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Accessing a .ToList() from a c# Class Library using Async Task Main

I have had a static version of this type of code working in a static version. However the API calls were just incredibly slow. I am trying to move to asynchronous now that C# 7 supports console async tasks (where I add code to connect to my DB and store data. I want to see this code output on the console to ensure it's working so I can assign variables for loading. I can't seem to figure out how to access the list from main. Here is the code I have so far:
Wrapper (or C# library):
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Threading.Tasks;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
namespace AlphaVantageApiWrapper
{
public static class AlphaVantageApiWrapper
{
public static async Task<AlphaVantageRootObject> GetTechnical(List<ApiParam> parameters, string apiKey)
{
var stringRequest = parameters.Aggregate(#"https://www.alphavantage.co/query?", (current, param) => current + param.ToApiString());
stringRequest += "&apikey=" + apiKey;
var apiData = await CallAlphaVantageApi(stringRequest);
var technicalsObject = new AlphaVantageRootObject
{
MetaData = new MetaData
{
Function = parameters.FirstOrDefault(x => x.ParamName.Equals("function"))?.ParamValue ?? "NA?",
Interval = parameters.FirstOrDefault(x => x.ParamName.Equals("interval"))?.ParamValue ?? "NA?",
SeriesType = parameters.FirstOrDefault(x => x.ParamName.Equals("series_type"))?.ParamValue ?? "NA?",
Symbol = parameters.FirstOrDefault(x => x.ParamName.Equals("symbol"))?.ParamValue ?? "NA?"
},
TechnicalsByDate = apiData.Last.Values().OfType<JProperty>().Select(x => new TechnicalDataDate
{
Date = Convert.ToDateTime(x.Name),
Data = x.Value.OfType<JProperty>().Select(r => new TechnicalDataObject
{
TechnicalKey = r.Name,
TechnicalValue = Convert.ToDouble(r.Value.ToString())
}).ToList()
})
.ToList()
};
return technicalsObject;
}
public class ApiParam
{
public string ParamName;
public string ParamValue;
public ApiParam(string paramNameIn, string paramValueIn)
{
ParamName = paramNameIn;
ParamValue = paramValueIn;
}
public string ToApiString()
{
return $"&{ParamName}={ParamValue}";
}
}
public static string ToDescription(this Enum enumeration)
{
var type = enumeration.GetType();
var memInfo = type.GetMember(enumeration.ToString());
if (memInfo.Length <= 0) return enumeration.ToString();
var attrs = memInfo[0].GetCustomAttributes(typeof(EnumDescription), false);
return attrs.Length > 0 ? ((EnumDescription)attrs[0]).Text : enumeration.ToString();
}
public static async Task<JObject> CallAlphaVantageApi(string stringRequest)
{
try
{
using (var client = new HttpClient())
{
var res = await client.GetStringAsync(stringRequest);
return JsonConvert.DeserializeObject<JObject>(res);
}
}
catch (Exception e)
{
//fatal error
return null;
}
}
public class AlphaVantageRootObject
{
public MetaData MetaData;
public List<TechnicalDataDate> TechnicalsByDate;
}
public class MetaData
{
public string Function;
public string Interval;
public string SeriesType;
public string Symbol;
}
public class TechnicalDataDate
{
public DateTime Date;
public List<TechnicalDataObject> Data;
}
public class TechnicalDataObject
{
public string TechnicalKey { get; set; }
public double TechnicalValue { get; set; }
}
public class EnumDescription : Attribute
{
public string Text { get; }
public EnumDescription(string text)
{
Text = text;
}
}
public enum AvFuncationEnum
{
[EnumDescription("SMA")] Sma,
[EnumDescription("EMA")] Ema,
[EnumDescription("MACD")] Macd,
[EnumDescription("STOCH")] Stoch,
[EnumDescription("RSI")] Rsi,
}
public enum AvIntervalEnum
{
[EnumDescription("1min")] OneMinute,
[EnumDescription("5min")] FiveMinutes,
[EnumDescription("15min")] FifteenMinutes,
[EnumDescription("30min")] ThirtyMinutes,
[EnumDescription("60min")] SixtyMinutes,
[EnumDescription("daily")] Daily,
[EnumDescription("weekly")] Weekly,
[EnumDescription("monthly")] Monthly
}
public enum AvSeriesType
{
[EnumDescription("close")] Close,
[EnumDescription("open")] Open,
[EnumDescription("high")] High,
[EnumDescription("low")] Low,
}
}
}
`
The c# async main task (which obviously isn't working)...
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace AlphaVantageApiWrapper.Test
{
public static class AlphaVantageApiDbLoader
{
public static async Task Main(string[] args)
{
var API_KEY = "EnterAPIHERE";
var StockTickers = new List<string> { "AAPL" }; //eventualy becomes a list pulled in from the DB for processing
foreach (var ticker in StockTickers)
{
var parameters = new List<AlphaVantageApiWrapper.ApiParam>
{
new AlphaVantageApiWrapper.ApiParam("function", AlphaVantageApiWrapper.AvFuncationEnum.Sma.ToDescription()),
new AlphaVantageApiWrapper.ApiParam("symbol", ticker),
new AlphaVantageApiWrapper.ApiParam("interval", AlphaVantageApiWrapper.AvIntervalEnum.Daily.ToDescription()),
new AlphaVantageApiWrapper.ApiParam("time_period", "5"),
new AlphaVantageApiWrapper.ApiParam("series_type", AlphaVantageApiWrapper.AvSeriesType.Open.ToDescription()),
};
//Start Collecting SMA values
var SMA_5 = await AlphaVantageApiWrapper.GetTechnical(parameters, API_KEY);
///var SMA_5Result = AlphaVantageApiWrapper.TechnicalDataObject() // can't all method error just want values fron list
parameters.FirstOrDefault(x => x.ParamName == "time_period").ParamValue = "20";
var SMA_20 = await AlphaVantageApiWrapper.GetTechnical(parameters, API_KEY);
parameters.FirstOrDefault(x => x.ParamName == "time_period").ParamValue = "50";
var SMA_50 = await AlphaVantageApiWrapper.GetTechnical(parameters, API_KEY);
parameters.FirstOrDefault(x => x.ParamName == "time_period").ParamValue = "200";
var SMA_200 = await AlphaVantageApiWrapper.GetTechnical(parameters, API_KEY);
//Change function to EMA
//Change function to RSI
//Change function to MACD
}
}
}
}
Any help would be greatly appreciated! I know the code runs in the background, I just can't seem to get it to a point to view it on the console screen. Eventually I would assign the symbol, date, value returned variable and read these to a DB. I'm used to using DataTables, but the async and .ToList is new to me. Thanks!!

Can you use SignalR without using Knockout?

All I need is to update a page with alerts when someone else creates one. Wouldn't have to be real time, but every 10 seconds or so minimum. It also needs to flash the tab when something is new is displayed for the user to know something was updated if they are currently on a different page. Thank you.

I've never tried to use knockout with signalR, this is how we do it with near-0 latency.
In our masterpage we include the jquery signalR library
Underneath, we tell it to include the signalR auto-generated script
our Hub class looks like so.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.AspNet.SignalR;
using Microsoft.AspNet.SignalR.Hubs;
namespace CHSI.Shared.APIs
{
[HubName("applicationMessageHub")]
public class ApplicationMessageHub : Hub
{
private readonly TimeSpan _updateInterval = TimeSpan.FromMilliseconds(5000);
private IList< DSIDGroup> DSIDGroups = new List<DSIDGroup>();
public ApplicationMessageHub()
{
}
public void CheckMessages(object state)
{
GetMessages();
}
public Models.ApplicationMessage GetCurrentMessage(int DSID)
{
Models.ApplicationMessage currentMessage = null;
return currentMessage;
}
public override Task OnConnected()
{
string DSID = Context.QueryString["DSID"];
if (!string.IsNullOrEmpty(DSID))
{
Groups.Add(Context.ConnectionId, DSID);
DSIDGroup currentGroup = (from g in this.DSIDGroups where g.DSID == DSID select g).FirstOrDefault();
if (currentGroup != null)
{
currentGroup.ConnecedIDs.Add(Context.ConnectionId);
}
else
{
currentGroup = new DSIDGroup();
currentGroup.DSID = DSID;
currentGroup.ConnecedIDs.Add(Context.ConnectionId);
this.DSIDGroups.Add(currentGroup);
}
}
return base.OnConnected();
}
public override Task OnDisconnected(bool stopCalled)
{
foreach (var DSIDgroup in DSIDGroups)
{
if (DSIDgroup.ConnecedIDs.Contains(Context.ConnectionId))
{
DSIDgroup.ConnecedIDs.Remove(Context.ConnectionId);
if (DSIDgroup.ConnecedIDs.Count == 0)
{
DSIDGroups.Remove(DSIDgroup);
}
break;
}
}
return base.OnDisconnected(stopCalled);
}
public void BroadcastMessage(Models.ApplicationMessage message)
{
Clients.All.SendMessage(message);
}
public void clearCache(int DSID)
{
Clients.Group(DSID.ToString()).clearCache();
}
public Models.ApplicationMessage GetMessages()
{
foreach (var group in this.DSIDGroups)
{
Models.ApplicationMessage currentMessage = GetCurrentMessage(Convert.ToInt32(group.DSID));
if (currentMessage != null)
{
Clients.Group(group.DSID).SendMessage(currentMessage);
}
}
return null;
//return _applicationMessage.GetCurrentMessage();
}
}
public class DSIDGroup
{
public string DSID {get;set;}
public IList<string> ConnecedIDs { get;set; }
public DSIDGroup()
{
this.ConnecedIDs = new List<string>();
}
}
}
This class handles grouping my users into groups based on their account (DSID), but you could group users by chat room, not at all, or some other methodology.
We also call javascript functions elsewhere in the codebase like so.
var context = Microsoft.AspNet.SignalR.GlobalHost.ConnectionManager.GetHubContext<CHSI.Shared.APIs.ApplicationMessageHub>();
List<string> dsids = new List<string>();
dsids.Add(CHSI.Shared.Models.ConnectionManager.Current().CurrentDSID.Value.ToString());
context.Clients.Groups(dsids).clearCache();
There is a javascript function called SendMessage and another called clearCache which handles those calls.
They're defined like so.
applicationMessageHub.client.sendMessage = function (message) {
alert(message.SummaryMessage);
};
applicationMessageHub.client.clearCache = function () {
localStorage.removeItem("companiesCache");
Class.loadPage(Class);
}
I hope this helps!

Replacing dll at runtime without pain

I have a basic WinForm Solution (MS VS2013, .Net framework 4.5) for test some methods included in a Dll, using Reflection. My goal is test the main application that it can run two methods of Dll (without referencing the dll in project), and later, run four methods (2 methods added) without stop the main application and run it again, using reflection.
Reflections works fine (if I stop the main application, replacing the dll file and run the main application again, all works fine), but I can't replace the dll at runtime.
The main application has a Timer control with an interval of 60 seconds. Every 60 seconds, a method is executed that checks if a DLL file is in a folder. If a DLL file exists in that folder, I want to use the new DLL in the main application (running) because the new DLL contains old methods (first DLL) and additional methods that the main application needs.
However, I am getting an error that the file is in use.
I have read several posts, questions, answers, MEF documentation, AppDomains related, but I have been unable to concatenate the information to be able to implement a solution.
Actually, I thought a lot before post this question, but I confess that I prefer to spend a moment of shame, knowing that you can give me a hand.
It would be for me a great help if you help me with code and specific instructions.
This is the code:
Main application:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Reflection;
using System.IO;
namespace testDLLs
{
public partial class Principal : Form
{
public Principal()
{
InitializeComponent();
}
private void Principal_Load(object sender, EventArgs e)
{
labelVersionDll.Text = metodosApoyo.RunDLLFunction("VersionOperaciones");
string cListaOperaciones = metodosApoyo.RunDLLFunction("ListaOperaciones");
string[] aOperaciones = cListaOperaciones.Split('|');
comboBoxOperaciones.Items.Clear();
foreach (string cOperacion in aOperaciones)
{
comboBoxOperaciones.Items.Add(cOperacion);
}
timerForUpdate.Interval = 60000;
timerForUpdate.Enabled = true;
}
private void buttonRun_Click(object sender, EventArgs e)
{
int iOperador1, iOperador2;
string resultadoDesdeDll = null;
string cOperacionSeleccionada;
Int32.TryParse(textBoxOperador1.Text, out iOperador1);
Int32.TryParse(textBoxOperador2.Text, out iOperador2);
cOperacionSeleccionada = comboBoxOperaciones.GetItemText(comboBoxOperaciones.SelectedItem);
object[] parametersArray = new object[] { iOperador1, iOperador2 };
resultadoDesdeDll = metodosApoyo.RunDLLFunction(cOperacionSeleccionada, parametersArray);
textBoxResultado.Text = resultadoDesdeDll;
}
private void timerForUpdate_Tick(object sender, EventArgs e)
{
labelUpdateStatus.Text = "Checking updates ...";
notifyIconUpdate.Visible = true;
notifyIconUpdate.BalloonTipText = "Instalando nuevo DLL....";
notifyIconUpdate.BalloonTipTitle = "Info:";
notifyIconUpdate.ShowBalloonTip(5000);
if (File.Exists(#"C:\DLLsForCopy\OperacionesDLL.dll"))
{
File.Copy(#"C:\DLLsForCopy\OperacionesDLL.dll", #"D:\DLLs\OperacionesDLL.dll", true);
labelVersionDll.Text = metodosApoyo.RunDLLFunction("VersionOperaciones");
string cListaOperaciones = metodosApoyo.RunDLLFunction("ListaOperaciones");
string[] aOperaciones = cListaOperaciones.Split('|');
comboBoxOperaciones.Items.Clear();
foreach (string cOperacion in aOperaciones)
{
comboBoxOperaciones.Items.Add(cOperacion);
}
}
labelUpdateStatus.Text = "";
notifyIconUpdate.Visible = false;
}
}
}
Class in project, for some functions for Main application:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Reflection;
namespace testDLLs
{
class metodosApoyo
{
public static string RunDLLFunction(string cMetodo, object[] aParametros = null)
{
string cRetornoGlobal = "";
Object resultado = null;
string cOperacionSeleccionada = cMetodo;
Assembly assembly = Assembly.LoadFile(#"D:\DLLs\OperacionesDLL.dll");
Type type = assembly.GetType("OperacionesDLL.Operaciones");
MethodInfo methodInfo = type.GetMethod(cOperacionSeleccionada);
ParameterInfo[] parameters = methodInfo.GetParameters();
object classInstance = Activator.CreateInstance(type, null);
object[] parametersArray = null;
if (aParametros != null)
{
parametersArray = new object[aParametros.Length];
int i = 0;
foreach (object value in aParametros)
{
parametersArray[i] = aParametros[i];
i++;
}
}
resultado = methodInfo.Invoke(methodInfo, parametersArray);
cRetornoGlobal = (string)resultado;
return cRetornoGlobal;
}
}
}
DLL source (OperacionesDLL.dll):
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace OperacionesDLL
{
public class Operaciones
{
public static string VersionOperaciones()
{
string retorno;
retorno = "1.0701-16";
return retorno;
}
public static string ListaOperaciones()
{
string retorno;
retorno = "Suma|Resta|Multiplicación|División";
return retorno;
}
public static string Suma(int operador1, int operador2)
{
int resultado;
string retorno;
resultado = operador1 + operador2;
retorno = resultado.ToString();
return retorno;
}
public static string Resta(int operador1, int operador2)
{
int resultado;
string retorno;
resultado = operador1 - operador2;
retorno = resultado.ToString();
return retorno;
}
public static string Multiplicación(int operador1, int operador2)
{
int resultado;
string retorno;
resultado = operador1 * operador2;
retorno = resultado.ToString();
return retorno;
}
public static string División(int operador1, int operador2)
{
int resultado;
string retorno;
resultado = operador1 / operador2;
retorno = resultado.ToString();
return retorno;
}
}
}
Thanks in advance.

You can do what you're describing by using the Managed Addin Framework (MAF) in the System.Addin namespace. I've used it to write apps that scans a folder for DLLs and dynamically loads them. You can also use it to unload and reload DLLs as they appear and disappear from the folder.

3rd party Pdf library significantly slower when running NUnit

I am evaluating Winnovative's PdfToText library and have run into something that concerns me.
Everything runs fine and I am able to extract the text content from a small 20k or less pdf immediately if I am running a console application. However, if I call the same code from the NUnit gui running it takes 15-25 seconds (I've verified it's PdfToText by putting a breakpoint on the line that extracts the text and hitting F10 to see how long it takes to advance to the next line).
This concerns me because I'm not sure where to lay blame since I don't know the cause. Is there a problem with NUnit or PdfToText? All I want to do is extract the text from a pdf, but 20 seconds is completely unreasonable if I'm going to see this behavior under certain conditions. If it's just when running NUnit, that's acceptable, but otherwise I'll have to look elsewhere.
It's easier to demonstrate the problem using a complete VS Solution (2010), so here's the link to make it easier to setup and run (no need to download NUnit or PdfToText or even a sample pdf):
http://dl.dropbox.com/u/273037/PdfToTextProblem.zip (You may have to change the reference to PdfToText to use the x86 dll if you're running on a 32-bit machine).
Just hit F5 and the NUnit Gui runner will load.
I'm not tied to this library, if you have suggestions, I've tried iTextSharp (way too expensive for 2 lines of code), and looked at Aspose (I didn't try it, but the SaaS license is $11k). But they either lack the required functionality or are way too expensive.

(comment turned into answer)
How complex are your PDFs? The 4.1.6 version of iText allows for a closed sourced solution. Although 4.1.6 doesn't directly have a text extractor it isn't too terribly hard to write one using the PdfReader and GetPageContent().

Below is the code I used to extract the text from the PDF using iTextSharp v4.1.6. If it seems overly verbose, it's related to how I'm using it and the flexibility required.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using iTextSharp.text.pdf;
namespace ClassLibrary1
{
public class PdfToken
{
private PdfToken(int type, string value)
{
Type = type;
Value = value;
}
public static PdfToken Create(PRTokeniser tokenizer)
{
return new PdfToken(tokenizer.TokenType, tokenizer.StringValue);
}
public int Type { get; private set; }
public string Value { get; private set; }
public bool IsOperand
{
get
{
return Type == PRTokeniser.TK_OTHER;
}
}
}
public class PdfOperation
{
public PdfOperation(PdfToken operationToken, IEnumerable<PdfToken> arguments)
{
Name = operationToken.Value;
Arguments = arguments;
}
public string Name { get; private set; }
public IEnumerable<PdfToken> Arguments { get; private set; }
}
public interface IPdfParsingStrategy
{
void Execute(PdfOperation op);
}
public class PlainTextParsingStrategy : IPdfParsingStrategy
{
StringBuilder text = new StringBuilder();
public PlainTextParsingStrategy()
{
}
public String GetText()
{
return text.ToString();
}
#region IPdfParsingStrategy Members
public void Execute(PdfOperation op)
{
// see Adobe PDF specs for additional operations
switch (op.Name)
{
case "TJ":
PrintText(op);
break;
case "Tm":
SetMatrix(op);
break;
case "Tf":
SetFont(op);
break;
case "S":
PrintSection(op);
break;
case "G":
case "g":
case "rg":
SetColor(op);
break;
}
}
#endregion
bool newSection = false;
private void PrintSection(PdfOperation op)
{
text.AppendLine("------------------------------------------------------------");
newSection = true;
}
private void PrintNewline(PdfOperation op)
{
text.AppendLine();
}
private void PrintText(PdfOperation op)
{
if (newSection)
{
newSection = false;
StringBuilder header = new StringBuilder();
PrintText(op, header);
}
PrintText(op, text);
}
private static void PrintText(PdfOperation op, StringBuilder text)
{
foreach (PdfToken t in op.Arguments)
{
switch (t.Type)
{
case PRTokeniser.TK_STRING:
text.Append(t.Value);
break;
case PRTokeniser.TK_NUMBER:
text.Append(" ");
break;
}
}
}
String lastFont = String.Empty;
String lastFontSize = String.Empty;
private void SetFont(PdfOperation op)
{
var args = op.Arguments.ToList();
string font = args[0].Value;
string size = args[1].Value;
//if (font != lastFont || size != lastFontSize)
// text.AppendLine();
lastFont = font;
lastFontSize = size;
}
String lastX = String.Empty;
String lastY = String.Empty;
private void SetMatrix(PdfOperation op)
{
var args = op.Arguments.ToList();
string x = args[4].Value;
string y = args[5].Value;
if (lastY != y)
text.AppendLine();
else if (lastX != x)
text.Append(" ");
lastX = x;
lastY = y;
}
String lastColor = String.Empty;
private void SetColor(PdfOperation op)
{
lastColor = PrintCommand(op).Replace(" ", "_");
}
private static string PrintCommand(PdfOperation op)
{
StringBuilder text = new StringBuilder();
foreach (PdfToken t in op.Arguments)
text.AppendFormat("{0} ", t.Value);
text.Append(op.Name);
return text.ToString();
}
}
}
And here's how I call it:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using iTextSharp.text.pdf;
namespace ClassLibrary1
{
public class PdfExtractor
{
public static string GetText(byte[] pdfBuffer)
{
PlainTextParsingStrategy strategy = new PlainTextParsingStrategy();
ParsePdf(pdfBuffer, strategy);
return strategy.GetText();
}
private static void ParsePdf(byte[] pdf, IPdfParsingStrategy strategy)
{
PdfReader reader = new PdfReader(pdf);
for (int i = 1; i <= reader.NumberOfPages; i++)
{
byte[] page = reader.GetPageContent(i);
if (page != null)
{
PRTokeniser tokenizer = new PRTokeniser(page);
List<PdfToken> parameters = new List<PdfToken>();
while (tokenizer.NextToken())
{
var token = PdfToken.Create(tokenizer);
if (token.IsOperand)
{
strategy.Execute(new PdfOperation(token, parameters));
parameters.Clear();
}
else
{
parameters.Add(token);
}
}
}
}
}
}
}

Way to determine framework version without Registry

I've searching a long time, but i couldn't find answer.
Is there any way to determine framework and service pack .NET installed on PC, without access to registry in C#?
I can use registry keys, but i have to do this without access to registry.
I read something about directories in C:\Windows\Microsoft .NET, but there, I only found framework version, nothing about SP. But I need framework and Service Pack.
Can somebody help me?
Regards, Greg

string clrVersion = System.Environment.Version.ToString();
string dotNetVersion = Assembly
.GetExecutingAssembly()
.GetReferencedAssemblies()
.Where(x => x.Name == "mscorlib").First().Version.ToString();

you could use WMI to get a list of all the installed software filtering the result to achieve your goal
public static class MyClass
{
public static void Main()
{
ManagementObjectSearcher mos = new ManagementObjectSearcher("SELECT * FROM Win32_Product");
foreach (ManagementObject mo in mos.Get())
{
Console.WriteLine(mo["Name"]);
}
}
}

I think it's possible to ask the WMI.
Query for all Win32_Product elements and look for the Name Property contains "Microsoft .NET Framework"
ServicePack information is also provided by WMI.. But I don't know exactly where.

You can do this:
System.Environment.Version.ToString()
(CLR Version only)
or this
from MSDN blog on Updated sample .NET Framework detection code that does more in-depth checking
or this
No registry access. Borrowed from this blog.
using System;
using System.IO;
using System.Security;
using System.Text.RegularExpressions;
namespace YourNameSpace
{
public class SystemInfo
{
private const string FRAMEWORK_PATH = "\\Microsoft.NET\\Framework";
private const string WINDIR1 = "windir";
private const string WINDIR2 = "SystemRoot";
public static string FrameworkVersion
{
get
{
try
{
return getHighestVersion(NetFrameworkInstallationPath);
}
catch (SecurityException)
{
return "Unknown";
}
}
}
private static string getHighestVersion(string installationPath)
{
string[] versions = Directory.GetDirectories(installationPath, "v*");
string version = "Unknown";
for (int i = versions.Length - 1; i >= 0; i--)
{
version = extractVersion(versions[i]);
if (isNumber(version))
return version;
}
return version;
}
private static string extractVersion(string directory)
{
int startIndex = directory.LastIndexOf("\\") + 2;
return directory.Substring(startIndex, directory.Length - startIndex);
}
private static bool isNumber(string str)
{
return new Regex(#"^[0-9]+\.?[0-9]*$").IsMatch(str);
}
public static string NetFrameworkInstallationPath
{
get { return WindowsPath + FRAMEWORK_PATH; }
}
public static string WindowsPath
{
get
{
string winDir = Environment.GetEnvironmentVariable(WINDIR1);
if (String.IsNullOrEmpty(winDir))
winDir = Environment.GetEnvironmentVariable(WINDIR2);
return winDir;
}
}
}
}
Here is an improved example that includes service packs,
string path = System.Environment.SystemDirectory;
path = path.Substring( 0, path.LastIndexOf('\\') );
path = Path.Combine( path, "Microsoft.NET" );
// C:\WINDOWS\Microsoft.NET\
string[] versions = new string[]{
"Framework\\v1.0.3705",
"Framework64\\v1.0.3705",
"Framework\\v1.1.4322",
"Framework64\\v1.1.4322",
"Framework\\v2.0.50727",
"Framework64\\v2.0.50727",
"Framework\\v3.0",
"Framework64\\v3.0",
"Framework\\v3.5",
"Framework64\\v3.5",
"Framework\\v3.5\\Microsoft .NET Framework 3.5 SP1",
"Framework64\\v3.5\\Microsoft .NET Framework 3.5 SP1",
"Framework\\v4.0",
"Framework64\\v4.0"
};
foreach( string version in versions )
{
string versionPath = Path.Combine( path, version );
DirectoryInfo dir = new DirectoryInfo( versionPath );
if( dir.Exists )
{
Response.Output.Write( "{0}<br/>", version );
}
}
The problem is that you will have to keep up with the versions as they come out.

You can use the MSI API functions to get a list of all installed products and then check whether the required .NET Framework version is installed.
Just don't tell you boss that these functions will read from the Registry.
Here's the code:
using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Text;
class Program
{
[DllImport("msi.dll", SetLastError = true)]
static extern int MsiEnumProducts(int iProductIndex, StringBuilder lpProductBuf);
[DllImport("msi.dll", CharSet = CharSet.Unicode)]
static extern Int32 MsiGetProductInfo(string product, string property, [Out] StringBuilder valueBuf, ref Int32 len);
public const int ERROR_SUCCESS = 0;
public const int ERROR_MORE_DATA = 234;
public const int ERROR_NO_MORE_ITEMS = 259;
static void Main(string[] args)
{
int index = 0;
StringBuilder sb = new StringBuilder(39);
while (MsiEnumProducts(index++, sb) == 0)
{
var productCode = sb.ToString();
var product = new Product(productCode);
Console.WriteLine(product);
}
}
class Product
{
public string ProductCode { get; set; }
public string ProductName { get; set; }
public string ProductVersion { get; set; }
public Product(string productCode)
{
this.ProductCode = productCode;
this.ProductName = GetProperty(productCode, "InstalledProductName");
this.ProductVersion = GetProperty(productCode, "VersionString");
}
public override string ToString()
{
return this.ProductCode + " - Name: " + this.ProductName + ", Version: " + this.ProductVersion;
}
static string GetProperty(string productCode, string name)
{
int size = 0;
int ret = MsiGetProductInfo(productCode, name, null, ref size); if (ret == ERROR_SUCCESS || ret == ERROR_MORE_DATA)
{
StringBuilder buffer = new StringBuilder(++size);
ret = MsiGetProductInfo(productCode, name, buffer, ref size);
if (ret == ERROR_SUCCESS)
return buffer.ToString();
}
throw new System.ComponentModel.Win32Exception(ret);
}
}
}

This page may be of use:
http://blogs.msdn.com/b/astebner/archive/2009/06/16/9763379.aspx
Although the registry bit is irrelevant to you, the checking using mscoree.dll may be of help - its just that I cant access skydrive from work hence cant look through the code.
Ill see if i find something else.