Get XML and/or HTML from file. Return the values of the supplied attribute name.

GetAttributeValues.cs

using System;
using System.IO;
using System.Text.RegularExpressions;

class GetAttributeValues
{
	public static void Main()
	{
		// Program settings (at top for convenience since they're most likely to be modified).
		string attributeName = "name";
		string attributeValueRegex = @"(?<=\b" + attributeName + @"="")[^""]*";
		string filePath = @"C:\xml.txt";

		// Open file containing HTML and/or XML tags.
		using (var streamReader = new StreamReader(filePath))
		{
			// Variable for holding line of text from file.
			string line;

			// Read the file line by line.
			while ((line = streamReader.ReadLine()) != null)
				// Write the attribute value to the console.
				Console.WriteLine(GetRegexMatch(line, attributeValueRegex));
		}

		// Suspend the screen.
		Console.ReadKey();
	}

	public static string GetRegexMatch(string text, string regexPattern)
	{
		// Instantiate regex object and execute.
		Regex regex = new Regex(regexPattern);
		Match match = regex.Match(text);

		// Return the matched text.
		return match.Value;
	}
}