using System;

using System.Web;

public class Program

{

    public static void Main()

    {

        string url= @"http://localhost:44371/Download/Visualizar?";

        string param = @"fullPath=F:\ERP\ERP Teste\Erp\Visual Master Erp\Documentos\01001001000113\Boletos\1_1_CNAB240.PDF";

        Console.WriteLine(url + param);

        string novaUrl = url + HttpUtility.UrlEncode(param);

        Console.WriteLine(novaUrl);

        Console.WriteLine(HttpUtility.UrlDecode(novaUrl));

    }

}