x['a1']=true;
x['a2']=true;
<script language="JavaScript">
var x={};
x['a']=1;
x['b']=1;
for(var i in x)alert(i)
delete x['b'];
for(var i in x)alert(i)
</script>
x['a2']=true;
<script language="JavaScript">
var x={};
x['a']=1;
x['b']=1;
for(var i in x)alert(i)
delete x['b'];
for(var i in x)alert(i)
</script>
解决方案 »
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