ASP FileSystem
FileSystemObject 的文件、文件夹、驱动器、文本流操作。
Key PointsFileSystemObject 是操作磁盘的入口：它能建删文件目录、读写文本、遍历磁盘。
创建与常用方法
ASP
<%
Dim fso
Set fso = Server.CreateObject("Scripting.FileSystemObject")
' 判断存在
Response.Write fso.FileExists(Server.MapPath("/data/a.txt")) & "<br>"
Response.Write fso.FolderExists(Server.MapPath("/data")) & "<br>"
' 创建文件夹
If Not fso.FolderExists(Server.MapPath("/logs")) Then
fso.CreateFolder Server.MapPath("/logs")
End If
' 复制 / 移动 / 删除
fso.CopyFile Server.MapPath("/data/a.txt"), Server.MapPath("/data/b.txt")
fso.MoveFile Server.MapPath("/data/b.txt"), Server.MapPath("/backup/b.txt")
fso.DeleteFile Server.MapPath("/data/a.txt"), True ' True = 只读也删
Set fso = Nothing
%>取文件信息
ASP
<%
Dim f
Set f = fso.GetFile(Server.MapPath("/data/report.pdf"))
Response.Write "名称：" & f.Name & "<br>"
Response.Write "大小：" & f.Size & " 字节<br>"
Response.Write "创建：" & f.DateCreated & "<br>"
Response.Write "修改：" & f.DateLastModified & "<br>"
Response.Write "类型：" & f.Type & "<br>"
Response.Write "父目录：" & f.ParentFolder.Path
%>Output
名称：report.pdf
大小：184320 字节
创建：2026/10/1 9:12:03
修改：2026/11/2 17:40:55
类型：PDF 文档
父目录：C:\inetpub\wwwroot\data遍历目录
ASP
<%
Dim folder, file, sub_
Set folder = fso.GetFolder(Server.MapPath("/data"))
Response.Write "<h3>文件</h3>"
For Each file In folder.Files
Response.Write file.Name & " — " & file.Size & " 字节<br>"
Next
Response.Write "<h3>子目录</h3>"
For Each sub_ In folder.SubFolders
Response.Write sub_.Name & "<br>"
Next
%>Output
文件
report.pdf — 184320 字节
notes.txt — 1024 字节
子目录
archive
temp读写文本
ASP
<%
Dim ts
' 写（覆盖）
Set ts = fso.CreateTextFile(Server.MapPath("/logs/app.log"), True)
ts.WriteLine Now() & " 启动"
ts.Close
' 追加
Set ts = fso.OpenTextFile(Server.MapPath("/logs/app.log"), 8, True)
ts.WriteLine Now() & " 追加一行"
ts.Close
' 读全部
Set ts = fso.OpenTextFile(Server.MapPath("/logs/app.log"), 1)
Response.Write ts.ReadAll
ts.Close
Set ts = Nothing
%>Output
2026/11/3 14:20:01 启动
2026/11/3 14:25:09 追加一行| Mode | Constant | Meaning |
|---|---|---|
| Read | 1 | ForReading |
| Write | 2 | ForWriting，覆盖原内容 |
| Append | 8 | ForAppending，写到末尾 |
路径拼接
ASP
<%
Dim p
p = fso.BuildPath(Server.MapPath("/logs"), "2026-11-03.log")
Response.Write p & "<br>"
Response.Write fso.GetParentFolderName(p) & "<br>"
Response.Write fso.GetBaseName(p) & "<br>"
Response.Write fso.GetExtensionName(p)
%>Output
C:\inetpub\wwwroot\logs\2026-11-03.log
C:\inetpub\wwwroot\logs
2026-11-03
logUse BuildPath instead of concatenating "\": it handles duplicated or missing separators. Hand-building gives \\ when the base already ends in a backslash — Windows usually tolerates it, but it is sloppy.
Never build file paths straight from
Request. fso.DeleteFile Server.MapPath(Request("f")) lets an attacker delete system files with ../../windows/system32/x.dll. Whitelist or constrain paths to a fixed directory with BuildPath.权限问题
Text
IIS 以 IUSR（或应用池标识）运行，默认只有读权限。
要写文件，必须给目标目录加写权限：
右键目录 → 属性 → 安全 → 编辑 → 添加 IUSR → 勾选「修改」Without write permission you get Permission denied (error 70). Granting Everyone full control is the wrong reflex; give only IUSR or the app-pool identity the minimum it needs.
创建与常用方法
ASP
<%
Dim fso
Set fso = Server.CreateObject("Scripting.FileSystemObject")
' 判断存在
Response.Write fso.FileExists(Server.MapPath("/data/a.txt")) & "<br>"
Response.Write fso.FolderExists(Server.MapPath("/data")) & "<br>"
' 创建文件夹
If Not fso.FolderExists(Server.MapPath("/logs")) Then
fso.CreateFolder Server.MapPath("/logs")
End If
' 复制 / 移动 / 删除
fso.CopyFile Server.MapPath("/data/a.txt"), Server.MapPath("/data/b.txt")
fso.MoveFile Server.MapPath("/data/b.txt"), Server.MapPath("/backup/b.txt")
fso.DeleteFile Server.MapPath("/data/a.txt"), True ' True = 只读也删
Set fso = Nothing
%>取文件信息
ASP
<%
Dim f
Set f = fso.GetFile(Server.MapPath("/data/report.pdf"))
Response.Write "名称：" & f.Name & "<br>"
Response.Write "大小：" & f.Size & " 字节<br>"
Response.Write "创建：" & f.DateCreated & "<br>"
Response.Write "修改：" & f.DateLastModified & "<br>"
Response.Write "类型：" & f.Type & "<br>"
Response.Write "父目录：" & f.ParentFolder.Path
%>Output
名称：report.pdf
大小：184320 字节
创建：2026/10/1 9:12:03
修改：2026/11/2 17:40:55
类型：PDF 文档
父目录：C:\inetpub\wwwroot\data遍历目录
ASP
<%
Dim folder, file, sub_
Set folder = fso.GetFolder(Server.MapPath("/data"))
Response.Write "<h3>文件</h3>"
For Each file In folder.Files
Response.Write file.Name & " — " & file.Size & " 字节<br>"
Next
Response.Write "<h3>子目录</h3>"
For Each sub_ In folder.SubFolders
Response.Write sub_.Name & "<br>"
Next
%>Output
文件
report.pdf — 184320 字节
notes.txt — 1024 字节
子目录
archive
temp读写文本
ASP
<%
Dim ts
' 写（覆盖）
Set ts = fso.CreateTextFile(Server.MapPath("/logs/app.log"), True)
ts.WriteLine Now() & " 启动"
ts.Close
' 追加
Set ts = fso.OpenTextFile(Server.MapPath("/logs/app.log"), 8, True)
ts.WriteLine Now() & " 追加一行"
ts.Close
' 读全部
Set ts = fso.OpenTextFile(Server.MapPath("/logs/app.log"), 1)
Response.Write ts.ReadAll
ts.Close
Set ts = Nothing
%>Output
2026/11/3 14:20:01 启动
2026/11/3 14:25:09 追加一行| 模式 | 常量 | 含义 |
|---|---|---|
| 只读 | 1 | ForReading |
| 写 | 2 | ForWriting，覆盖原内容 |
| 追加 | 8 | ForAppending，写到末尾 |
路径拼接
ASP
<%
Dim p
p = fso.BuildPath(Server.MapPath("/logs"), "2026-11-03.log")
Response.Write p & "<br>"
Response.Write fso.GetParentFolderName(p) & "<br>"
Response.Write fso.GetBaseName(p) & "<br>"
Response.Write fso.GetExtensionName(p)
%>Output
C:\inetpub\wwwroot\logs\2026-11-03.log
C:\inetpub\wwwroot\logs
2026-11-03
log用 BuildPath 而不是手拼 "\"，它会处理末尾分隔符重复或缺失的问题。手拼 path & "\" & name 在 path 已带反斜杠时会得到 \\，虽然 Windows 通常容忍，但不干净。
文件操作的路径绝不能直接来自
Request。fso.DeleteFile Server.MapPath(Request("f")) 这样的代码，传 ../../windows/system32/x.dll 就能删系统文件。路径必须白名单校验，或在固定目录内 BuildPath。权限问题
Text
IIS 以 IUSR（或应用池标识）运行，默认只有读权限。
要写文件，必须给目标目录加写权限：
右键目录 → 属性 → 安全 → 编辑 → 添加 IUSR → 勾选「修改」没有写权限时报 Permission denied（错误号 70）。很多人第一反应是「给 Everyone 完全控制」——那是把整个目录对所有人开放，正确做法是只给 IUSR 或应用池账户所需的最小权限。