# DelExcept - Selective File Deletion Script

A Windows batch script (`delexcept.cmd`) that deletes all files in a directory and its subdirectories while preserving files that match specified patterns.

## Features

- ✅ **Recursive deletion** - Processes all subdirectories
- ✅ **Pattern matching** - Supports wildcards (`*` and `?`)
- ✅ **Safety confirmation** - Prompts before execution
- ✅ **Flexible arguments** - Command line configurable
- ✅ **Error handling** - Handles access errors gracefully
- ✅ **Progress feedback** - Shows which files are kept/deleted

## Usage

```cmd
delexcept.cmd [TARGET_DIR] [KEEP_FILES]
```

### Arguments

| Argument | Description | Default |
|----------|-------------|---------|
| `TARGET_DIR` | Directory to process | Current directory (`%CD%`) |
| `KEEP_FILES` | Space-separated patterns of files to preserve | `*.log *.cfg` |

### Examples

#### Basic Usage
```cmd
# Delete all files in current directory except *.log and *.cfg
delexcept.cmd

# Process specific directory with default keep patterns
delexcept.cmd "C:\MyFolder"

# Keep only text files in specified directory
delexcept.cmd "C:\Temp" "*.txt"
```

#### Advanced Pattern Matching
```cmd
# Keep multiple file types
delexcept.cmd "D:\Project" "*.log *.cfg *.ini *.txt"

# Mix wildcards with exact filenames
delexcept.cmd "." "important.sql backup.* *.log"

# Use single character wildcards
delexcept.cmd "C:\Data" "config.? log*.txt"
```

## Wildcard Patterns

| Pattern | Description | Example Matches |
|---------|-------------|-----------------|
| `*` | Any number of characters | `*.txt` → `file.txt`, `document.txt` |
| `?` | Single character | `log?.txt` → `log1.txt`, `logA.txt` |
| `*.*` | Any file with extension | All files with extensions |
| `file.*` | Specific name, any extension | `file.txt`, `file.log`, `file.cfg` |

## Safety Features

### Confirmation Prompt
The script displays a warning and requires user confirmation:
```
WARNING: This will delete all files in "C:\MyFolder" and subdirectories
EXCEPT files matching these patterns: *.log *.cfg

Are you sure? (Y/N):
```

### Error Handling
- Validates directory access before processing
- Reports files that cannot be deleted
- Graceful handling of permission errors

## Getting Help

Display usage information:
```cmd
delexcept.cmd -h
delexcept.cmd --help
delexcept.cmd /?
```

## Installation

1. Save the script as `delexcept.cmd`
2. Place it in a directory in your PATH, or
3. Run it from its location using full path

## Common Use Cases

### Development Environment Cleanup
```cmd
# Keep source code, remove build artifacts
delexcept.cmd "C:\MyProject" "*.cs *.sql *.js *.html *.css"
```

### Log Directory Maintenance
```cmd
# Keep recent logs, remove everything else
delexcept.cmd "C:\Logs" "*.log *.txt"
```

### Backup Directory Cleanup
```cmd
# Keep specific backup files
delexcept.cmd "D:\Backups" "backup_*.sql important.*"
```

### Temporary File Cleanup
```cmd
# Remove temp files but keep configuration
delexcept.cmd "%TEMP%" "*.cfg *.ini *.conf"
```

## Important Notes

⚠️ **Warning**: This script permanently deletes files. Always test with a backup or in a safe environment first.

### Best Practices

1. **Test first**: Run the script in a test directory to verify pattern matching
2. **Use quotes**: Always quote paths with spaces: `"C:\My Folder"`
3. **Check patterns**: Verify your wildcard patterns match the intended files
4. **Backup important data**: Always maintain backups of critical files

### Limitations

- Case-insensitive pattern matching only
- No regular expression support (only `*` and `?` wildcards)
- Requires manual confirmation for each execution
- Windows-only (batch script)

## Troubleshooting

### Common Issues

**"Cannot access directory" error**
- Verify the directory path exists
- Check permissions for the target directory
- Ensure no other processes are using files in the directory

**Files not matching expected patterns**
- Test patterns with `dir` command first: `dir *.log`
- Remember patterns are case-insensitive
- Use quotes around patterns with special characters

**Permission denied errors**
- Run as administrator if needed
- Close applications that might be using the files
- Check file attributes (read-only, hidden)

### Testing Patterns

Before running the deletion script, test your patterns:
```cmd
# Test what files match your pattern
dir /s "*.log"
dir /s "config.*"
```

## Version History

- **v1.0**: Initial release with basic functionality
- **v1.1**: Added command line arguments and wildcard support
- **v1.2**: Enhanced pattern matching and error handling

## License

This script is provided as-is for educational and practical use. Use at your own risk.