[JS101] 用 JavaScript 一步步打造程式基礎 - 判斷式

Example-5.js

/if,else if,else 判斷式/
var score = 40
if (score >= 70){
	console.log('Perfect!')
}else if (score >= 60){
    console.log('Good!')
}else if (score >= 50){
	console.log('OK!')
}else{
    console.log('See u next time!')
}

/switch case 當條件很多時，可以改用的簡易寫法，但也可以用陣列的方式來取/
var month = 3
switch(month){
	case 1:
	console.log('January')
	break
	case 2:
	console.log('February')
	break
	case 3:
	console.log('March')
	break
	default:
	console.log('Please try again!')
}
var month_result = ['January','February','March']
console.log(month_result[month-1])

/*三元運算子*/
var month = 3
var result = month >= 3 ? console.log('Good!') : console.log('Not good!') 

/*計算BMI*/
var height_cm= 180 
var height = height_cm/100
var weight= 70 
var bmi = weight/(height**2)

console.log ('你的BMI的數值為：'+ bmi.toFixed(2))
if (bmi < 18.5){
	console.log('體重過輕')
}else if (bmi < 24){
    console.log('正常範圍')
}else if (bmi < 27){
	console.log('過重')
}else if (bmi < 30){
	console.log('輕度肥胖')
}else if (bmi < 35){
	console.log('中度肥胖')
}else{
    console.log('重度肥胖')
}