Javascript ?? ???? ?? ?
???
for ??
for (?1;?2;?3)
???
}
? 1(?? ??)? ???? ?? ?????. ? 2? ??(?? ??) ?? ??? ?????. ? 3? ??(?? ??)? ??? ? ?????.
?? ?? ??? ?????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>循環(huán)語句 for 循環(huán)</title>
</head>
<script type="text/javascript">
sum= 0;
for(var i=1;i<=10;i++){
sum = sum + i;
}
document.write(sum);
</script>
<body>
</body>
</html>? ??? 1?? 10??? ?? ?????.
?? ???? ????. i? ? ??
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>循環(huán)語句 for 循環(huán)</title>
</head>
<script type="text/javascript">
for(var i=1;i<=10;i++){
document.write("第"+i+"天<br>");
}
</script>
<body>
</body>
</html>??? ?? ｉ? ?? 1?? 10?? ?????. ?? ???,
while ??
while(condition){ ?? ?? ??; }?:<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>循環(huán)語句 while 循環(huán)</title>
</head>
<script type="text/javascript">
var i=1;
while(i<10){
document.write("php 中文網(wǎng)<br>");
i++;
}
</script>
<body>
</body>
</html>??: ??? ??? ???? ???. ?? ?? ??? ???? ? i++? ?????. ??? ??? i++? ??? i=1? ?? ?? i<10? ????? ??? ?? ?????.??? ?????. ?? ?????while ??? ???? ? ?? ?? ??? ?????. 1-10? ?? ?????.<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>循環(huán)語句 while 循環(huán)</title>
</head>
<script type="text/javascript">
var i = 1;
var sum = 0;
while(i<=10){
sum = sum + i;
i++;
}
document.write(sum);
</script>
<body>
</body>
</html>? ????? ??? 1?? 10? ?? ?????: while ??? ??? ?? ???? ????. ??? ???? ?? ?????.
? ??? ?? i? ???? 1???. ?? ??? ????? ??? ?????. ??? ?? ??? ???? ??? ?? ???? ??????. ??> ?? ??, ?? ???? ???? i++? ???? ?? ?? ???? ?? ??? ?????.do....while ??
do{
}while(??);?? ??? ???????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>循環(huán)語句 do....while 循環(huán)</title>
</head>
<script type="text/javascript">
var i = 11;
do{
document.write(i+'次');
i++;
}while(i<10);
</script>
<body>
</body>
</html>?? ??? ?? i? ?? ?? 11?? ?? ??? ???? 11? ??? ? i++? ???? ???. ?? i? ?? 12??, ??? ???? ???? ???? ???? ??????. ??: do while ??? ???? ? ?? ??????.
???? do while? ???? 1?? 10??? ?? ????. ??? ??? ????:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>循環(huán)語句 do....while 循環(huán)</title>
</head>
<script type="text/javascript">
var sum = 0;
var i = 1;
do{
sum = sum + i ;
i++;
}while(i<=10)
document.write(sum);
</script>
<body>
</body>
</html>?? ? ??
break ?? ??? ???? ? ?????.
continue? ???? ??? ???? ? ?????. ??? switch??break ?? ??? ?? ????. ???? ???? ?? <!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>break</title>
</head>
<script type="text/javascript">
for(var i=1;i<=10;i++){
if(i==5){
//break;
continue;
}
document.write(i+"<br>");
}
</script>
<body>
</body>
</html> ??? ???? break? ???? ??? ??? ? ????. ?. ???
break i? ??? 5? ??? ???? ?? ????? 4?? ?????.
continue i? 5? ??? ???? ?????. ??? ?? ?????. ?? ??? ?? 5? ?? ?? ?????. 2? ?? ???? ????
