--- title: JavaScript リファレンス slug: Web/JavaScript/Reference tags: - Code - ECMAScript - ECMAScript6 - ES6 - JS - JavaScript - Landing page - Reference - es - l10n:priority - programming translation_of: Web/JavaScript/Reference --- {{JsSidebar}} MDN のこの JavaScript の章は、JavaScript 言語についての情報倉庫となっています。詳しくは[このリファレンスについて](/ja/docs/Web/JavaScript/Reference/About)を読んでください。 ## 組み込みオブジェクト [JavaScript の標準組み込みオブジェクト](/ja/docs/Web/JavaScript/Reference/Global_Objects)と、そのメソッドやプロパティです。 ### 値プロパティ - {{JSxRef("globalThis")}} - {{JSxRef("Infinity")}} - {{JSxRef("NaN")}} - {{JSxRef("undefined")}} ### 関数プロパティ - {{JSxRef("Global_Objects/eval", "eval()")}} - {{JSxRef("Global_Objects/isFinite", "isFinite()")}} - {{JSxRef("Global_Objects/isNaN", "isNaN()")}} - {{JSxRef("Global_Objects/parseFloat", "parseFloat()")}} - {{JSxRef("Global_Objects/parseInt", "parseInt()")}} - {{JSxRef("Global_Objects/decodeURI", "decodeURI()")}} - {{JSxRef("Global_Objects/decodeURIComponent", "decodeURIComponent()")}} - {{JSxRef("Global_Objects/encodeURI", "encodeURI()")}} - {{JSxRef("Global_Objects/encodeURIComponent", "encodeURIComponent()")}} ### 基本オブジェクト - {{JSxRef("Object")}} - {{JSxRef("Function")}} - {{JSxRef("Boolean")}} - {{JSxRef("Symbol")}} ### エラーオブジェクト - {{JSxRef("Error")}} - {{JSxRef("EvalError")}} - {{JSxRef("RangeError")}} - {{JSxRef("ReferenceError")}} - {{JSxRef("SyntaxError")}} - {{JSxRef("TypeError")}} - {{JSxRef("URIError")}} - {{JSxRef("AggregateError")}} ### 数値と日付 - {{JSxRef("Number")}} - {{JSxRef("BigInt")}} - {{JSxRef("Math")}} - {{JSxRef("Date")}} ### テキスト処理 - {{JSxRef("String")}} - {{JSxRef("RegExp")}} ### 添字付きコレクション - {{JSxRef("Array")}} - {{JSxRef("Int8Array")}} - {{JSxRef("Uint8Array")}} - {{JSxRef("Uint8ClampedArray")}} - {{JSxRef("Int16Array")}} - {{JSxRef("Uint16Array")}} - {{JSxRef("Int32Array")}} - {{JSxRef("Uint32Array")}} - {{JSxRef("BigInt64Array")}} - {{JSxRef("BigUint64Array")}} - {{JSxRef("Float32Array")}} - {{JSxRef("Float64Array")}} ### キー付きコレクション - {{JSxRef("Map")}} - {{JSxRef("Set")}} - {{JSxRef("WeakMap")}} - {{JSxRef("WeakSet")}} ### 構造化データ - {{JSxRef("ArrayBuffer")}} - {{JSxRef("SharedArrayBuffer")}} - {{JSxRef("DataView")}} - {{JSxRef("Atomics")}} - {{JSxRef("JSON")}} ### メモリー管理 - {{JSxRef("WeakRef")}} - {{JsxRef("FinalizationRegistry")}} ### 制御の抽象化 - {{JSxRef("Promise")}} - {{JSxRef("GeneratorFunction")}} - {{JSxRef("AsyncGeneratorFunction")}} - {{JSxRef("Generator")}} - {{JSxRef("AsyncGenerator")}} - {{JSxRef("AsyncFunction")}} ### リフレクション - {{JSxRef("Reflect")}} - {{JSxRef("Proxy")}} ### 国際化 - {{JSxRef("Intl")}} - {{JSxRef("Global_Objects/Intl/Collator", "Intl.Collator")}} - {{JSxRef("Global_Objects/Intl/DateTimeFormat", "Intl.DateTimeFormat")}} - {{JSxRef("Global_Objects/Intl/DisplayNames", "Intl.DisplayNames")}} - {{JSxRef("Global_Objects/Intl/ListFormat", "Intl.ListFormat")}} - {{JSxRef("Global_Objects/Intl/Locale", "Intl.Locale")}} - {{JSxRef("Global_Objects/Intl/NumberFormat", "Intl.NumberFormat")}} - {{JSxRef("Global_Objects/Intl/PluralRules", "Intl.PluralRules")}} - {{JSxRef("Global_Objects/Intl/RelativeTimeFormat", "Intl.RelativeTimeFormat")}} ### WebAssembly - {{JSxRef("WebAssembly")}} - {{JSxRef("WebAssembly.Module")}} - {{JSxRef("WebAssembly.Instance")}} - {{JSxRef("WebAssembly.Memory")}} - {{JSxRef("WebAssembly.Table")}} - {{JSxRef("WebAssembly.CompileError")}} - {{JSxRef("WebAssembly.LinkError")}} - {{JSxRef("WebAssembly.RuntimeError")}} ## 文 [JavaScript の文と宣言](/ja/docs/Web/JavaScript/Reference/Statements) ### 制御フロー - {{jsxref("Statements/block", "ブロック", "", 1)}} - {{jsxref("Statements/Empty", "空文", "", 1)}} - {{jsxref("Statements/break", "break")}} - {{jsxref("Statements/continue", "continue")}} - {{jsxref("Statements/if...else", "if...else")}} - {{jsxref("Statements/switch", "switch")}} - {{jsxref("Statements/throw", "throw")}} - {{jsxref("Statements/try...catch", "try...catch")}} ### 宣言 - {{jsxref("Statements/var", "var")}} - {{jsxref("Statements/let", "let")}} - {{jsxref("Statements/const", "const")}} ### 関数とクラス - {{jsxref("Statements/function", "function")}} - {{jsxref("Statements/function*", "function*")}} - {{jsxref("Statements/async_function", "async function")}} - {{jsxref("Statements/return", "return")}} - {{jsxref("Statements/class", "class")}} ### 反復処理 - {{jsxref("Statements/do...while", "do...while")}} - {{jsxref("Statements/for", "for")}} - {{jsxref("Statements/for_each...in", "for each...in")}} - {{jsxref("Statements/for...in", "for...in")}} - {{jsxref("Statements/for...of", "for...of")}} - {{jsxref("Statements/for-await...of", "for await...of")}} - {{jsxref("Statements/while", "while")}} ### その他 - {{jsxref("Statements/debugger", "debugger")}} - {{jsxref("Statements/export", "export")}} - {{jsxref("Statements/import", "import")}} - {{jsxref("Statements/label", "label")}} - {{jsxref("Statements/with", "with")}} ## 式と演算子 [JavaScript の式と演算子](/ja/docs/Web/JavaScript/Reference/Operators) ### 主要な式 - {{JSxRef("Operators/this", "this")}} - {{JSxRef("Operators/function", "function")}} - {{JSxRef("Operators/class", "class")}} - {{JSxRef("Operators/function*", "function*")}} - {{JSxRef("Operators/yield", "yield")}} - {{JSxRef("Operators/yield*", "yield*")}} - {{JSxRef("Operators/async_function", "async function")}} - {{JSxRef("Operators/await", "await")}} - {{JSxRef("Global_Objects/Array", "[]")}} - {{JSxRef("Operators/Object_initializer", "{}")}} - {{JSxRef("Global_Objects/RegExp", "/ab+c/i")}} - {{JSxRef("Operators/Grouping", "( )")}} - {{JSxRef("null")}} ### 左辺式 - {{JSxRef("Operators/Property_accessors", "プロパティアクセサー", "", 1)}} - {{JSxRef("Operators/Optional_chaining", "?. (オプショナルチェイニング)", "", 1)}} - {{JSxRef("Operators/new", "new")}} - {{JSxRef("Operators/new%2Etarget", "new.target")}} - {{JSxRef("Statements/import%2Emeta", "import.meta")}} - {{JSxRef("Operators/super", "super")}} - {{JSxRef("Operators/Spread_syntax", "...obj")}} ### インクリメント & デクリメント - {{JSxRef("Operators/Increment", "A++")}} - {{JSxRef("Operators/Decrement", "A--")}} - {{JSxRef("Operators/Increment", "++A")}} - {{JSxRef("Operators/Decrement", "--A")}} ### 単項演算子 - {{JSxRef("Operators/delete", "delete")}} - {{JSxRef("Operators/void", "void")}} - {{JSxRef("Operators/typeof", "typeof")}} - {{JSxRef("Operators/Unary_plus", "+")}} - {{JSxRef("Operators/Unary_negation", "-")}} - {{JSxRef("Operators/Bitwise_NOT", "~")}} - {{JSxRef("Operators/Logical_NOT", "!")}} ### 算術演算子 - {{JSxRef("Operators/Addition", "+")}} - {{JSxRef("Operators/Subtraction", "-")}} - {{JSxRef("Operators/Division", "/")}} - {{JSxRef("Operators/Multiplication", "*")}} - {{JSxRef("Operators/Remainder", "%")}} - {{JSxRef("Operators/Exponentiation", "**")}} ### 関係演算子 - {{JSxRef("Operators/in", "in")}} - {{JSxRef("Operators/instanceof", "instanceof")}} - {{JSxRef("Operators/Less_than", "<")}} - {{JSxRef("Operators/Greater_than", ">")}} - {{JSxRef("Operators/Less_than_or_equal", "<=")}} - {{JSxRef("Operators/Greater_than_or_equal", ">=")}} ### 等価演算子 - {{JSxRef("Operators/Equality", "==")}} - {{JSxRef("Operators/Inequality", "!=")}} - {{JSxRef("Operators/Strict_equality", "===")}} - {{JSxRef("Operators/Strict_inequality", "!==")}} ### ビットシフト演算子 - {{JSxRef("Operators/Left_shift", "<<")}} - {{JSxRef("Operators/Right_shift", ">>")}} - {{JSxRef("Operators/Unsigned_right_shift", ">>>")}} ### バイナリービット演算子 - {{JSxRef("Operators/Bitwise_AND", "&")}} - {{JSxRef("Operators/Bitwise_OR", "|")}} - {{JSxRef("Operators/Bitwise_XOR", "^")}} ### バイナリー論理演算子 - {{JSxRef("Operators/Logical_AND", "&&")}} - {{JSxRef("Operators/Logical_OR", "||")}} - {{JSxRef("Operators/Nullish_coalescing_operator", "??")}} ### 条件 (三項) 演算子 - {{JSxRef("Operators/Conditional_Operator", "(condition ? ifTrue : ifFalse)")}} ### 代入演算子 - {{JSxRef("Operators/Assignment", "=")}} - {{JSxRef("Operators/Multiplication_assignment", "*=")}} - {{JSxRef("Operators/Exponentiation_assignment", "**=")}} - {{JSxRef("Operators/Division_assignment", "/=")}} - {{JSxRef("Operators/Remainder_assignment", "%=")}} - {{JSxRef("Operators/Addition_assignment", "+=")}} - {{JSxRef("Operators/Subtraction_assignment", "-=")}} - {{JSxRef("Operators/Left_shift_assignment", "<<=")}} - {{JSxRef("Operators/Right_shift_assignment", ">>=")}} - {{JSxRef("Operators/Unsigned_right_shift_assignment", ">>>=")}} - {{JSxRef("Operators/Bitwise_AND_assignment", "&=")}} - {{JSxRef("Operators/Bitwise_XOR_assignment", "^=")}} - {{JSxRef("Operators/Bitwise_OR_assignment", "|=")}} - {{JSxRef("Operators/Logical_AND_assignment", "&&=")}} - {{JSxRef("Operators/Logical_OR_assignment", "||=")}} - {{JSxRef("Operators/Logical_nullish_assignment", "??=")}} - {{JSxRef("Operators/Destructuring_assignment", "[a, b] = [1, 2]")}} - {{JSxRef("Operators/Destructuring_assignment", "{a, b} = {a:1, b:2}")}} ### カンマ演算子 - {{JSxRef("Operators/Comma_Operator", ",")}} ## 関数 この節では、 [JavaScript の関数](/ja/docs/Web/JavaScript/Reference/Functions)を使用してアプリケーションを開発する方法を説明します。 - [`arguments`](/ja/docs/Web/JavaScript/Reference/Functions/arguments) - [アロー関数](/ja/docs/Web/JavaScript/Reference/Functions/Arrow_functions) - [デフォルト引数](/ja/docs/Web/JavaScript/Reference/Functions/Default_parameters) - [残余引数](/ja/docs/Web/JavaScript/Reference/Functions/rest_parameters) ## 追加のリファレンスページ - [字句文法](/ja/docs/Web/JavaScript/Reference/Lexical_grammar) - [データ型とデータ構造](/ja/docs/Web/JavaScript/Data_structures) - [Strict モード](/ja/docs/Web/JavaScript/Reference/Strict_mode) - [非推奨の機能](/ja/docs/Web/JavaScript/Reference/Deprecated_and_obsolete_features)