解決ajax傳過來的值后臺接收不到的問題

function confirmCourseSystem(){
	var findAllTrainProgramNameId = $("#findAllTrainProgramNameId").val();
	if(findAllTrainProgramNameId==null || findAllTrainProgramNameId==""){
	window.alertx("請選擇培訓方案！");
	return false;
	}
	var courseSystemId = $('#CourseSystemList').val();
	alertx(courseSystemId);
	$.ajax({
	type: "POST",
	url: "${ctx}/teach/teachDistribute/getCourseSystemNameById",
	data: {
	"CourseSystemId": $('#CourseSystemList').val()
	},
	success:function(CourseSystemListName){
	$('#CourseSystemBody').html("");
	for(var i=0; i<CourseSystemListName.length; i++){
	$("#CourseSystemBody").append("<tr><td>"+CourseSystemListName[i] +"</td><td>課程體系</td><td>無</td></tr>");
	}
	},
	error:function(){
	alertx("error");
	}
	});
	}

//添加下發-確認選擇，根據CourseSystemId獲得CourseSystemName
	@ResponseBody
	@RequestMapping(value = "getCourseSystemNameById")
	public List<String> getCourseSystemNameById(@RequestParam(required = false) String CourseSystemId, HttpServletRequest request){
	logger.debug("==Evan==CourseSystemId: "+ CourseSystemId);
	logger.debug("==Evan==CourseSystemId2 :"+request.getParameter("CourseSystemId"));
	List<String> CourseSystemListName = new ArrayList<>();
	if(CourseSystemId==null || CourseSystemId.equals("")){
	CourseSystemListName = null;
	}else {
	String[] CourseSystemListId = CourseSystemId.split(",");
	for (String aCourseSystemListId : CourseSystemListId) {
	CourseSystemListName.add(resourceCoursesystemService.get(aCourseSystemListId).getCoursesystemName());
	}
	}
	return CourseSystemListName;
	}

	$.ajax({
	type: "POST",
	url: "${ctx}/teach/teachDistribute/getCourseSystemNameById",
	data: {
	"CourseSystemId": $('#CourseSystemList').val().toString()
	},
	success:function(CourseSystemListName){
	$('#CourseSystemBody').html("");
	for(var i=0; i<CourseSystemListName.length; i++){
	$("#CourseSystemBody").append("<tr><td>"+CourseSystemListName[i] +"</td><td>課程體系</td><td>無</td></tr>");
	}
	},
	error:function(){
	alertx("error");
	}
	});