如何拼接正则表达式

Question

<script>
var n=new Array(".htm",".html",".shtml");
var pattern1 = new RegExp("\\w+\\"+n[0]+"$","gi");
var s1="b.htm",s2="b.xml"
alert(pattern1.test(s1))
alert(pattern1.test(s2))
</script>

Answer 1

<script>
var n=new Array(".htm",".html",".shtml");
//var pattern1 = new RegExp("\\w+\\"+n[0]+"$","gi");
var s1="b.shtml";
var result = false;
for(var i=0;i<n.length;i++)
{
    pattern1 = new RegExp("\\w+\\"+n[i]+"$","gi");
result|=pattern1.test(s1);
}
alert(Boolean(result));
</script>