var str=[1,2,3,4,5,6]; var ids = str.join(","); alert(ids);运行结果

var str=[1,2,3,4,5,6]; var ids = str.join(","); alert(ids);运行结果为？

A.123456

B.1,2,3,4,5,6

C.1,2,3,4,5,6,

D.1+2+3+4+5+6

正确答案是B