Jquery判断元素是否包含在数组中$.inArray()

项目中经常会遇到判断一个元素是否包含在数组中，用Jquery的话很简单，代码如下：

		var memberIdArr = new Array();
		var win = art.dialog.open.origin;
		if("Drgo_RP_assessor"==($("#condition").val())){
			win.$("#choice").find("li").each(function(index){
				memberIdArr[index] = $(this).attr("id");
			}); 
		}else{
			win.$("#choiceMaster").find("li").each(function(index){
				memberIdArr[index] = $(this).attr("id");
			}); 
		}
		$(".unchoice_li").each(function(){
			var member = "";
			if($.inArray($(this).find("input").val(), memberIdArr) != -1){
				member = member +"<li class="choice_li" onclick="clickLi(this)">" + $(this).html() + "</li>";
				$(this).remove();
			}
			$("#choice").append(member);
		});

var arr = [ "刘诗诗", "杨幂", "刘亦菲", "周冬雨" ];  
$.inArray("周冬雨", arr);

返回4,如果不包含在数组中,则返回 -1。