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第三章 創(chuàng)建表達式
1.使用算術(shù)運算符
<script>
var1=12
var2=10
varadd=var1+var2
varsub=var1-var2
varmult=var1*var2
vardiv=var1/var2
varmod=var1%var2
document.write("數(shù)據(jù)1是："+var1+"<br>")
document.write("數(shù)據(jù)2是："+var2+"<br>")
document.write("數(shù)據(jù)相加是："+varadd+"<br>")
document.write("數(shù)據(jù)相減是："+varsub+"<br>")
document.write("數(shù)據(jù)相乘是："+varmult+"<br>")
document.write("數(shù)據(jù)相除是："+vardiv+"<br>")
document.write("數(shù)據(jù)相除取余數(shù)是："+varmod+"<br>")
</script>
2.遞增變量和遞減變量
<script>
days=1
document.write("輸出變量"+days+"<br>")
days++
document.write("遞增后變量變?yōu)椋?+days)
</script>
3.創(chuàng)建比較表達式
<script>
daysofmonth=28
if(daysofmonth==28)
month="february"
document.write("days of month:"+daysofmonth+"<br>")
document.write("month:"+month)
</script>
4.創(chuàng)建邏輯表達式
<script>
dayofmonth=28
if(dayofmonth==28 || dayofmonth==29)
month="february"
document.write("days of month:"+dayofmonth+"<br>")
document.write("month:"+month)
</script>
5.使用條件運算符
<script language="javascript">
stomach="hungry";
time="5:00";
(stomach=="hungry"&&time=="5:00") ? eat = "dinner":eat="a snack";
document.write("輸出結(jié)果"+eat);
</script>
6.識別數(shù)字
<script>
var1=24;
(isNaN(var1))?document.write("變量var1"+var1+"不是數(shù)字"):Document.write("變量var1"+var1+"是數(shù)字")
</script>
第四章 控制程序流程
1.使用IF –Else語句
<script>
month="december"
date=25
if(month=="december" && date==25)
document.write("今天是圣誕節(jié),商店關(guān)門")
else
document.write("歡迎,您來商店購物")
</script>
2.使用for 循環(huán)
<script>
for (count=1;count<=10;count++)
document.write("輸出第"+count+"句"+"<br>")
</script>
3.使用while循環(huán)
<script>
count=1
while(count<=15){
document.write("輸出第"+count+"句" +"<br>")
count++}
</script>
4.中斷循環(huán)
<script>
count=1
while(count<=15){
count++
if(count==8)
break;
document.write("輸出第"+count+"句"+"<br>")}
</script>
5.繼續(xù)循環(huán)
<script>
count=1
while(count<=15){
count++
if(count==8)
continue;
document.write("輸出第"+count+"句"+"<br>")}
</script>
6.使用javascript定時器
<script>
function rabbit()
{document.write("輸出語句")
}
</script>
<body onload=window.setTimeout(rabbit(),5000)>
7.設(shè)置定期間隔
<script>
window.setInterval("document.form1.text2.value=document.form1.text1.value",3000)
</script>
<form name=form1>
<input type=text name=text1><br>
<input type=text name=text2><br>
</form>
8.清除超時和間隔
<script>
stop=window.setInterval("document.form1.text2.value=document.form1.text1.value",300)
</script>
<form name=form1>
<input type=text name=text1><br>
<input type=text name=text2><br>
<input type=button name=button1 value=" 清除超時和間隔" onclick=clearInterval(stop)>
</form>
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