layer中获取iFrame中的数据

	layer.open({
		  type: 2,
		  title: '编辑音乐',
		  shadeClose: false,
		  shade: 0.8,
		  btnAlign: 'c',
		  area: ['480px', '315px'],
		 btn:['保存修改','取消修改'],
		 yes:function(index,layero){
			var form = $(layero).find("iframe")[0].contentWindow.document.getElementById("editForm")
		 },
		 btn2:function(index,layero){
			 
		 },
		  content: [getActionUrlPrefix()+"toEditWin?model.mlId="+mlId, 'no']
		});