处理随机分配人数问题

TEAMModelOS/Controllers/Common/ExamController.cs

@@ -1573,7 +1573,7 @@ namespace TEAMModelOS.Controllers
                     {
                         recs.Add(new { stuId = rcd.Name.ToString(), ans = value });
                     }
-                    else
+                    if (string.IsNullOrEmpty(tmdId.ToString())) 
                     {
                         all.Add(new { stuId = rcd.Name.ToString(), ans = value });
                     }
@@ -1598,6 +1598,9 @@ namespace TEAMModelOS.Controllers
                     }
                     else
                     {
+                        if (all.Count == 0) {
+                            return Ok(new { msg = "暂无可选学生" });
+                        }
                         //随机选取一名学生打分
                         Random random = new Random();
                         int n = random.Next(all.Count);