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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Text.RegularExpressions;

public class Program
{
	public static void Main()
	{
		var map = new Dictionary<string, object>()
		{
			{ "Param1", true },
			{ "Param2", "\"False\"" },
			{ "Param3", 123 },
			{ "Param4", "\"1234\"" },
		};
		
		var script = " I have Param1 and Param2 and Param3 and Param4 ";
		MatchCollection matches = Regex.Matches(script, "Param\\d+");
		foreach (Match match in matches)
		{
			object val = map[match.Value];
			script = script.Replace(match.Value, val is bool ? val.ToString().ToLower() : val.ToString());
		}
		
		Console.WriteLine(script);
	}
}