WinCE File Timestamp Tool

Modify file creation, last write, and last access timestamps on Windows CE / Windows Mobile devices running .NET Compact Framework 3.5. A touch-equivalent for embedded Windows. GUI + CLI.

A small, dependency-free C# tool to change file timestamps on Windows CE devices. Originally built for industrial PM2.5 monitoring devices (CEP series), but works on any Windows CE 5.x / 6.x / Windows Mobile 5/6 device with .NET Compact Framework 3.5.

Why

Windows CE / Windows Mobile devices rarely ship with a touch-equivalent utility, and the .NET Compact Framework File API does not reliably expose SetCreationTime / SetLastAccessTime (only SetLastWriteTime is consistent).

This tool calls the underlying Win32 API SetFileTime via P/Invoke into coredll.dll (CE) or kernel32.dll (desktop test build), which lets you set all three timestamps independently and reliably.

Use cases:

• Industrial PDAs / HMIs / Pocket PCs — fix data file timestamps after a clock issue
• Battery-died devices — restore correct timestamps after RTC reset
• Pre-production normalization — set deterministic timestamps on golden images
• Air quality / environmental monitors — correct device-side data file metadata
• Forensic / archival — controlled backdating in audited workflows

Features

• ✅ Modify creation / last write / last access independently (each can be skipped)
• ✅ GUI mode — double-click on the device, no command line needed
• ✅ Batch mode — Base64-encoded config, deployable via SD card / FTP / over-the-air
• ✅ Tolerant Chinese-friendly date parsing — 2025-01-15 10:30, 2025年1月15日, 2025/1/15, etc.
• ✅ Wildcard expansion — *.dat, **/*.txt recursive globs
• ✅ Dry-run preview in batch mode
• ✅ Single 32 KB exe, no installer, no runtime download (CF 3.5 is shipped on most CE images)
• ✅ Dual build — CE binary for production, desktop test binary for verifying logic on Win10

Quick Start

1. Build

On a Windows machine with .NET Framework 3.5 enabled and the .NET Compact Framework 3.5 reference assemblies available (typically from a Visual Studio 2008 Pro install — see docs/BUILD_GUIDE.md):

build_settime_ce.bat

Output: SetTime.exe (~32 KB).

2. Deploy

Copy SetTime.exe to the device (e.g. \Storage Card\SetTime\ or \硬盘\SetTime\).

3. Use

GUI mode (recommended for end-users):

Double-click SetTime.exe on the device. A window appears with:

• Directory picker (Browse button uses OpenFileDialog)
• Filename filter (e.g. *.dat)
• "Include subdirectories" checkbox
• Target time input (accepts many formats)
• Three checkboxes: ☑ Creation / ☑ Last Write / ☑ Last Access
• Confirm dialog before applying

Batch mode (for automation):

Provide a Base64-encoded config:

settime
\Storage Card\data\sample.txt,2025-01-15 10:30:00
\Storage Card\data\*.dat,2025-03-01 08:00:00,+30s

Encode it (PowerShell):

[Convert]::ToBase64String([Text.Encoding]::UTF8.GetBytes((Get-Content .\config.txt -Raw))) | Set-Content .\settime.ini -Encoding ASCII

Then run:

SetTime.exe settime.ini
SetTime.exe settime.ini --dry-run    # preview without modifying

See settime_sample.txt for a working example.

Date Format Support (GUI Mode)

The GUI input accepts (case-insensitive, whitespace-tolerant):

2025-01-15 10:30:00
2025-01-15 10:30
2025-1-15 10:30
2025/01/15 10:30:00
2025/1/15
2025-01-15
2025年1月15日 10:30
2025年1月15日
2025年1月15日 10点30分

If only a date is given, time defaults to 00:00:00.

Builds

Build	Output	Target	Use
build_settime_ce.bat	SetTime.exe	.NET CF 3.5	Production — deploy to CE devices
build_settime_win10.bat	SetTime_Desktop.exe	.NET Framework 3.5 desktop	Development verification on Windows 10

Both are produced from the same SetTime.cs via the WIN10_DESKTOP preprocessor symbol, which switches:

• P/Invoke target: coredll.dll (CE) ↔ kernel32.dll (desktop)
• [STAThread] attribute on Main (required for desktop MessageBox, absent on CF)
• Assembly path resolution: Assembly.Location (desktop) ↔ GetName().CodeBase (CF)

How It Works

P/Invoke chain in SetTime.cs:

[DllImport("coredll.dll", EntryPoint = "CreateFileW", ...)]   // CE
// or "kernel32.dll" on desktop
private static extern IntPtr CreateFile(string fileName, uint access, ...);

[DllImport("coredll.dll", EntryPoint = "SetFileTime", ...)]
private static extern bool SetFileTime(
    IntPtr hFile,
    IntPtr lpCreationTime,    // IntPtr.Zero to skip
    IntPtr lpLastAccessTime,
    IntPtr lpLastWriteTime);

[DllImport("coredll.dll", EntryPoint = "CloseHandle", ...)]
private static extern bool CloseHandle(IntPtr handle);

Each timestamp pointer is allocated via Marshal.AllocHGlobal only when that checkbox is ticked, allowing independent modification of any subset of the three timestamps. IntPtr.Zero tells the Win32 API to leave that field unchanged.

Read-only / hidden / system attributes are temporarily cleared before SetFileTime and restored after, so protected files can be modified without permanently changing their attributes.

CF 3.5 API Quirks Handled

If you're targeting CF 3.5 yourself, watch out for these (all addressed in this code):

Desktop API	CF 3.5 alternative
[STAThread] on Main	Not supported; use plain Main
File.GetAttributes / File.SetAttributes	Use FileInfo.Attributes instead
Application.ExecutablePath	Use Assembly.GetExecutingAssembly().GetName().CodeBase
Control.SetBounds(x, y, w, h)	Use Location = new Point(...) and Size = new Size(...)
MessageBox.Show(text, caption, buttons) (3-arg)	Must include MessageBoxIcon and MessageBoxDefaultButton
DateTime.TryParseExact	Use ParseExact wrapped in try/catch (FormatException)
Directory.GetFiles(path, pattern, AllDirectories)	Manually recurse with Directory.GetDirectories
File.ReadAllBytes	Use FileStream.Read loop
Generic List<T>	Use ArrayList for portability across CF revisions

Documentation

• BUILD_GUIDE.md — extracting CF 3.5 reference assemblies from a VS2008 ISO without a full install
• VERIFICATION.md — three-tier verification approach (static / desktop emulator / device)

Limitations

• No multi-file picker in GUI mode — pick a directory + filter, or pick one file via OpenFileDialog. Multi-select on CF 3.5 OpenFileDialog is unreliable across CE images.
• No relative date support — today, now, etc. are not parsed (deliberately, to avoid timezone surprises).
• Time zone: timestamps are interpreted in the device's local time. Verify the device clock displays the expected time before running.
• CE x86 target only — recompile for ARM if needed (csc with /platform:ARM is not available; use corflags or rebuild with appropriate flags).

Contributing

Issues and PRs welcome. Common asks:

• ARM build instructions
• Native C++ port (for CE images without .NET CF)
• More date formats (e.g. ISO 8601 with timezone)
• Localization beyond Chinese / English

License

MIT — see LICENSE.

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中文简介

WinCE 文件时间戳修改工具——给跑 .NET Compact Framework 3.5 的 Windows CE / Windows Mobile 设备改文件的创建时间、修改时间、访问时间。最初为工业 PM2.5 监测设备开发，适用于任何带 CF 3.5 的 PocketPC / WM5 / WM6 / WinCE 5.x / WinCE 6.x 设备。

功能：

• 三个时间戳分别勾选（任选其一或全选）
• GUI 模式：设备上双击，零命令行
• 批处理模式：base64 编码配置，可走 SD 卡 / FTP / 远程下发
• 中文友好的日期解析（年月日点分秒，全角冒号都吃）
• 通配符 * **，支持递归
• 32 KB 单文件 exe，无依赖

构建：

需要 Windows 上的 .NET Framework 3.5 + .NET CF 3.5 引用程序集（VS2008 Pro ISO 里有）。详见 docs/BUILD_GUIDE.md。

部署：把 SetTime.exe 拷到设备（如 \硬盘\SetTime\）双击运行。

许可证：MIT