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  1. Tecnologia Web para desenvolvedores
  2. JavaScript
  3. Referência JavaScript
  4. Operadores
  5. Bitwise AND (&)
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Bitwise AND (&)

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since julho de 2015.

O operador bitwise AND (&) retorna 1 em cada posição do bit em que os bits corrrespondentes de ambos os operandos são 1.

In this article

Experimente

const a = 5; // 00000000000000000000000000000101 const b = 3; // 00000000000000000000000000000011 console.log(a & b); // 00000000000000000000000000000001 // Expected output: 1

Sintaxe

js
a & b

Descrição

Os operandos são convertidos em inteiros de 32 bits e expressos por uma série de bits (zeros e uns). Números com mais de 32 bits têm seus bits mais significativos descartados. Por exemplo, o seguinte inteiro com mais de 32 bits será convertido em um de 32 bits inteiro:

Antes: 11100110111110100000000000000110000000000001 Depois: 10100000000000000110000000000001

Cada bit no primeiro operando é emparelhado com o bit correspondente no segundo operando: primeiro bit para o primeiro bit , segundo bit para o segundo bit, e assim por diante.

O operador é aplicado a cada par de bits e o resultado é construído em bitwase.

A tabela verdade para a operação AND é:

a b a AND b
0 0 0
0 1 0
1 0 0
1 1 1
9 (base 10) = 00000000000000000000000000001001 (base 2) 14 (base 10) = 00000000000000000000000000001110 (base 2) -------------------------------- 14 & 9 (base 10) = 00000000000000000000000000001000 (base 2) = 8 (base 10)

A operação AND bit a bit (Bitwase) de qualquer número x com 0 produz 0 .

Exemplos

Usando bitwase AND

js
// 5: 00000000000000000000000000000101 // 2: 00000000000000000000000000000010 5 e 2 ; // 0

Especificações

Specification
ECMAScript® 2027 Language Specification
# prod-BitwiseANDExpression

Compatibilidade de navegadores

Enable JavaScript to view this browser compatibility table.

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  1. JavaScript
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  4. Intermediário
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  6. Referências
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  8. Expressões e operadores
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    7. Bitwise AND (&)
    8. Bitwise AND assignment (&=)
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    35. SyntaxError: as declarações da cabeça do laço for-in podem não ter inicializadores
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    92. TypeError: 'caller', 'callee', and 'arguments' properties may not be accessed
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    96. TypeError: "x" is not a function
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    98. TypeError: "x" is read-only
    99. TypeError: already executing generator
    100. TypeError: BigInt value can't be serialized in JSON
    101. TypeError: calling a builtin X constructor without new is forbidden
    102. TypeError: can't access/set private field or method: object is not the right class
    103. TypeError: can't assign to property "x" on "y": not an object
    104. TypeError: can't convert BigInt to number
    105. TypeError: can't convert x to BigInt
    106. TypeError: can't define property "x": "obj" is not extensible
    107. TypeError: can't delete non-configurable array element
    108. TypeError: can't redefine non-configurable property "x"
    109. TypeError: can't set prototype of this object
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    111. TypeError: cannot use 'in' operator to search for 'x' in 'y'
    112. TypeError: class constructors must be invoked with 'new'
    113. TypeError: cyclic object value
    114. TypeError: derived class constructor returned invalid value x
    115. TypeError: getting private setter-only property
    116. TypeError: Initializing an object twice is an error with private fields/methods
    117. TypeError: invalid 'instanceof' operand 'x'
    118. TypeError: invalid Array.prototype.sort argument
    119. TypeError: atribuição inválida para const "x"
    120. TypeError: Iterator/AsyncIterator constructor can't be used directly
    121. TypeError: matchAll/replaceAll must be called with a global RegExp
    122. TypeError: More arguments needed
    123. TypeError: null/undefined has no properties
    124. TypeError: property "x" is non-configurable and can't be deleted
    125. TypeError: Reduce of empty array with no initial value
    126. TypeError: setting getter-only property "x"
    127. TypeError: WeakSet key/WeakMap value 'x' must be an object or an unregistered symbol
    128. TypeError: X.prototype.y called on incompatible type
    129. URIError: malformed URI sequence
    130. Warning: -file- is being assigned a //# sourceMappingURL, but already has one
    131. Warning: unreachable code after return statement
  14. Mais conteúdo
    1. Visão geral das Tecnologias JavaScript
    2. Execution model
    3. Gramática léxica
    4. Protocolos de iteração
    5. Strict mode - Modo estrito
    6. Template literals
    7. Trailing commas
    8. Funcionalidades depreciadas

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