Add -RenamePattern/-RenameReplacement for renaming files before upload

README.md

@@ -42,6 +42,8 @@ The script auto-searches these locations in order:
 | `-CredentialFile` | No | — | Path to saved credential XML (see below) |
 | `-KeyFilePath` | No | — | Path to SSH private key (`.ppk`) |
 | `-SshHostKeyFingerprint` | No | — | SSH host key fingerprint for verification |
+| `-RenamePattern` | No | — | Regex pattern to match in filename for renaming before upload |
+| `-RenameReplacement` | No | — | Replacement string for `-RenamePattern` (supports capture groups like `$1`) |
 | `-Recurse` | No | `false` | Scan subdirectories |
 | `-DeleteAfterTransfer` | No | `false` | Delete local files after successful upload |
 | `-DryRun` | No | `false` | Preview transfers without uploading |
@@ -125,6 +127,30 @@ The `-FileFilter` parameter uses PowerShell regex (case-insensitive by default).
     -Recurse -FileFilter '\.pdf$'
 ```
 
+## Renaming Files Before Upload
+
+Use `-RenamePattern` (regex) and `-RenameReplacement` together to rename files on the remote side without touching the local files.
+
+| Goal | Pattern | Replacement |
+|------|---------|-------------|
+| Add date before extension | `'^(.+?)(\.[^.]+)$'` | `'${1}_20260416${2}'` |
+| Add prefix | `'^'` | `'processed_'` |
+| Add suffix before extension | `'^(.+?)(\.[^.]+)$'` | `'${1}_done${2}'` |
+| Strip `_draft` from name | `'_draft'` | `''` |
+| Replace spaces with underscores | `' '` | `'_'` |
+
+Rename uses PowerShell's `-replace` operator (regex, case-insensitive). The local file is **not** modified — only the remote destination path changes.
+
+### Add today's date to every filename
+```powershell
+$date = Get-Date -Format 'yyyyMMdd'
+.\Send-FilesToSftp.ps1 -LocalPath "C:\exports" -RemotePath "/incoming" `
+    -HostName "sftp.example.com" -UserName "uploader" `
+    -RenamePattern '^(.+?)(\.[^.]+)$' -RenameReplacement "${date}_`$1`$2"
+```
+
+> **Tip:** Use `-DryRun` first to preview the renamed remote paths before committing to the transfer.
+
 ## SSH Host Key Fingerprint
 
 For production use, always provide the host key fingerprint to prevent MITM attacks: