請大神幫我看看，條件句有報錯
<script type="text/javascript">
//第一步把之前的數據寫成一個數組的形式,定義變量為 infos
var infos=new Array(10);
infos[0]="小A","女";
infos[1]="小B","男";
infos[2]="小C","男";
infos[3]="小D","女";
infos[4]="小E","女";
infos[5]="小F","男";
infos[6]="小G","女";
infos[7]="小H","女";
infos[8]="小I","女";
infos[9]="小J","男";
for(var i=0;i<10;i++)
infos[j]=new Array(10);
infos[0]=21,"大一";
infos[1]=23,"大三";
infos[2]=24,"大四";
infos[3]=21,"大一";
infos[4]=22,"大四";
infos[5]=21,"大一";
infos[6]=22,"大二";
infos[7]=20,"大三";
infos[8]=20,"大一";
infos[9]=20,"大三";
for(var j=0;j<10;j++);
infos[i][j]=i+j;
//第一次篩選，找出都是大一的信息
//第二次篩選，找出都是女生的信息
if(infos[i]="女" && infos[j]="大一"；)
{document.write("大一女生的信息:"+ infos[i][j]+ "</br>");
}
</script>
并且這種寫法是否ok？
2020-06-03
for循環的條件后面，我覺得應該是
{循環語句}
你寫的是? ;??
另外覺得你這樣創建數組很累。貼上我的，你看看呢。
<!DOCTYPE?html>
<html?lang="en">
<head>
????<meta?charset="UTF-8">
????<meta?name="viewport"?content="width=device-width,?initial-scale=1.0">
????<title>篩選數據</title>
????<script>
????????var?infos?=?[
????????????['小A','女',21,'大一'],?
????????????['小B','男',23,'大三'],
????????????['小C','男',24,'大四'],?
????????????['小D','女',21,'大一'],
????????????['小E','女',22,'大四'],?
????????????['小F','男',21,'大一'],
????????????['小G','女',22,'大二'],
????????????['小H','女',20,'大三'],
????????????['小I','女',20,'大一'],
????????????['小J','男',20,'大三']
????????];
????????????//第一次篩選，找出都是大一的信息
????????????//switch寫法
????????????for(i?=?0?;i?<?infos.length?;?i++){
????????????????switch(infos[i][3]){
????????????????????case?'大一':
????????????????????document.write('大一的學生有：'+infos[i]+'<br>');
????????????????????break;
????????????????}
????????????};
????????????document.write('<hr>')
????????????//if寫法
????????????for(i?=?0;i<infos.length;i++){
????????????????????if(infos[i][3]=='大一'){
????????????????????????document.write('大一的學生有：'+infos[i]+'<br>')
????????????????????
????????????????}
????????????};
????????????document.write('<hr>')
????????????//第二次篩選上一步得到的數據，找出都是女生的信息
????????????for(i?=?0?;i?<?infos.length?;?i++){
????????????????????if(infos[i][3]?==?'大一'&&?infos[i][1]==?'女'){
????????????????????????document.write('大一學生中的女生有：'+infos[i]+'<br>')
????????????????}
????????????};
????</script>
</head>
<body>
</body>
</html>
2020-06-01
條件句我知道了……要寫兩個等號，然后把分號去掉
if(infos[i]=="女" && infos[j]=="大一")
然后沒有報錯了，可是無法輸出……請問哪兒錯了？