A simple 🎯 C# Windows Forms application that allows users to batch rename multiple files 📁 using custom names entered in a textbox. The app also supports adding 🔤 prefixes and suffixes, as well as automatic numbering or lettering.
✅ Select multiple files using a file picker
🧩 View original filenames (name + extension) in a clean, numbered list
📝 Enter new names (one per line) in a textbox
🧷 Add prefix and/or suffix to new filenames
🔢 Enable Auto Numbering (1, 2, 3...) or Auto Lettering (A, B, C...) as suffix
👀 Preview renaming result before applying
📌 Rename files while preserving their original extensions
🛡️ Error handling for:
- 🔢 Name count mismatch
- 🚫 Invalid or forbidden characters
⚠️ File system errors (e.g., permission denied)
📂 Open Files: Select multiple files from your system
🖊️ New Names Textbox: Type the new names, each on a separate line
🔠 Prefix/Suffix Inputs: Optional text to add before/after names
🔢 Auto Suffix Options:
- Auto Numbering →
filename1.ext,filename2.ext - Auto Lettering →
filenameA.ext,filenameB.ext
🔍 Preview: Shows a list likeoldname.ext → newname.ext
📁 Change File Names: Renames all selected files
- 📥 Clone the repository or download the
.exe ▶️ Run the application- 📑 Click Open Files and select files
- ✏️ Enter new names (one per line) — same count as files
- 🔧 (Optional) Add prefix, suffix, or enable auto numbering/lettering
- ✅ Click Change File Names to apply changes
- 🧠 Language: C#
- 💻 Framework: .NET Framework (Windows Forms)
🚫 Invalid characters like \ / : * ? " < > | are not allowed
📛 Files will not be overwritten if a duplicate name exists
👁️ Always use Preview to confirm the rename operation
📄 MIT License – Free to use, modify, and share.