 並給您這個語言的概觀。若您需要語言功能詳細資訊請參考 JavaScript 參考文件。
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JavaScript 指南
相關主題
- JavaScript
- Tutorials:
-
JavaScript Guide
- Introduction
- Grammar and types
- Control flow and error handling
- Loops and iteration
- Functions
- Expressions and operators
- Numbers and dates
- Text formatting
- Regular expressions
- Indexed collections
- Keyed collections
- Working with objects
- Details of the object model
- Using promises
- Iterators and generators
- Meta programming
- References:
-
Built-in objects
- Array
- ArrayBuffer
- AsyncFunction [Translate]
- Atomics [Translate]
- BigInt [Translate]
- Boolean
- DataView
- Date
- Error
- EvalError [Translate]
- Float32Array [Translate]
- Float64Array [Translate]
- Function
- Generator [Translate]
- GeneratorFunction [Translate]
- Infinity
- Int16Array [Translate]
- Int32Array [Translate]
- Int8Array [Translate]
- InternalError [Translate]
- Intl [Translate]
- Intl.Collator [Translate]
- Intl.DateTimeFormat [Translate]
- Intl.ListFormat [Translate]
- Intl.NumberFormat [Translate]
- Intl.PluralRules [Translate]
- Intl.RelativeTimeFormat [Translate]
- JSON
- Map
- Math
- NaN
- Number
- Object
- Promise
- Proxy
- RangeError [Translate]
- ReferenceError [Translate]
- Reflect
- RegExp [Translate]
- Set
- SharedArrayBuffer [Translate]
- 字串
- Symbol [Translate]
- SyntaxError [Translate]
- TypeError [Translate]
- TypedArray
- URIError [Translate]
- Uint16Array [Translate]
- Uint32Array [Translate]
- Uint8Array [Translate]
- Uint8ClampedArray [Translate]
- WeakMap [Translate]
- WeakSet [Translate]
- WebAssembly [Translate]
- decodeURI() [Translate]
- decodeURIComponent() [Translate]
- encodeURI() [Translate]
- encodeURIComponent() [Translate]
- escape() [Translate]
- eval() [Translate]
- isFinite() [Translate]
- isNaN()
- null
- parseFloat() [Translate]
- parseInt()
- undefined
- unescape() [Translate]
- uneval() [Translate]
-
Expressions & operators
- Arithmetic operators [Translate]
- Array comprehensions [Translate]
- Assignment operators [Translate]
- Bitwise operators [Translate]
- 逗號運算子
- 比較運算子
- Conditional (ternary) operator [Translate]
- 解構賦值
- Expression closures [Translate]
- Generator comprehensions [Translate]
- Grouping operator [Translate]
- Legacy generator function expression [Translate]
- Logical operators [Translate]
- Object initializer
- 運算子優先序
- Pipeline operator [Translate]
- Property accessors [Translate]
- Spread syntax [Translate]
- async function expression
- await
- class expression [Translate]
- delete operator [Translate]
- function expression [Translate]
- function* expression [Translate]
- in operator [Translate]
- instanceof [Translate]
- new operator [Translate]
- new.target [Translate]
- super [Translate]
- this
- typeof
- void operator [Translate]
- yield [Translate]
- yield* [Translate]
-
Statements & declarations
- Legacy generator function [Translate]
- async function
- 區塊
- break
- class [Translate]
- const
- continue [Translate]
- debugger
- default [Translate]
- do...while [Translate]
- empty [Translate]
- export
- for [Translate]
- for await...of [Translate]
- for each...in [Translate]
- for...in
- for...of [Translate]
- function declaration [Translate]
- function*
- if...else
- import
- import.meta [Translate]
- label [Translate]
- let
- return
- switch [Translate]
- throw
- try...catch [Translate]
- var
- while [Translate]
- with [Translate]
-
Errors
- Error: Permission denied to access property "x" [Translate]
- InternalError: too much recursion
- RangeError: argument is not a valid code point [Translate]
- RangeError: invalid array length [Translate]
- RangeError: invalid date [Translate]
- RangeError: precision is out of range [Translate]
- RangeError: radix must be an integer [Translate]
- RangeError: repeat count must be less than infinity [Translate]
- RangeError: repeat count must be non-negative [Translate]
- ReferenceError: "x" is not defined
- ReferenceError: assignment to undeclared variable "x" [Translate]
- ReferenceError: can't access lexical declaration`X' before initialization [Translate]
- ReferenceError: deprecated caller or arguments usage [Translate]
- ReferenceError: invalid assignment left-hand side [Translate]
- ReferenceError: reference to undefined property "x" [Translate]
- SyntaxError: "0"-prefixed octal literals and octal escape seq. are deprecated [Translate]
- SyntaxError: "use strict" not allowed in function with non-simple parameters [Translate]
- SyntaxError: "x" is a reserved identifier [Translate]
- SyntaxError: JSON.parse: bad parsing [Translate]
- SyntaxError: Malformed formal parameter [Translate]
- SyntaxError: Unexpected token [Translate]
- SyntaxError: Using //@ to indicate sourceURL pragmas is deprecated. Use //# instead [Translate]
- SyntaxError: a declaration in the head of a for-of loop can't have an initializer [Translate]
- SyntaxError: applying the 'delete' operator to an unqualified name is deprecated [Translate]
- SyntaxError: for-in loop head declarations may not have initializers [Translate]
- SyntaxError: function statement requires a name [Translate]
- SyntaxError: identifier starts immediately after numeric literal [Translate]
- SyntaxError: illegal character [Translate]
- SyntaxError: invalid regular expression flag "x" [Translate]
- SyntaxError: missing ) after argument list [Translate]
- SyntaxError: missing ) after condition [Translate]
- SyntaxError: missing : after property id [Translate]
- SyntaxError: missing ; before statement [Translate]
- SyntaxError: missing = in const declaration [Translate]
- SyntaxError: missing ] after element list [Translate]
- SyntaxError: missing formal parameter [Translate]
- SyntaxError: missing name after . operator [Translate]
- SyntaxError: missing variable name [Translate]
- SyntaxError: missing } after function body [Translate]
- SyntaxError: missing } after property list
- SyntaxError: redeclaration of formal parameter "x"
- SyntaxError: return not in function
- SyntaxError: test for equality (==) mistyped as assignment (=)? [Translate]
- SyntaxError: unterminated string literal [Translate]
- TypeError: "x" has no properties
- TypeError: "x" is (not) "y"
- TypeError: "x" is not a constructor [Translate]
- TypeError: "x" is not a function
- TypeError: "x" is not a non-null object [Translate]
- TypeError: "x" is read-only [Translate]
- TypeError: 'x' is not iterable [Translate]
- TypeError: More arguments needed [Translate]
- TypeError: Reduce of empty array with no initial value [Translate]
- TypeError: can't access dead object [Translate]
- TypeError: can't access property "x" of "y" [Translate]
- TypeError: can't define property "x": "obj" is not extensible [Translate]
- TypeError: can't delete non-configurable array element [Translate]
- TypeError: can't redefine non-configurable property "x" [Translate]
- TypeError: cannot use 'in' operator to search for 'x' in 'y' [Translate]
- TypeError: cyclic object value [Translate]
- TypeError: invalid 'instanceof' operand 'x' [Translate]
- TypeError: invalid Array.prototype.sort argument [Translate]
- TypeError: invalid arguments [Translate]
- TypeError: invalid assignment to const "x" [Translate]
- TypeError: property "x" is non-configurable and can't be deleted [Translate]
- TypeError: setting getter-only property "x" [Translate]
- TypeError: variable "x" redeclares argument [Translate]
- URIError: malformed URI sequence [Translate]
- Warning: -file- is being assigned a //# sourceMappingURL, but already has one [Translate]
- Warning: 08/09 is not a legal ECMA-262 octal constant [Translate]
- Warning: Date.prototype.toLocaleFormat is deprecated [Translate]
- Warning: JavaScript 1.6's for-each-in loops are deprecated [Translate]
- Warning: String.x is deprecated; use String.prototype.x instead [Translate]
- Warning: expression closures are deprecated [Translate]
- Warning: unreachable code after return statement [Translate]
- X.prototype.y called on incompatible type [Translate]
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New in JavaScript
- ECMAScript 2015 support in Mozilla [Translate]
- ECMAScript 5 support in Mozilla [Translate]
- ECMAScript Next support in Mozilla [Translate]
- Firefox JavaScript changelog [Translate]
- New in JavaScript 1.1
- New in JavaScript 1.2
- New in JavaScript 1.3
- New in JavaScript 1.4
- New in JavaScript 1.5
- JavaScript 1.6 新鮮事
- JavaScript 1.7 新鮮事
- JavaScript 1.8 新鮮事
- JavaScript 1.8.1 新鮮事
- New in JavaScript 1.8.5
- Documentation:
-
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