diff --git a/src/Jiaowu.Api/Controllers/AttendanceController.cs b/src/Jiaowu.Api/Controllers/AttendanceController.cs
index 573852d..3c25a38 100644
--- a/src/Jiaowu.Api/Controllers/AttendanceController.cs
+++ b/src/Jiaowu.Api/Controllers/AttendanceController.cs
@@ -8,6 +8,7 @@ using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Jiaowu.Api.Infrastructure.Teaching;
 using Microsoft.AspNetCore.Authorization;
@@ -566,7 +567,7 @@ public sealed class AttendanceController(
                 statusLabels.GetValueOrDefault(r.Status, "出勤"), r.Notes
             }).ToList<IReadOnlyList<object?>>());
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"考勤表-{sheetData.TaskNumber}-{sheetData.AttendanceDate:yyyyMMdd}.xlsx");
+            DownloadFileName.Export("考勤表", ".xlsx", sheetData.TaskNumber, sheetData.AttendanceDate.ToString("yyyyMMdd")));
     }
 
     [HttpGet("tasks/{teachingTaskId:guid}/statistics")]
@@ -596,7 +597,7 @@ public sealed class AttendanceController(
         return File(
             bytes,
             ExcelWorkbookHelper.ContentType,
-            $"课程考勤统计-{statistics.Course.TaskNumber}.xlsx");
+            DownloadFileName.Export("课程考勤统计", ".xlsx", statistics.Course.TaskNumber));
     }
 
     [HttpPost("sheets/{id:guid}/submit")]
diff --git a/src/Jiaowu.Api/Controllers/BaseDataExcelController.cs b/src/Jiaowu.Api/Controllers/BaseDataExcelController.cs
index 791f720..7c8bd04 100644
--- a/src/Jiaowu.Api/Controllers/BaseDataExcelController.cs
+++ b/src/Jiaowu.Api/Controllers/BaseDataExcelController.cs
@@ -3,6 +3,7 @@ using Jiaowu.Api.Domain.Common;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -46,7 +47,7 @@ public sealed class BaseDataExcelController(AppDbContext db, IAppCache cache) :
                 "状态填写“启用”或“停用”；是/否字段填写“是”或“否”。",
                 "整批数据会先校验，任一行有误时均不会写入。"
             ]);
-        return File(bytes, ExcelWorkbookHelper.ContentType, $"{KindName(kind)}导入模板.xlsx");
+        return File(bytes, ExcelWorkbookHelper.ContentType, DownloadFileName.Template(KindName(kind), ".xlsx"));
     }
 
     [HttpGet("{kind}/export")]
@@ -56,7 +57,7 @@ public sealed class BaseDataExcelController(AppDbContext db, IAppCache cache) :
         var rows = await GetExportRowsAsync(kind, cancellationToken);
         var bytes = ExcelWorkbookHelper.Create(KindName(kind), headers, rows);
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"{KindName(kind)}-{DateTime.Now:yyyyMMdd-HHmm}.xlsx");
+            DownloadFileName.Export(KindName(kind), ".xlsx"));
     }
 
     [HttpPost("{kind}/import")]
diff --git a/src/Jiaowu.Api/Controllers/CourseSelectionsController.cs b/src/Jiaowu.Api/Controllers/CourseSelectionsController.cs
index df64512..abff537 100644
--- a/src/Jiaowu.Api/Controllers/CourseSelectionsController.cs
+++ b/src/Jiaowu.Api/Controllers/CourseSelectionsController.cs
@@ -6,6 +6,7 @@ using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.CourseSelection;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Graduation;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Jiaowu.Api.Infrastructure.Teaching;
@@ -76,7 +77,7 @@ public sealed class CourseSelectionsController(
             "专业", "行政班", "年级", "修读状态", "修读类型", "选入时间", "退选时间", "免修审批"
         ], rows);
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"修读课程名单-{DateTime.Now:yyyyMMdd-HHmm}.xlsx");
+            DownloadFileName.Export("修读课程名单", ".xlsx"));
     }
 
     [HttpGet("enrollments/students")]
@@ -137,7 +138,7 @@ public sealed class CourseSelectionsController(
             "学号", "姓名", "专业", "行政班", "年级", "修读课程", "在修学分"
         ], rows);
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"学生修读汇总-{DateTime.Now:yyyyMMdd-HHmm}.xlsx");
+            DownloadFileName.Export("学生修读汇总", ".xlsx"));
     }
 
     [HttpGet("rounds")]
@@ -1864,7 +1865,7 @@ public sealed class CourseSelectionsController(
         return File(
             bytes,
             ExcelWorkbookHelper.ContentType,
-            $"教学班名单-{task.TaskNumber}.xlsx");
+            DownloadFileName.Export("教学班名单", ".xlsx", task.TaskNumber));
     }
 
     [HttpGet("offerings/{id:guid}/roster/export.xlsx")]
@@ -1920,7 +1921,7 @@ public sealed class CourseSelectionsController(
                 s.EnrolledAt.ToString("yyyy-MM-dd HH:mm")
             }).ToList<IReadOnlyList<object?>>());
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"选课名单-{offering.TaskNumber}.xlsx");
+            DownloadFileName.Export("选课名单", ".xlsx", offering.TaskNumber));
     }
 
     private IQueryable<CourseSelectionOffering> ScopedOfferings()
diff --git a/src/Jiaowu.Api/Controllers/CoursesExcelController.cs b/src/Jiaowu.Api/Controllers/CoursesExcelController.cs
index 4a5ed8f..1048714 100644
--- a/src/Jiaowu.Api/Controllers/CoursesExcelController.cs
+++ b/src/Jiaowu.Api/Controllers/CoursesExcelController.cs
@@ -4,6 +4,7 @@ using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -51,7 +52,7 @@ public sealed class CoursesExcelController(
         return File(
             bytes,
             ExcelWorkbookHelper.ContentType,
-            "课程库导入模板.xlsx");
+            DownloadFileName.Template("课程库", ".xlsx"));
     }
 
     [HttpGet("export")]
@@ -98,7 +99,7 @@ public sealed class CoursesExcelController(
         return File(
             bytes,
             ExcelWorkbookHelper.ContentType,
-            $"课程库-{DateTime.Now:yyyyMMdd-HHmm}.xlsx");
+            DownloadFileName.Export("课程库", ".xlsx"));
     }
 
     [HttpPost("import")]
diff --git a/src/Jiaowu.Api/Controllers/ExamsController.cs b/src/Jiaowu.Api/Controllers/ExamsController.cs
index bd96d7a..e8968c8 100644
--- a/src/Jiaowu.Api/Controllers/ExamsController.cs
+++ b/src/Jiaowu.Api/Controllers/ExamsController.cs
@@ -6,6 +6,7 @@ using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Exams;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Jiaowu.Api.Infrastructure.Teaching;
 using Microsoft.AspNetCore.Authorization;
@@ -1144,7 +1145,7 @@ public sealed class ExamsController(
         return File(
             bytes,
             ExcelWorkbookHelper.ContentType,
-            $"考场签名单-{FileNamePart(plan.Name)}.xlsx");
+            DownloadFileName.Export("考场签名单", ".xlsx", plan.Name));
     }
 
     // ═══════════════════════════════════════════
@@ -1227,7 +1228,7 @@ public sealed class ExamsController(
         return File(
             job.FileBytes,
             ExcelWorkbookHelper.ContentType,
-            job.FileName ?? "考场签名单.xlsx");
+            job.FileName ?? DownloadFileName.Export("考场签名单", ".xlsx"));
     }
 
     // ═══════════════════════════════════════════
diff --git a/src/Jiaowu.Api/Controllers/ExperimentGradesController.cs b/src/Jiaowu.Api/Controllers/ExperimentGradesController.cs
index 55a0d02..4f4f2fd 100644
--- a/src/Jiaowu.Api/Controllers/ExperimentGradesController.cs
+++ b/src/Jiaowu.Api/Controllers/ExperimentGradesController.cs
@@ -5,6 +5,7 @@ using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Grades;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Jiaowu.Api.Infrastructure.Teaching;
@@ -725,7 +726,7 @@ public sealed class ExperimentGradesController(
                 }
             });
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"实验成绩导入模板-{sheet.ExperimentProject!.Code}.xlsx");
+            DownloadFileName.Template("实验成绩", ".xlsx", sheet.ExperimentProject!.Code));
     }
 
     [HttpPost("sheets/{id:guid}/import")]
diff --git a/src/Jiaowu.Api/Controllers/GradeAnalyticsController.cs b/src/Jiaowu.Api/Controllers/GradeAnalyticsController.cs
index 7d441bd..a22d5c8 100644
--- a/src/Jiaowu.Api/Controllers/GradeAnalyticsController.cs
+++ b/src/Jiaowu.Api/Controllers/GradeAnalyticsController.cs
@@ -4,6 +4,7 @@ using Jiaowu.Api.Domain.System;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Grades;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -227,7 +228,7 @@ public sealed class GradeAnalyticsController(
             });
 
         var content = GradeAnalysisWordReportGenerator.Generate(report, DateTime.Now);
-        var fileName = $"{SanitizeFileName(report.CourseCode)}-{SanitizeFileName(report.TaskNumber)}-成绩分析报告.docx";
+        var fileName = DownloadFileName.Export("成绩分析报告", ".docx", report.CourseCode, report.TaskNumber);
         return File(
             content,
             "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
diff --git a/src/Jiaowu.Api/Controllers/GradesController.cs b/src/Jiaowu.Api/Controllers/GradesController.cs
index abdddc5..0db7050 100644
--- a/src/Jiaowu.Api/Controllers/GradesController.cs
+++ b/src/Jiaowu.Api/Controllers/GradesController.cs
@@ -7,6 +7,7 @@ using Jiaowu.Api.Domain.System;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Grades;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Jiaowu.Api.Infrastructure.Teaching;
@@ -815,7 +816,7 @@ public sealed class GradesController(
             });
         var taskName = sheet.TeachingTask!.Name;
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"成绩导入模板-{taskName}.xlsx");
+            DownloadFileName.Template("成绩", ".xlsx", taskName));
     }
 
     [HttpPost("sheets/{id:guid}/import")]
diff --git a/src/Jiaowu.Api/Controllers/OfficialDocumentsController.cs b/src/Jiaowu.Api/Controllers/OfficialDocumentsController.cs
index 4e9e26c..a00146e 100644
--- a/src/Jiaowu.Api/Controllers/OfficialDocumentsController.cs
+++ b/src/Jiaowu.Api/Controllers/OfficialDocumentsController.cs
@@ -4,6 +4,7 @@ using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.OfficialDocuments;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -220,7 +221,8 @@ public sealed class OfficialDocumentsController(
             UserAgent = Request.Headers.UserAgent.ToString()
         });
         await db.SaveChangesAsync(cancellationToken);
-        return File(document.PdfContent, "application/pdf", $"{document.DocumentNumber}.pdf");
+        return File(document.PdfContent, "application/pdf",
+            DownloadFileName.Document("公文", ".pdf", document.DocumentNumber));
     }
 
     [HttpGet("{id:guid}/downloads")]
diff --git a/src/Jiaowu.Api/Controllers/OtherExamsController.cs b/src/Jiaowu.Api/Controllers/OtherExamsController.cs
index 21eac15..a549d2f 100644
--- a/src/Jiaowu.Api/Controllers/OtherExamsController.cs
+++ b/src/Jiaowu.Api/Controllers/OtherExamsController.cs
@@ -5,6 +5,7 @@ using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -114,7 +115,8 @@ public sealed class OtherExamsController(AppDbContext db, ICurrentUserDataScope
         if (batch is null) return NotFound();
         var headers = HeadersFor(batch);
         var bytes = ExcelWorkbookHelper.Create("其他考试成绩导入", headers, [], ["第一行为表头，请勿修改；每行填写一名学生。", "学号用于自动匹配姓名、学院和班级，参加次数由系统自动计算。"]);
-        return File(bytes, ExcelWorkbookHelper.ContentType, $"其他考试成绩导入模板-{batch.ExamCode ?? batch.Name}.xlsx");
+        return File(bytes, ExcelWorkbookHelper.ContentType,
+            DownloadFileName.Template("其他考试成绩", ".xlsx", batch.ExamCode ?? batch.Name));
     }
 
     [HttpPost("batches/{id:guid}/import")]
diff --git a/src/Jiaowu.Api/Controllers/PersonnelExcelController.cs b/src/Jiaowu.Api/Controllers/PersonnelExcelController.cs
index 026522b..ebcbee5 100644
--- a/src/Jiaowu.Api/Controllers/PersonnelExcelController.cs
+++ b/src/Jiaowu.Api/Controllers/PersonnelExcelController.cs
@@ -4,6 +4,7 @@ using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Academic;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -74,7 +75,7 @@ public sealed class PersonnelExcelController(
                 "整批数据会先校验，任一行有误时均不会写入。"
             ]);
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"{RegistryName(kind)}导入模板.xlsx");
+            DownloadFileName.Template(RegistryName(kind), ".xlsx"));
     }
 
     [HttpGet("{kind}/export")]
@@ -120,7 +121,7 @@ public sealed class PersonnelExcelController(
 
         var bytes = ExcelWorkbookHelper.Create(RegistryName(kind), headers, rows);
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"{RegistryName(kind)}-{DateTime.Now:yyyyMMdd-HHmm}.xlsx");
+            DownloadFileName.Export(RegistryName(kind), ".xlsx"));
     }
 
     [HttpGet("students/current-courses/export")]
@@ -174,7 +175,7 @@ public sealed class PersonnelExcelController(
             StudentCurrentCourseHeaders,
             rows);
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"学生正在修读课程-{DateTime.Now:yyyyMMdd-HHmm}.xlsx");
+            DownloadFileName.Export("学生正在修读课程", ".xlsx"));
     }
 
     [HttpPost("{kind}/import")]
diff --git a/src/Jiaowu.Api/Controllers/StatisticsController.cs b/src/Jiaowu.Api/Controllers/StatisticsController.cs
index d63fbd0..55dd2fc 100644
--- a/src/Jiaowu.Api/Controllers/StatisticsController.cs
+++ b/src/Jiaowu.Api/Controllers/StatisticsController.cs
@@ -4,6 +4,7 @@ using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -1047,7 +1048,7 @@ public sealed class StatisticsController(
         workbook.SaveAs(stream);
         return File(stream.ToArray(),
             "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
-            $"{title}.xlsx");
+            DownloadFileName.Export(title, ".xlsx"));
     }
 
     private static string MapCourseNature(CourseNature nature) => nature switch
diff --git a/src/Jiaowu.Api/Controllers/TimetableManagementController.cs b/src/Jiaowu.Api/Controllers/TimetableManagementController.cs
index 5784bf1..a454452 100644
--- a/src/Jiaowu.Api/Controllers/TimetableManagementController.cs
+++ b/src/Jiaowu.Api/Controllers/TimetableManagementController.cs
@@ -3,6 +3,7 @@ using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Jiaowu.Api.Infrastructure.OfficialDocuments;
 using Jiaowu.Api.Infrastructure.Timetables;
@@ -168,8 +169,7 @@ public sealed class TimetableManagementController(
             cancellationToken);
         if (result.Result is null) return result.Error!;
         var bytes = TimetableExcelExporter.Create(result.Result);
-        var fileName =
-            $"{FileName(result.Result.Subject.Name)}-{FileName(result.Result.Term.Name)}-课表.xlsx";
+        var fileName = DownloadFileName.Export("课表", ".xlsx", result.Result.Subject.Name, result.Result.Term.Name);
         return File(bytes, ExcelWorkbookHelper.ContentType, fileName);
     }
 
@@ -196,7 +196,7 @@ public sealed class TimetableManagementController(
         }
 
         var bytes = TimetableExcelExporter.Create(timetables);
-        var fileName = $"课表批量导出-{FileName(timetables[0].Term.Name)}.xlsx";
+        var fileName = DownloadFileName.Export("课表批量导出", ".xlsx", timetables[0].Term.Name);
         return File(bytes, ExcelWorkbookHelper.ContentType, fileName);
     }
 
@@ -240,7 +240,7 @@ public sealed class TimetableManagementController(
             timetables.Add(result.Result);
         }
 
-        var fileName = $"课表批量导出-{FileName(timetables[0].Term.Name)}.pdf";
+        var fileName = DownloadFileName.Export("课表批量导出", ".pdf", timetables[0].Term.Name);
         return File(TimetablePdfExporter.Create(timetables, officialDocumentOptions.FontPath), "application/pdf", fileName);
     }
 
@@ -259,7 +259,7 @@ public sealed class TimetableManagementController(
             .Select(x => new object?[] { "教学楼空余教室", x.Name, "/venue-display/building/" + x.Id })
             .ToListAsync(cancellationToken);
         var bytes = ExcelWorkbookHelper.Create("展牌链接", ["展牌类型", "场地", "相对链接"], classrooms.Concat(buildings).ToList());
-        return File(bytes, ExcelWorkbookHelper.ContentType, "场地信息展牌链接.xlsx");
+        return File(bytes, ExcelWorkbookHelper.ContentType, DownloadFileName.Export("场地信息展牌链接", ".xlsx"));
     }
 
     private async Task<(TimetableData? Result, ActionResult? Error)> LoadAuthorizedAsync(
@@ -301,7 +301,7 @@ public sealed class TimetableManagementController(
         File(
             TimetablePdfExporter.Create(timetable, officialDocumentOptions.FontPath),
             "application/pdf",
-            $"{FileName(timetable.Subject.Name)}-{FileName(timetable.Term.Name)}-课表.pdf");
+            DownloadFileName.Export("课表", ".pdf", timetable.Subject.Name, timetable.Term.Name));
 }
 
 public sealed record TimetableBatchExportRequest(
diff --git a/src/Jiaowu.Api/Controllers/TimetablesController.cs b/src/Jiaowu.Api/Controllers/TimetablesController.cs
index bc0e256..9793514 100644
--- a/src/Jiaowu.Api/Controllers/TimetablesController.cs
+++ b/src/Jiaowu.Api/Controllers/TimetablesController.cs
@@ -4,6 +4,7 @@ using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Jiaowu.Api.Infrastructure.OfficialDocuments;
 using Jiaowu.Api.Infrastructure.Timetables;
@@ -356,7 +357,7 @@ public sealed class TimetablesController(
         return File(
             result.Content,
             "text/calendar; charset=utf-8",
-            $"{SafeFileName(user.DisplayName)}-个人教学日历.ics");
+            DownloadFileName.Export("个人教学日历", ".ics", user.DisplayName));
     }
 
     [HttpGet("calendar/{userId:guid}/{accessToken}.ics")]
@@ -510,15 +511,13 @@ public sealed class TimetablesController(
     private ActionResult ExcelFile(TimetableData result)
     {
         var bytes = TimetableExcelExporter.Create(result);
-        var fileName =
-            $"{SafeFileName(result.Subject.Name)}-{SafeFileName(result.Term.Name)}-课表.xlsx";
+        var fileName = DownloadFileName.Export("课表", ".xlsx", result.Subject.Name, result.Term.Name);
         return File(bytes, ExcelWorkbookHelper.ContentType, fileName);
     }
 
     private ActionResult PdfFile(TimetableData result)
     {
-        var fileName =
-            $"{SafeFileName(result.Subject.Name)}-{SafeFileName(result.Term.Name)}-课表.pdf";
+        var fileName = DownloadFileName.Export("课表", ".pdf", result.Subject.Name, result.Term.Name);
         return File(TimetablePdfExporter.Create(result, officialDocumentOptions.FontPath), "application/pdf", fileName);
     }
 
diff --git a/src/Jiaowu.Api/Controllers/UsersExcelController.cs b/src/Jiaowu.Api/Controllers/UsersExcelController.cs
index c8f401b..7a64404 100644
--- a/src/Jiaowu.Api/Controllers/UsersExcelController.cs
+++ b/src/Jiaowu.Api/Controllers/UsersExcelController.cs
@@ -2,6 +2,7 @@ using System.Security.Claims;
 using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Excel;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Identity;
@@ -36,7 +37,7 @@ public sealed class UsersExcelController(
                 "教师或学生角色必须填写已存在且未关联其他账号的工号/学号。",
                 "状态填写“启用”或“停用”；整批校验失败时不会写入。"
             ]);
-        return File(bytes, ExcelWorkbookHelper.ContentType, "用户与权限导入模板.xlsx");
+        return File(bytes, ExcelWorkbookHelper.ContentType, DownloadFileName.Template("用户与权限", ".xlsx"));
     }
 
     [HttpGet("export")]
@@ -63,7 +64,7 @@ public sealed class UsersExcelController(
         }
         var bytes = ExcelWorkbookHelper.Create("用户与权限", Headers, rows);
         return File(bytes, ExcelWorkbookHelper.ContentType,
-            $"用户与权限-{DateTime.Now:yyyyMMdd-HHmm}.xlsx");
+            DownloadFileName.Export("用户与权限", ".xlsx"));
     }
 
     [HttpPost("import")]
diff --git a/src/Jiaowu.Api/Infrastructure/Exams/ExamSignInExportJobProcessor.cs b/src/Jiaowu.Api/Infrastructure/Exams/ExamSignInExportJobProcessor.cs
index 1462b0d..fedbfc9 100644
--- a/src/Jiaowu.Api/Infrastructure/Exams/ExamSignInExportJobProcessor.cs
+++ b/src/Jiaowu.Api/Infrastructure/Exams/ExamSignInExportJobProcessor.cs
@@ -1,5 +1,6 @@
 using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Infrastructure.Persistence;
+using Jiaowu.Api.Infrastructure.Files;
 using Jiaowu.Api.Infrastructure.Teaching;
 using Microsoft.EntityFrameworkCore;
 
@@ -158,7 +159,7 @@ public sealed class ExamSignInExportJobProcessor(
             var bytes = ExamSignInWorkbookExporter.Create(data);
 
             job.Status = ExamSignInExportJobStatus.Succeeded;
-            job.FileName = $"考场签名单-{SanitizeFileName(plan.Name)}.xlsx";
+            job.FileName = DownloadFileName.Export("考场签名单", ".xlsx", plan.Name);
             job.FileBytes = bytes;
             job.FileSize = bytes.Length;
             job.CurrentStep = "生成完成";
diff --git a/src/Jiaowu.Api/Infrastructure/Files/DownloadFileName.cs b/src/Jiaowu.Api/Infrastructure/Files/DownloadFileName.cs
new file mode 100644
index 0000000..ff65cf7
--- /dev/null
+++ b/src/Jiaowu.Api/Infrastructure/Files/DownloadFileName.cs
@@ -0,0 +1,44 @@
+namespace Jiaowu.Api.Infrastructure.Files;
+
+/// <summary>
+/// Creates predictable, Windows-safe names for files the browser downloads.
+/// </summary>
+public static class DownloadFileName
+{
+    public static string Export(string title, string extension, params string?[] parts) =>
+        Build(title, extension, includeTimestamp: true, parts);
+
+    public static string Template(string title, string extension, params string?[] parts) =>
+        Build(title, extension, includeTimestamp: false, [.. parts, "导入模板"]);
+
+    public static string Document(string title, string extension, params string?[] parts) =>
+        Build(title, extension, includeTimestamp: false, parts);
+
+    private static string Build(
+        string title,
+        string extension,
+        bool includeTimestamp,
+        IReadOnlyCollection<string?> parts)
+    {
+        var segments = new List<string> { Clean(title) };
+        segments.AddRange(parts.Select(Clean).Where(value => value.Length > 0));
+        if (includeTimestamp)
+            segments.Add(DateTime.Now.ToString("yyyyMMdd-HHmmss"));
+
+        var name = string.Join('-', segments.Where(value => value.Length > 0));
+        if (name.Length > 180) name = name[..180].TrimEnd('.', ' ');
+        return $"{name}{NormalizeExtension(extension)}";
+    }
+
+    private static string Clean(string? value)
+    {
+        if (string.IsNullOrWhiteSpace(value)) return string.Empty;
+        var invalid = Path.GetInvalidFileNameChars();
+        var cleaned = new string(value.Trim().Select(character =>
+            invalid.Contains(character) ? '-' : character).ToArray());
+        return cleaned.Trim('.', ' ');
+    }
+
+    private static string NormalizeExtension(string extension) =>
+        extension.StartsWith('.') ? extension : $".{extension}";
+}
diff --git a/tests/Jiaowu.Api.Tests/DownloadFileNameTests.cs b/tests/Jiaowu.Api.Tests/DownloadFileNameTests.cs
new file mode 100644
index 0000000..2c5a495
--- /dev/null
+++ b/tests/Jiaowu.Api.Tests/DownloadFileNameTests.cs
@@ -0,0 +1,20 @@
+using Jiaowu.Api.Infrastructure.Files;
+
+namespace Jiaowu.Api.Tests;
+
+public sealed class DownloadFileNameTests
+{
+    [Fact]
+    public void Export_includes_safe_context_and_a_second_precision_timestamp()
+    {
+        var name = DownloadFileName.Export("课程/名单", "xlsx", " A:B ");
+
+        Assert.Matches("^课程-名单-A-B-\\d{8}-\\d{6}\\.xlsx$", name);
+    }
+
+    [Fact]
+    public void Template_has_a_stable_descriptive_name()
+    {
+        Assert.Equal("课程库-导入模板.xlsx", DownloadFileName.Template("课程库", ".xlsx"));
+    }
+}
diff --git a/web/src/views/OtherExamsView.vue b/web/src/views/OtherExamsView.vue
index d92e2e4..1025af6 100644
--- a/web/src/views/OtherExamsView.vue
+++ b/web/src/views/OtherExamsView.vue
@@ -3,6 +3,7 @@ import { computed, onMounted, reactive, ref } from 'vue'
 import { ElMessage } from 'element-plus'
 import { Download, Plus, Promotion, Refresh, Search, Upload } from '@element-plus/icons-vue'
 import http, { apiErrorMessage } from '../api/http'
+import { downloadApiFile } from '../api/excel'
 import { useAuthStore } from '../stores/auth'
 
 type ResultRow = { studentNumber: string; studentName?: string; collegeName?: string; className?: string; attemptNumber?: number; score: number | null; level: string; isPassed: boolean | null; notes: string }
@@ -97,8 +98,7 @@ async function createBatch() {
 }
 async function downloadTemplate() {
   try {
-    const response = await http.get(`/other-exams/batches/${selected.value.id}/template`, { responseType: 'blob' })
-    const url = URL.createObjectURL(response.data); const link = document.createElement('a'); link.href = url; link.download = `其他考试成绩导入模板-${selected.value.examCode || selected.value.name}.xlsx`; link.click(); URL.revokeObjectURL(url)
+    await downloadApiFile(`/other-exams/batches/${selected.value.id}/template`, '其他考试成绩-导入模板.xlsx')
   } catch (error) { ElMessage.error(apiErrorMessage(error)) }
 }
 async function importExcel(event: Event) {