想要做张树形展开，但是遇到问题了，这该怎么解决啊？
代码1：function ExpandCollapse1( el ){ var tr = el.parentElement.parentElement; var tbl = tr.parentElement.parentElement; el.src = "../ags/images/expand_" + ( el.src.index...显示全部代码1：function ExpandCollapse1( el ){ var tr = el.parentElement.parentElement; var tbl = tr.parentElement.parentElement; el.src = "../ags/images/expand_" + ( el.src.index...显示全部
