自增 (++)

自增运算符 (++) 将其操作数递增（加1）并返回一个值。

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Syntax

Operator: x++ or ++x

Description

If used postfix, with operator after operand (for example, x++), the increment operator increments and returns the value before incrementing.

If used prefix, with operator before operand (for example, ++x), the increment operator increments and returns the value after incrementing.

Examples

Postfix increment

let x = 3;
y = x++;

// y = 3
// x = 4

Prefix increment

let a = 2;
b = ++a;

// a = 3
// b = 3

Specifications

Browser compatibility

See also

• Addition operator
• Subtraction operator
• Division operator
• Multiplication operator
• Remainder operator
• Exponentiation operator
• Decrement operator
• Unary negation operator
• Unary plus operator