动态路由接收前台传值

前台JS 代码
function ExportStudent() {
    var selectId = $("#selectId").val();
    var gradeId = $("#gradeId").val();
    var classId = $("#classId").val();    
    var courseId = $("#courseId").val(); 
    var currentCount = parseInt($("#totalnum").html());
    if (currentCount > 0) {
        window.location.href = "/EnrollResult/ExportExcel/" + selectId + "/" + gradeId + "/" + classId + "/" + courseId;
        //alert("/EnrollResult/ExportExcel/" + selectId + "/" + gradeId + "/" + classId + "/" + courseId);
    }
    else {
        showErrorTips("当前查询条件下没有可导出的选课信息");
    }
} 

　　后台代码

当参数classid 为空，courseId 不为空时，后台查不到数据，经断点跟踪发现 后台路由结束值时，classId接到得是courseId的值，因此查不到数据

查找原因：

输出 前台url 地址  

 发现classId 为空时，courseId成为第三个参数，

解决办法：判断classId是否为空，给classId赋值，后台做判断。

function ExportStudent() {
    var selectId = $("#selectId").val();
    var gradeId = $("#gradeId").val();
    var classId = $("#classId").val();
    if (classId == "")
    { classId = 1;}
    var courseId = $("#courseId").val(); 
    var currentCount = parseInt($("#totalnum").html());
    if (currentCount > 0) {
        window.location.href = "/EnrollResult/ExportExcel/" + selectId + "/" + gradeId + "/" + classId + "/" + courseId;
        //alert("/EnrollResult/ExportExcel/" + selectId + "/" + gradeId + "/" + classId + "/" + courseId);
    }
    else {
        showErrorTips("当前查询条件下没有可导出的选课信息");
    }
}