JavaScript条件判断与比较运算示例代码

let a = 5;
if (a > 10) {
  console.log("a is greater than 10");
} else {
  console.log("a is not greater than 10");
}

let b = "red";
switch (b) {
  case "red":
    console.log("The color is red");
    break;
  case "blue":
    console.log("The color is blue");
    break;
  default:
    console.log("The color is neither red nor blue");
}

let c = 5;
let d = (c > 10) ? "c is greater than 10" : "c is not greater than 10";
console.log(d);

let a = 5;
let b = "5";
console.log(a == b); // true

let a = 5;
let b = "5";
console.log(a === b); // false

let a = 5;
let b = "5";
console.log(a != b); // false

let a = 5;
let b = "5";
console.log(a !== b); // true

let a = 5;
let b = 10;
console.log(a > b); // false
console.log(a < b); // true
console.log(a >= b); // false
console.log(a <= b); // true

let c = 5;
let d = "5";
console.log(Object.is(c, d)); // false

let e = [1, 2, 3];
let f = [1, 2, 3];
console.log(jsON.stringify(e) === JSON.stringify(f)); // true

let g = {a: 1, b: 2};
let h = {b: 2, a: 1};
console.log(_.isEqual(g, h)); // true

let obj = new Object();
console.log(obj instanceof Object); // true
console.log(obj instanceof Array); // false

let obj = {a:1,b:2};
console.log("a" in obj); // true
console.log("c" in obj); // false