JavaScript基础之运算符

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let a1 = 1
let b1 = 2
let c1 = b1 + a1++
console.log(a1, b1, c1);//2,2,3

let a2 = 1
let b2 = 2
let c2 = b2 + ++a2
console.log(a2, b2, c2);//2,2,4

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let a = 0;
let b = 1;
let c = a || b;
console.log(c);//1

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let sex = prompt('您的性别?')
    if (!sex){
        sex="保密"
    }
    console.log(sex);

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let sex = prompt('您的性别?') || "保密"
console.log(sex);

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/*function judge(num) {
    if (num % 2 === 0) {
        return "偶数"
    } else {
        return "奇数"
    }
}*/
function judge(num) {
    return num % 2 === 0 && "偶数" || "奇数"
    //return num % 2 === 0 ? "偶数" : "奇数"
}

console.log(judge(2));//偶数

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if (flag) {
    //...do something 
} else {
    //...do something 
}

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flag && {...do someting} || {...do someting}