Javascript ?? ??? ???
???
?? ???? ???? ??? ???
?? ?? i++; a+b ??? ??????
?? ???: ?? ???
?? ++ ? ??--
?? ?? ??? ? ???? ??? ? ????.?? ??? ???:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>運算符</title> </head> <script type="text/javascript"> var box=100; box++; //box--; //++box; //--box; document.write(box); </script> <body> </body> </html>
?? ??, ?? 101 ?? ?? ?? 101
?? ??, ?? 99 ?? ?? ?? 99
??: ?? ??? ?? ??? ??
var box=100;
//age = ++box; ??>
//= box ++; //?? ??? age(age=100)? ??? ?? ?? //age = --box //?? ??? 99? ?? ?? ?? age? ??//= box -- //age age=100? ?? ?? ?? ??? ??+ - ???var box=100;
+box; //??
-box //??
??? ??(+)?? ?? ?? ??
?? ??? ??
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>一元運算符</title> </head> <script type="text/javascript"> var box="89"; alert(typeof +box); //如果沒有加號，是string類型，有加號則是number類型 </script> <body> </body> </html>
?? ???
???(+ ) <!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>算術(shù)運算符</title>
</head>
<script type="text/javascript">
var a = 10;
var b = 15;
var c = a+b;
document.write(c);
</script>
<body>
</body>
</html>
????(-)<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>算術(shù)運算符</title>
</head>
<script type="text/javascript">
var a = 10;
var b = 15;
var c = a-b;
document.write(c);
</script>
<body>
</body>
</html>
???(*) ???
???(/)???
???(%)<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>算術(shù)運算符</title>
</head>
<script type="text/javascript">
var a = 10;
var b = 15;
var c = a*b;
document.write(c);
</script>
<body>
</body>
</html>
?? ???
?? ??? ?? ??: ??? ?? ?? >
?? ???
??: ??? 1 ? ??? 2: ??? 3 
?:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>算術(shù)運算符</title> </head> <script type="text/javascript"> var a = 15; var b = 15; var c = a/b; document.write(c); </script> <body> </body> </html>??: ??? 1? true?? ?? ??? ??? 2??, ??? ??? ??? 3???. ?? ?? x=5;?? 1? ??? ???? ??>
? ?? ????. &&(??? ??? ????? true? ?) x=2;y=6; x&&y>6; ?? time, x, y? 6?? ? ?? ??? ????? ??? false; || (?? ? ???? ???? true) x=2;y=6; x||y>6 ; ??, x, y ? ??? ??? ????? ??? ????. ; !(take ??? ??? ??? ????. ??? false? ???, false?? true? ????.) x=5;y=8 ; !(x>y); ?? x? y?? ?? ?????. false? ??? false???. ??? ???? ??? ?? + <!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>算術(shù)運算符</title>
</head>
<script type="text/javascript">
var a = 15;
var b = 5;
var c = a%b;
document.write(c);
</script>
<body>
</body>
</html>
