
1͸ֵ

var =ֵֵַ֡

ıpriceֱӵ price*20

ڳп޸ֵ¸ֵprice=100

2alertҪݣ

ڵ
ݿַ֡ʽ

3prompt"ʾ";   

ڸû
ñȥ䷵ֵ var price=prompt("Ʒ۸")ע䷵ֵַ

4ַӷ  "a"+"b" --> "ab"     "㣺"+change --> "㣺800"

5㣨ע  +  ⣩

ǰjsѲıֵԶת֣Ȼ
ıֵ֣õĽNaNnot a number
ֵʽдң㣩һΪַһԶתַӷַӣ10+20--> "1020"

6parseInt() ַת
   parseFloat() ַתС

parseInt("100.555abc")  -->  100
parseFloat("100.555abc")  --> 100.555
parseFloat( prompt("۸") )

7dwjs룬jsǰ

 <body>

		<script>
		 
			Ĵ

		</script>

	</body>
















