jquery遍历三维数组形成的json

$("#user_message").click(function(){
	var obj=this;
	$(".pmassage").slideToggle(function(){
		$.post(show_message,{"user":$(obj).attr("user")},function(data){
			$(".pmassage").html("");
			if (data.pl!="null") {
				$(data.pl).each(function(i){
					if (data.pl[i].pl_at_id=="0") {
						$(".pmassage").append("<div class="imsg"><span><img src=""+data.pl[i].user_head+"" alt="头像"></span><p><a href="javascript:;">"+data.pl[i].pl_plr_name+"</a>回复了<a href=""+data.pl[i].url+""  target="_blank">【"+data.pl[i].nl_key+"】</a></p></div>");
					}else{
						$(".pmassage").append("<div class="imsg"><span><img src=""+data.pl[i].user_head+"" alt="头像"></span><p><a href="javascript:;">"+data.pl[i].pl_plr_name+"</a>回复了<a href=""+data.pl[i].url+""  target="_blank">【"+data.pl[i].at_title+"】</a></p></div>");
					};
				})
			};
			if (data.zan!="null") {
				$(data.zan).each(function(i){
					if (data.zan[i].pl_at_id=="0") {
						$(".pmassage").append("<div class="imsg"><span><img src=""+data.zan[i].user_head+"" alt="头像"></span><p><a href="javascript:;">"+data.zan[i].pl_plr_name+"</a>觉得你在<a href=""+data.zan[i].url+""  target="_blank">【"+data.zan[i].nl_key+"】</a>下的评论很赞</p></div>");
					}else{
						$(".pmassage").append("<div class="imsg"><span><img src=""+data.zan[i].user_head+"" alt="头像"></span><p><a href="javascript:;">"+data.zan[i].pl_plr_name+"</a>觉得你在<a href=""+data.zan[i].url+""  target="_blank">【"+data.zan[i].at_title+"】</a>下的评论很赞</p></div>");
					};
				})
			};
			
		});
		$(".baikeWaper").click(function(){
		$(".pmassage").fadeOut();
		});
	});
});