update。

TEAMModelOS/Controllers/School/SchoolController.cs

@@ -1654,7 +1654,7 @@ namespace TEAMModelOS.Controllers
                                 }
                                 else
                                 {
-                                    tch = teacherImport.teachers.Find(t =>  !string.IsNullOrWhiteSpace(x.id) &&  t.id.Equals(x.id));
+                                    tch = teacherImport.teachers.Find(t =>  !string.IsNullOrWhiteSpace(x.id) && !string.IsNullOrWhiteSpace(t.id) &&  t.id.Equals(x.id));
                                 }
                                 if (tch != null)
                                 {