javascript簡單的if語句
<!DOCTYPE ?HTML>
<html >
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>函數(shù)</title>
<script type="text/javascript">
function compare(a,b){
//定義函數(shù)
if(a>b){
? ? return a;
}
else if(b>a){
? ? return b;
}
else{
? ? var c= document.write("兩個(gè)值相等")；
? ? return c;
}
}
//函數(shù)體，判斷兩個(gè)整數(shù)比較的三種情況
?
//調(diào)用函數(shù)，實(shí)現(xiàn)下面兩組數(shù)中，返回較大值。
? document.write(" 5 和 4 的較大值是:"+compare(5,4)+"<br>");
? document.write(" 6 和 3 的較大值是:"+compare(6,3));?
</script>
</head>
<body>
</body>
</html>
怎么不跑，除非我把else中的內(nèi)容去掉，我覺得else中合理啊
2015-12-22
?var?c=?document.write("兩個(gè)值相等")；這一行分號錯(cuò)了。改成英文分號即可。
2015-12-22
用typeof c判斷var c= document.write("兩個(gè)值相等")的數(shù)據(jù)類型是undefined,你要搞清document里的方屬性,最好遍歷一下
<script type="text/javascript">
for (var a in document) {
document.write(a+"<br/>");
};
</script>
?
2015-12-22
<!DOCTYPE??HTML> <html?> <head> ????<meta?http-equiv="Content-Type"?content="text/html;?charset=utf-8"?/> ????<title>函數(shù)</title> ????<script?type="text/javascript"> ????????function?compare(a,b){ //定義函數(shù) ????????????if(a>b){ ????????????????return?a; ????????????}else?if(b>a){ ????????????????return?b; ????????????} ????????????else{ ????????????????var?c=?"兩個(gè)值相等";//運(yùn)行發(fā)現(xiàn)';'錯(cuò)誤 ????????????????return?c; ????????????} ????????} ????????//函數(shù)體，判斷兩個(gè)整數(shù)比較的三種情況 ????????//調(diào)用函數(shù)，實(shí)現(xiàn)下面兩組數(shù)中，返回較大值。 ????????document.write("?5?和?4?的較大值是:"+compare(5,4)+"<br>"); ????????document.write("?6?和?3?的較大值是:"+compare(6,3)); ????</script> </head> <body> </body> </html>