IP Address Lookup Tool (PowerShell GUI)

A user-friendly PowerShell application for performing IP address hostname lookups via a graphical interface. Built by Ryan Johnson.

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Features

• Three operational modes:

  • Single IP Mode: Look up a single IP address manually
  • Text File Mode: Upload a .txt file of IPs and bulk check all entries
  • Manual Bulk Mode: Manually add IPs one-by-one and bulk check them

• CSV Export Support: Lookup results are saved as a structured CSV file

• Intuitive GUI: Made with Windows Forms (System.Windows.Forms) for a simple and accessible user interface

• Input Validation: Built-in regex filter to verify valid IPv4 addresses

• Safe File Handling: Cleans whitespace in text file mode and gracefully handles invalid input or unresolved hostnames

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GUI Overview

Control	Function
Check Text File	Load a .txt file containing IP addresses to look up
Check Single IP	Input one IP address to resolve
Check Bulk Manually	Add IPs one-by-one via textbox and export all at once
Browse Buttons	Browse and select input/output paths
Run	Executes the lookup and writes results to the designated output
Add/Clear (Manual Mode)	Add IPs to the list or reset the entry array
Output Box	Displays real-time status messages and lookup results

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How It Works

• Uses [System.Net.Dns]::GetHostEntry() to resolve each IP to a hostname
• Catches and logs resolution errors (including invalid formats)
• Saves output as a .csv file at the selected path

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Built With

• PowerShell
• Windows Forms GUI (System.Windows.Forms)
• .NET assemblies
• Regex for IP validation

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File Output Example

"IPAddress","Hostname"
"8.8.8.8","dns.google"
"1.1.1.1","one.one.one.one"
"256.256.256.256","Invalid IP Format"