掌握 JavaScript 运算符：从基础知识到按位

let x = 5;let y = 3;// unary operatorlet negx = -x; // -5// binary operatorlet sum = x + y; // 8

let firstname = "john";let lastname = "doe";let fullname = firstname + " " + lastname; // "john doe"

let str = "123";let num = +str; // 123console.log(typeof num); // "number"

let result = 2 + 3 * 4; // 14 (multiplication has higher precedence than addition)

let x = 10;let y = 5;x = y; // x is now 5

let x = 10;x += 5; // x is now 15x -= 3; // x is now 12x *= 2; // x is now 24x /= 4; // x is now 6x %= 5; // x is now 1

let x = 5;x++; // x is now 6x--; // x is now 5

let a = 5; // 0101 in binarylet b = 3; // 0011 in binarylet andresult = a & b; // 0001 in binary, which is 1let orresult = a | b; // 0111 in binary, which is 7let xorresult = a ^ b; // 0110 in binary, which is 6let notresult = ~a; // -6 (two's complement of 0101)let leftshift = a > 1; // 0010 in binary, which is 2

let x = (5, 10); // x is 10