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¥»¸`»¡©ú JavaScript ªº¬O°j°é±Ô­z¡]Loop Statement¡^¡A³o¨Ç±Ô­z¥i¥HÅý¹q¸£¤ÏÂЦa°õ¦æ¬Y¤@¬qµ{¦¡½X¡C

­º¥ý»¡©úªº¬O for °j°é±Ô­z¡A¨ä®æ¦¡©M C »y¨¥ªº for °j°é«ÜÃþ¦ü¡A°ò¥»®æ¦¡¦p¤U¡G

for ([«ü©w¤@­Ó­p¼ÆÅܼƪºªì­È]; [´ú¸Õ¦¡]; [§ó·s­p¼ÆÅܼƪº°Ê§@]) { °j°é¤º³¡±Ô­z } for ±Ô­z·|«ü©w¤@­Ó­p¼ÆÅܼƪºªì­È¡B¤@­Ó±ø¥ó¦¡¡A¥H¤Î¤@­Ó·|§ó·s­p¼ÆÅܼƪº°Ê§@¡C¦b¨C¤@¦¸­n°õ¦æ°j°é¤§«e¡A³£·|§PÂ_±ø¥ó¦¡ªº­È¡C¦pªG±ø¥ó¦¡¬°¯u¡A°j°é¸Ìªºµ{¦¡½X´N·|°õ¦æ¡F¤Ï¤§¡A¦pªG¨S¦³³q¹L¡A´N¤£·|°õ¦æ¡A¨Ãª½±µ¸õ¨ì°j°é¤§«áªº²Ä¤@¦æµ{¦¡½X¡C¦b°õ¦æ°j°é¤§«á¡A´N·|¶i¦æ§ó·s³o­Ó­p¼ÆÅܼƪº°Ê§@¡AµM«á¦A¶}©l¤U¤@­Ó­¡¥N¡C¤U¦C½d¨Ò¨Ï¥Î for °j°é¨Ó¦L¥X 5 ­Ó¨Ì¦¸Åܤjªº ¡uHello world¡I¡v¡G

Example¡]forLoop01.htm¡^¡G

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­ì©lÀÉ¡]forLoop01.htm¡^¡G¡]¦Ç¦â°Ï°ì«ö¨â¤U§Y¥i«þ¨©¡^
<html>
<head>
<meta HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=big5">
</head>

<body>
<h2 align=center>¥Ñ for °j°é¨Ó²£¥Í 5 ­Ó¥Ñ¤pÅܤjªº  "Hello World!"</h2>
<hr>

<script>
// ¥Ñ for °j°é¨Ó²£¥Í 5 ­Ó¥Ñ¤pÅܤjªº  "Hello World!"
for (i=1; i<=5; i++) {
	document.write("Font size = " + i + " ===> ");
	document.write("<font color=green size=" + i + ">Hello World!</font><br>");
}
</script>

<hr>
</body>
</html>

JavaScript ´£¨Ñ¥t¤@ºØ¯S®íÃþ«¬ªº for °j°é¡AºÙ¬° for-in °j°é¡A¥i¥Î©ó³B²z¤@­Óª«¥óªº©Ò¦³ÄݩʡC¦b for-in °j°é¤¤ªº­p¼ÆÅܼƬO¤@­Ó¦r¦ê¡A¦Ó¤£¬O¤@­Ó¼Æ¦r¡A¦¹¦r¦êÅܼƦb¨C¦¸°j°é¥Nªí¤@­Ó¯S©wªºÄݩʦWºÙ¡A¦]¦¹§Ú­Ì¥i¥H¨Ï¥Î¦¹Ãþ°j°é¡A½aÁ|¥X¤@­Óª«¥óªº©Ò¦³©Ê½è¡CÁ|¨Ò¨Ó»¡¡A¨C­Óºô­¶³£¦³¤@­Ó document ª«¥ó¨Ó¥Nªí¦¹ºô­¶¡A¦]¦¹¦b¤U¦C½d¨Ò¤¤¡A§Ú­Ì¨Ï¥Î for-in °j°é¨Ó¦CÁ| document ª«¥óªº©Ò¦³©Ê½è¡G

Example¡]forInLoop01.htm¡^¡G

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­ì©lÀÉ¡]forInLoop01.htm¡^¡G¡]¦Ç¦â°Ï°ì«ö¨â¤U§Y¥i«þ¨©¡^
<html>
<head>
<meta HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=big5">
</head>

<body>
<h2 align=center>¨Ï¥Î for-in °j°é¨Ó¦CÁ| document ª«¥óªºÄÝ©Ê</h2>
<hr>

<script>
// ¦CÁ| document ª«¥ó¤¤ªº©Ò¦³ÄÝ©Ê
for (prop in document)
	document.write("<br>document." + prop + " = " + document[prop]);
</script>

<hr>
</body>
</html>

¥Ñ¤W­zµ{¦¡½X¤]¥i¥H¬Ý¥X¡A§Ú­Ì¥i¥H¨Ï¥Î document.xyz ©Î document["xyz"] ¨Ó¦s¨úÄÝ©Ê xyz¡A±o¨ìªºµ²ªG¬O¬Û¦Pªº¡C

·íµM¡A§Ú­Ì¤]¥i¥H¥ý«Ø¥ß¤@­Óª«¥ó¡A«ü©w¥¦ªºÄݩʩMÄݩʭȫá¡A¦A¥Î for-in °j°é±N©Ò¦³ªºÄݩʭȦC¦L¥X¨Ó¡A¦p¤U¡G

Example¡]forInLoop02.htm¡^¡G

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­ì©lÀÉ¡]forInLoop02.htm¡^¡G¡]¦Ç¦â°Ï°ì«ö¨â¤U§Y¥i«þ¨©¡^
<html>
<head>
<meta HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=big5">
</head>

<body>
<h2 align=center>for-in °j°é</h2>
<hr>

<script>
// «Ø¥ß¨ã¦³¤@¨ÇÄݩʪºª«¥ó¡C
student = new Object();
student.name = "Timmy";
student.age = "25";
student.phone = "575-1114";

// ¦CÁ|ª«¥ó¤¤ªº©Ò¦³ÄÝ©Ê
for (prop in student)
    document.write("<br>student." + prop + " = " + student[prop]);

</script>

<hr>
</body>
</html>

¦b¤W­z½d¨Ò¤¤¡Aprop ÅܼƷ|³Q¤À§O«ü©w¦¨¦r¦ê "name"¡B"age"¡B"phone"¡A¥Nªí¦¹ª«¥óªº©Ê½è¦WºÙ¡AµM«á¦b¸g¥Ñ student[prop] ¨ú±o¤£¦P©Ê½è©Ò¹ïÀ³ªº­È¡C

¥t¤@­Ó±`¥Î¨ìªº°j°é±Ô­z¬O while °j°é¡A¨ä¥ÎªkÃþ¦ü for °j°é¡A°ò¥»®æ¦¡¬°¡G

while (±ø¥ó¦¡) { °j°é¤º³¡±Ô­z } ¥u­n±ø¥ó¦¡¬°¯u¡Awhile °j°éªº¤º³¡±Ô­z´N·|¤ÏÂФ@¦A³Q°õ¦æ¡C¦b¤U¦C½d¨Ò¤¤¡A§Ú­Ì§Q¥Î while °j°é¨Ó¤ÏÂЦL¥XÀH¾÷ÅܼƭȡAª½¨ì©Ò¹J¨ìªºÀH¾÷ÅܼƭȤj©ó 0.8 ¤~°±¤î¡G

Example¡]whileLoop01.htm¡^¡G

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­ì©lÀÉ¡]whileLoop01.htm¡^¡G¡]¦Ç¦â°Ï°ì«ö¨â¤U§Y¥i«þ¨©¡^
<html>
<head>
<meta HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=big5">
</head>

<body>
<h2 align=center>while °j°é</h2>
<hr>

<script>
x=Math.random();	// ²£¥Í¤@­Ó¤¶©ó 0 ©M 1 ¤§¶¡ªº¶Ã¼Æ
while (x<=0.8) {
	document.write("<br>"+x);
	x=Math.random();
}
document.write("<br>"+x);
</script>

<hr>
</body>
</html>

¥t¥~ÁÙ¦³¤@­Ó©M while ¥\¯àÃþ¦üªº°j°é«ü¥O¡AºÙ¬° do-while °j°é¡A¨ä°ò¥»®æ¦¡¦p¤U¡G

do { °j°é¤º³¡±Ô­z } while (±ø¥ó¦¡); while °j°é¬O¥ý§PÂ_±ø¥ó¦¡¡A¦A¨M©w¬O§_°õ¦æ°j°é¤º³¡±Ô­z¡F¦Ó do-while °j°é¬O¥ý°õ¦æ°j°é¤º³¡±Ô­z«á¡A¦A§PÂ_±ø¥ó¦¡¡A¨M©w¬O§_Ä~Äò°õ¦æ°j°é¡A¦]¦¹ do-while °j°é¦Ü¤Ö·|°õ¦æ¤@¦¸°j°é¤º³¡ªºµ{¦¡½X¡C¨Ò¦p§Ú­Ì§Q¥Î do-while °j°é¨Ó¤ÏÂФW¤@­Ó½d¨Ò¡Aµ{¦¡½X·|§ó²¤Æ¤@¨Ç¡G

Example¡]whileLoop02.htm¡^¡G

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<html>
<head>
<meta HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=big5">
</head>

<body>
<h2 align=center>do-while °j°é</h2>
<hr>

<script>
do {
	x=Math.random();	// ²£¥Í¤@­Ó¤¶©ó 0 ©M 1 ¤§¶¡ªº¶Ã¼Æ
	document.write("<br>"+x);
} while (x<=0.8);
</script>

<hr>
</body>
</html>

­Y­n±q°j°é¤¤§Y¨è¸õ¥X¡A¥i¥Î break ±Ô­z¡A¨Ò¦p¦b«e­z¦L¥X¶Ã¼Æªº½d¨Ò¤¤¡A§Ú­Ì¥i¥H§ï¼g¦p¤U¡G

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<head>
<meta HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=big5">
</head>

<body>
<h2 align=center>while °j°é¡Gbreak ªº¨Ï¥Î</h2>
<hr>

<script>
while (1) {
	x=Math.random();	// ²£¥Í¤@­Ó¤¶©ó 0 ©M 1 ¤§¶¡ªº¶Ã¼Æ
	document.write("<br>"+x);
	if (x>0.8)
		break;
}
</script>

<hr>
</body>
</html>

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­ì©lÀÉ¡]whileLoop04.htm¡^¡G¡]¦Ç¦â°Ï°ì«ö¨â¤U§Y¥i«þ¨©¡^
<html>
<head>
<meta HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=big5">
</head>

<body>
<h2 align=center>for °j°é¡Gcontinue ªº¨Ï¥Î</h2>
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<script>
for (i=0; i<100; i++) {
	a=Math.random();	// ²£¥Í¤@­Ó¤¶©ó 0 ©M 1 ¤§¶¡ªº¶Ã¼Æ
	if (a<=0.95)
		continue;
	document.write("<br>"+a);
}
</script>

<hr>
</body>
</html>


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