iframeset嵌套的问题：一层iframeset时可以展开与关闭，增加一层就不行了_html/css

function isShowNav(){alert(window.parent.colsIndex.cols);	if(window.parent.colsIndex.cols == "250,11,*"){	window.parent.colsIndex.cols = "0,11,*";	}else{	window.parent.colsIndex.cols = "250,11,*";	}}

 function isShowNav() { var colsIndex = parent.document.getElementById('colsIndex'); alert(colsIndex.cols); if (colsIndex.cols == "250,11,*") { colsIndex.cols = "0,11,*"; } else { colsIndex.cols = "250,11,*"; } }