Develop Reference

C# Console app need assistance with main args error

I have the following c# Console app I would run this in ssis but i am using a couple of PDF manipulating librarys. so i am going to call an exe from my ssis package while passing in a file path.
But i am getting the following error when trying to run via the exe.
Unhandled Exception: System.IndexOutOfRangeException: Index was
outside the bounds of the array. at ConsoleApp.program.Main(String[]
args) line 87
BUT if i run in debug it works fine. Once i get it working on its own via the exe, i want to pass the filepath as a parameter in ssis.
see c# below
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using org.apache.pdfbox.pdmodel;
using org.apache.pdfbox.util;
using System.IO;
namespace PDF_Read_ConsoleApp
{
class Program
{
public static void FilePath(string path)
{
//Console.WriteLine("Please enter full pdf path \n\n ");
//path = Console.ReadLine();
string fp;
fp = #path;
string[] files = Directory.GetFiles(path, "*.pdf");
foreach (string s in files)
{
string txtOutput = s.Replace(".pdf", ".txt");
if (File.Exists(txtOutput))
{
File.Delete(txtOutput);
}
string output;
PDDocument doc = null;
try
{
doc = PDDocument.load(s);
PDFTextStripper stripper = new PDFTextStripper();
stripper.getText(doc);
output = stripper.getText(doc);
StreamWriter NewFile;
NewFile = new StreamWriter(txtOutput);
//NewFile.Write(output.ToString());
NewFile.Write(output.ToString());
NewFile.Close();
}
finally
{
//if (doc != null)
//{
doc.close();
// Console.WriteLine("\n\n File saveed - ({0} ", txtOutput);
//}
}
}
}
static void Main(string[] args)
{
args[0] = #"C:\SSIS_Packages\PDF_Import\PDF_Import\PO_pdfs"; //// TESTING FILE PATH1
FilePath(args[0]);
}
}
}
Kind Regards
Rob

I have managed to get it working, I need to enter an argument within the debug screen, see information in URL below
Console app arguments, how arguments are passed to Main method
THank you for everyone's comments

How to use the gRPC tools to generate code

I've read the tutorial and I'm able to generate the .cs file but it doesn't include any of my service or rpc definitions.
I've added protoc to my PATH and from inside the project directory.
protoc project1.proto --csharp_out="C:\output" --plugin=protoc-gen-grpc="c:\Users\me\.nuget\packages\grpc.tools\1.8.0\tools\windows_x64\grpc_csharp_plugin.exe"
No errors output in console

You need to add the --grpc_out command line option, e.g. add
--grpc_out="C:\output\"
Note that it won't write any files if you don't have any services.
Here's a complete example. From a root directory, create:
An empty output directory
A tools directory with protoc.exe and grpc_csharp_plugin.exe
A protos directory with test.proto as shown below:
test.proto:
syntax = "proto3";
service StackOverflowService {
rpc GetAnswer(Question) returns (Answer);
}
message Question {
string text = 1;
string user = 2;
repeated string tags = 3;
}
message Answer {
string text = 1;
string user = 2;
}
Then run (all on one line; I've broken it just for readability here):
tools\protoc.exe -I protos protos\test.proto --csharp_out=output
--grpc_out=output --plugin=protoc-gen-grpc=tools\grpc_csharp_plugin.exe
In the output directory, you'll find Test.cs and TestGrpc.cs

Just an idle comment here for other that find this, the documentation about this is terribly out of date and just flat out wrong.
Installing Grpc.Tools does not install anything in a packages folder; that is legacy behaviour which is no longer true even on windows.
When you install Grpc.Tools it will be hidden away in your local package cache, which you can see by calling:
$ dotnet nuget locals all --list
info : http-cache: /Users/doug/.local/share/NuGet/v3-cache
info : global-packages: /Users/doug/.nuget/packages/
info : temp: /var/folders/xx/s2hnzbrj3yn4hp1bg8q9gb_m0000gn/T/NuGetScratch
The binaries you want will be in one of these folders.
The easiest way to do this is to download the Grpc.Tools package directly from nuget, and install it locally.
I've hacked up this little helper script to do that, which works on windows/mac/linux, which may ease the difficulty of getting starting with this for others:
using System;
using System.Diagnostics;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Net.Http;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Threading.Tasks;
using Mono.Unix;
namespace BuildProtocol
{
public class Program
{
private const string ToolsUrl = "https://www.nuget.org/api/v2/package/Grpc.Tools/";
private const string Service = "Greeter";
private static string ProtocolPath = Path.Combine("..", "protos");
private static string Protocol = Path.Combine(ProtocolPath, "helloworld.proto");
private static string Output = Path.Combine("..", "Greeter");
public static void Main(string[] args)
{
RequireTools().Wait();
var protoc = ProtocPath();
var plugin = ProtocPluginPath();
Console.WriteLine($"Using: {protoc}");
Console.WriteLine($"Using: {plugin}");
var command = new string[]
{
$"-I{ProtocolPath}",
$"--csharp_out={Output}",
$"--grpc_out={Output}",
$"--plugin=protoc-gen-grpc=\"{plugin}\"",
Protocol,
};
Console.WriteLine($"Exec: {protoc} {string.Join(' ', command)}");
var process = new Process
{
StartInfo = new ProcessStartInfo
{
UseShellExecute = false,
FileName = protoc,
Arguments = string.Join(' ', command)
}
};
process.Start();
process.WaitForExit();
Console.WriteLine($"Completed status: {process.ExitCode}");
}
public static async Task RequireTools()
{
if (!Directory.Exists("Tools"))
{
Console.WriteLine("No local tools found, downloading binaries from nuget...");
Directory.CreateDirectory("Tools");
await DownloadTools();
ExtractTools();
}
}
private static void ExtractTools()
{
ZipFile.ExtractToDirectory(Path.Combine("Tools", "tools.zip"), Path.Combine("Tools", "bin"));
}
private static async Task DownloadTools()
{
using (var client = new HttpClient())
{
Console.WriteLine($"Fetching: {ToolsUrl}");
using (var result = await client.GetAsync(ToolsUrl))
{
if (!result.IsSuccessStatusCode) throw new Exception($"Unable to download tools ({result.StatusCode}), check URL");
var localArchive = Path.Combine("Tools", "tools.zip");
Console.WriteLine($"Saving to: {localArchive}");
File.WriteAllBytes(localArchive, await result.Content.ReadAsByteArrayAsync());
}
}
}
private static string ProtocPath()
{
var path = Path.Combine("Tools", "bin", "tools", DetermineArch(), "protoc");
RequireExecutablePermission(path);
return WithExeExtensionIfRequired(path);
}
private static string ProtocPluginPath()
{
var path = Path.Combine("Tools", "bin", "tools", DetermineArch(), "grpc_csharp_plugin");
RequireExecutablePermission(path);
return WithExeExtensionIfRequired(path);
}
private static void RequireExecutablePermission(string path)
{
if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) return;
Console.WriteLine($"Ensuring +x on {path}");
var unixFileInfo = new UnixFileInfo(path);
unixFileInfo.FileAccessPermissions = FileAccessPermissions.UserRead | FileAccessPermissions.UserWrite | FileAccessPermissions.UserExecute;
}
private static string WithExeExtensionIfRequired(string path)
{
if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
path += ".exe";
}
return path;
}
private static string DetermineArch()
{
var arch = RuntimeInformation.OSArchitecture;
if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
return WithArch("windows_", arch);
}
if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX))
{
return WithArch("macosx_", arch);
}
if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
{
return WithArch("linux_", arch);
}
throw new Exception("Unable to determine runtime");
}
private static string WithArch(string platform, Architecture arch)
{
switch (arch)
{
case Architecture.X64:
return $"{platform}x86";
case Architecture.X86:
return $"{platform}x64";
default:
throw new ArgumentOutOfRangeException(nameof(arch), arch, null);
}
}
}
}

the following approach helped me :
Create a gRPC client and server in ASP.NET Core
in project, where .proto file located, edit the .csproj file
<ItemGroup>
....
<Protobuf Include="Shipping.proto" GrpcServices="Server" />
</ItemGroup>
rebuild the project, the all necessary .cs files will be added automaticaly
\obj\Debug\[TARGET_FRAMEWORK]\Shipping.cs
\obj\Debug\[TARGET_FRAMEWORK]\ShippingGrpc.cs

Downoald multiple files on same time

I have Listbox full with links like this: http://example.com/sorted/Avicii/Avicii+-+Wake+Me+Up.mp3 and I wanna download them all on same time any suggestions?
this code I use to download a single file
private void txtUrl_TextChanged(object sender, EventArgs e)
{
try
{
// function that enter the file name automatically in the savefiledialog.
Uri uri = new Uri(txtUrl.Text);
// Save the file name to the string.
filename = Path.GetFileName(uri.LocalPath);
}
catch
{
// no need need an exception message.
}
}
private void DownloadFile(string url, string save)
{
using (var client = new WebClient())
{
// Run code every time the download changes.
client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(Changed);
// Run codes when file download has been completed.
client.DownloadFileCompleted += new AsyncCompletedEventHandler(Completed);
client.DownloadFileAsync(new Uri(url), save);

The solution could look like this:
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
namespace SillyCSharpNameSpace
{
public class VerboseDownloaderClassName
{
private string downloadFile(string url, string localDir)
{
try
{
var localPath = Path.Combine(localDir, Path.GetFileName(url));
using (var wc = new WebClient())
{
wc.DownloadFile(url, localPath);
return localPath;
}
}
catch (Exception e)
{
Console.WriteLine(e);
return null;
}
}
public void DownloadAll(List<string> urls)
{
urls.AsParallel()
.Where(url => !string.IsNullOrWhiteSpace(url))
.WithDegreeOfParallelism(20)
.Select(url => downloadFile(url, "."));
}
}
}
I'm sure if you work with WinForms or ASP.NET you can figure out how to take an url string from a list box item. And note, that Path.GetFileName() works only for the form you have provided - with the file name at the end of URL, without any URL parameters. AsParallel method parallelizes the downloading work into 20 "threads". I think it should be enough for your purpose.
Bonus. This is the same in F#, just because I can ;o)
open System.IO
open System.Net
open FSharp.Collections.ParallelSeq // from NuGet FSharp.Collections.ParallelSeq
let downloadFile dir url =
let localPath = Path.Combine(dir, Path.GetFileName url)
try
use wc = new WebClient()
wc.DownloadFile(url, localPath)
Some localPath
with ex ->
printfn "Can't download file from %s: %A" url ex
None
let downloadAll (urls: string list) =
urls
|> PSeq.withDegreeOfParallelism 20 // 20 threads
|> PSeq.choose (downloadFile ".")

Deleting a VPN Connection

After I disconnect from the vpn using this code System.Diagnostics.Process.Start("rasdial.exe", "My_VPN /d"); It still shows on the VPN Connection list. How can I remove it from there through my program?

If you want to delete VPN connection you need to delete file "rasphone.pbk" or section with [VPN Name] in this file. The file is INI file with extension PBK.
By default the file located in %APPDATA%\Microsoft\Network\Connections\Pbk\rasphone.pbk
After delete operation you will need to restart "explorer.exe"

You can remove it by using WMI's PS_VpnConnection class.
using System.Management; // need to add a reference to the assembly [System.Management]
public class Program
{
public static void Main()
{
const string WMIScope = "root/Microsoft/Windows/RemoteAccess/Client";
const string WMIClass = "PS_VpnConnection";
using (var cls = new ManagementClass(WMIScope, WMIClass, null))
using (var methodParams = cls.GetMethodParameters("Remove"))
{
methodParams["Name"] = new[]{"your_vpn_name"};
methodParams["Force"] = true;
cls.InvokeMethod("Remove", methodParams, null);
}
}
}

C# IO Reading and Writing file in use error

I have a library that handles reading and writing a cache file. This library is used by a Windows Service and several instances of a console application on the same machine. The console application runs when a user logs in.
I am getting occasional IO errors saying the cache file is in use by another process. I assume that collisions are occurring between the different application instances and service trying to read and write at the same time.
Is there a way to lock the file when it is in use and force all other requests to "wait in line" to access the file?
private void SaveCacheToDisk(WindowsUser user) {
string serializedCache = SerializeCache(_cache);
//encryt
serializedCache = AES.Encrypt(serializedCache);
string path = user == null ? ApplicationHelper.CacheDiskPath() :
_registry.GetCachePath(user);
string appdata = user == null ? ApplicationHelper.ClientApplicationDataFolder() :
_registry.GetApplicationDataPath(user);
if (Directory.Exists(appdata) == false) {
Directory.CreateDirectory(appdata);
}
if (File.Exists(path) == false) {
using (FileStream stream = File.Create(path)) { }
}
using (FileStream stream = File.Open(path, FileMode.Truncate)) {
using (StreamWriter writer = new StreamWriter(stream)) {
writer.Write(serializedCache);
}
}
}
private string ReadCacheFromDisk(WindowsUser user) {
//cache file path
string path = user == null ? ApplicationHelper.CacheDiskPath() :
_registry.GetCachePath(user);
using (FileStream stream = File.Open(path, FileMode.Open)) {
using (StreamReader reader = new StreamReader(stream)) {
string serializedCache = reader.ReadToEnd();
//decrypt
serializedCache = AES.Decrypt(serializedCache);
return serializedCache;
}
}
}

Sure, you could use a mutex and permit access only when holding the mutex.

You could use a cross-process EventWaitHandle. This lets you create and use a WaitHandle that's identified across processes by name. A thread is notified when it's its turn, does some work, and then indicates it's done allowing another thread to proceed.
Note that this only works if every process/thread is referring to the same named WaitHandle.
The EventWaitHandle constructors with strings in their signature create named system synchronization events.

One option you could consider is having the console applications route their file access through the service, that way there's only one process accessing the file and you can synchronise access to it there.
One way of implementing this is by remoting across an IPC channel (and here's another example from weblogs.asp.net). We used this technique in a project for the company I work for and it works well, with our specific case providing a way for a .net WebService to talk to a Windows Service running on the same machine.
Sample based on the weblogs.asp.net example
Basically what you need to do with the code below is create a Solution, add two Console Apps (one called "Server" and the other called "Client" and one Library to it. Add a reference to the Library to both console apps, paste the code below in and add a reference to System.Runtime.Remoting to both Server & Console.
Run the Server app, then run the client app. Observe the fact that the server app has a message passed to it by the client. You can extend this to any number of messages/tasks
// Server:
using System;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Ipc;
namespace RemotingSample
{
public class Server
{
public Server()
{
}
public static int Main(string[] args)
{
IpcChannel chan = new IpcChannel("Server");
//register channel
ChannelServices.RegisterChannel(chan, false);
//register remote object
RemotingConfiguration.RegisterWellKnownServiceType(
typeof(RemotingSample.RemoteObject),
"RemotingServer",
WellKnownObjectMode.SingleCall);
Console.WriteLine("Server Activated");
Console.ReadLine();
return 0;
}
}
}
// Client:
using System;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Ipc;
using RemotingSample;
namespace RemotingSample
{
public class Client
{
public Client()
{
}
public static int Main(string[] args)
{
IpcChannel chan = new IpcChannel("Client");
ChannelServices.RegisterChannel(chan);
RemoteObject remObject = (RemoteObject)Activator.GetObject(
typeof(RemotingSample.RemoteObject),
"ipc://Server/RemotingServer");
if (remObject == null)
{
Console.WriteLine("cannot locate server");
}
else
{
remObject.ReplyMessage("You there?");
}
return 0;
}
}
}
// Shared Library:
using System;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
namespace RemotingSample
{
public class RemoteObject : MarshalByRefObject
{
public RemoteObject()
{
Console.WriteLine("Remote object activated");
}
public String ReplyMessage(String msg)
{
Console.WriteLine("Client : " + msg);//print given message on console
return "Server : I'm alive !";
}
}
}

Check out the TextWriter.Synchronized method.
http://msdn.microsoft.com/en-us/library/system.io.textwriter.synchronized.aspx
This should let you do this:
TextWriter.Synchronized(writer).Write(serializedCache);