I want to use the Bluetooth LE functions in .NET Core (specifically, BluetoothLEAdvertisementWatcher) to write a scanner which logs information to a file. This is to run as a desktop application and preferably as a command line app.
Constructors like System.IO.StreamWriter(string) are not available, apparently. How do I create a file and write to it?
I would be just as happy to be able to do a System.Console.WriteLine(string) but that doesn't seem to be available under .NET Core either.
Update: To clarify, if I could have a program that looks like this run without error, I'll be off to the races.
using System;
using Windows.Devices.Bluetooth.Advertisement;
namespace ConsoleApplication
{
public class Program
{
public static void Main(string[] args)
{
BluetoothLEAdvertisementWatcher watcher = new BluetoothLEAdvertisementWatcher();
Console.WriteLine("Hello, world!");
}
}
}
Update 2: Here's the project.json file:
{
"dependencies": {
"Microsoft.NETCore.UniversalWindowsPlatform": "5.0.0"
},
"frameworks": {
"uap10.0": {}
},
"runtimes": {
"win10-arm": {},
"win10-arm-aot": {},
"win10-x86": {},
"win10-x86-aot": {},
"win10-x64": {},
"win10-x64-aot": {}
}
}
The output of the command dotnet -v run contains this error message:
W:\src\dotnet_helloworld>dotnet -v run
...
W:\src\dotnet_helloworld\Program.cs(2,15): error CS0234: The type or namespace name 'Devices' does not exist in the namespace 'Windows' (are you missing an assembly reference?)
...
This code is the skeleton I was looking for when I posed the question. It uses only facilities available in .NET Core.
var watcher = new BluetoothLEAdvertisementWatcher();
var logPath = System.IO.Path.GetTempFileName();
var logFile = System.IO.File.Create(logPath);
var logWriter = new System.IO.StreamWriter(logFile);
logWriter.WriteLine("Log message");
logWriter.Dispose();
This is the solution I'm using. It uses fewer lines of code and does the job just as good. It's also very compatible with .NET core 2.0
using (StreamWriter writer = System.IO.File.AppendText("logfile.txt"))
{
writer.WriteLine("log message");
}
Even better:
using System.IO;
var logPath = Path.GetTempFileName();
using (var writer = File.CreateText(logPath)) // or File.AppendText
{
writer.WriteLine("log message"); //or .Write(), if you wish
}
If writing fewer lines of code is your thing, the above can be re-written as
using (var writer = System.IO.File.CreateText(System.IO.Path.GetTempFileName()))
{
writer.WriteLine("log message"); //or .Write(), if you wish
}
As of today, with RTM, there seems to be this shorter way as well:
var watcher = new BluetoothLEAdvertisementWatcher();
var logPath = System.IO.Path.GetTempFileName();
var logWriter = System.IO.File.CreateText(logPath);
logWriter.WriteLine("Log message");
logWriter.Dispose();
To write to files in .NET Core, you can use two methods:
AppendText()
CreateText()
These two methods are static members of the File class in the System.IO namespace. The difference between them is one appends to an existing file while the other overwrites the file.
Usage examples:
AppendText
using (StreamWriter writer = System.IO.File.AppendText("file.txt"))
{
writer.WriteLine("message");
}
CreateText
using (StreamWriter writer = System.IO.File.CreateText("file.txt"))
{
writer.WriteLine("message");
}
You can get the System.IO references by using the corefx git repository. This will make the StreamWrite(string) constructor you are looking for available.
This repository will also give you the Console.WriteLine(string) function you are looking for.
Here is an async FileWriter class.
using System.IO;
public static class AsyncFileWriter
{
public static async Task WriteToFile(string content)
{
var logPath = #"SOME_PATH\log.txt";
using (var writer = File.CreateText(logPath))
{
await writer.WriteLineAsync(content);
}
}
}
Related
I recently download Nlog.dll from internet and add it into references part of project I'm writing code in C#. But even ready codes doesn't work in my simple console application. For the beginning I write it into my simple console application
As you can see here even some method of ondefined on other panel there is NLog classes located. How I can configure NLog from code?
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using NLog;
using NLog.Config;
namespace ConsoleApplication1
{
class Program
{
private static NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger();
static void Main(string[] args)
{
var config = new NLog.Config.LoggingConfiguration();
var logfile = new NLog.Targets.FileTarget("logfile") { FileName = "file.txt" };
var logconsole = new NLog.Targets.ConsoleTarget("logconsole");
config.AddRule(LogLevel.Info, LogLevel.Fatal, logconsole);
config.AddRule(LogLevel.Debug, LogLevel.Fatal, logfile);
NLog.LogManager.Configuration = config;
var logger = NLog.LogManager.GetCurrentClassLogger();
logger.Info("Hello World");
}
}
}
I get this error (in Russian language):
The code is correct for the latest version of NLog on NuGet. The .dll you downloaded seems to be an older version of NLog.
I have a WPF C# application that contains a button.
The code of the button click is written in separate text file which will be placed in the applications runtime directory.
I want to execute that code placed in the text file on the click of the button.
Any idea how to do this?
Code sample for executing compiled on fly class method:
using System;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;
using System.IO;
using System.Reflection;
using System.Net;
using Microsoft.CSharp;
using System.CodeDom.Compiler;
namespace ConsoleApplication2
{
class Program
{
static void Main(string[] args)
{
string source =
#"
namespace Foo
{
public class Bar
{
public void SayHello()
{
System.Console.WriteLine(""Hello World"");
}
}
}
";
Dictionary<string, string> providerOptions = new Dictionary<string, string>
{
{"CompilerVersion", "v3.5"}
};
CSharpCodeProvider provider = new CSharpCodeProvider(providerOptions);
CompilerParameters compilerParams = new CompilerParameters
{GenerateInMemory = true,
GenerateExecutable = false};
CompilerResults results = provider.CompileAssemblyFromSource(compilerParams, source);
if (results.Errors.Count != 0)
throw new Exception("Mission failed!");
object o = results.CompiledAssembly.CreateInstance("Foo.Bar");
MethodInfo mi = o.GetType().GetMethod("SayHello");
mi.Invoke(o, null);
}
}
}
You can use Microsoft.CSharp.CSharpCodeProvider to compile code on-the-fly. In particular, see CompileAssemblyFromFile.
I recommend having a look at Microsoft Roslyn, and specifically its ScriptEngine class.
Here are a few good examples to start with:
Introduction to the Roslyn Scripting API
Using Roslyn ScriptEngine for a ValueConverter to process user input.
Usage example:
var session = Session.Create();
var engine = new ScriptEngine();
engine.Execute("using System;", session);
engine.Execute("double Sin(double d) { return Math.Sin(d); }", session);
engine.Execute("MessageBox.Show(Sin(1.0));", session);
Looks like someone created a library for this called C# Eval.
EDIT: Updated link to point to Archive.org as it seems like the original site is dead.
What you need is a CSharpCodeProvider Class
There are several samples to understand how does it work.
1 http://www.codeproject.com/Articles/12499/Run-Time-Code-Generation-I-Compile-C-Code-using-Mi
The important point of this example that you can do all things on flay in fact.
myCompilerParameters.GenerateExecutable = false;
myCompilerParameters.GenerateInMemory = false;
2 http://www.codeproject.com/Articles/10324/Compiling-code-during-runtime
This example is good coz you can create dll file and so it can be shared between other applications.
Basically you can search for http://www.codeproject.com/search.aspx?q=csharpcodeprovider&x=0&y=0&sbo=kw&pgnum=6 and get more useful links.
I have a piece of software that generates code for a C# project based on user actions. I would like to create a GUI to automatically compile the solution so I don't have to load up Visual Studio just to trigger a recompile.
I've been looking for a chance to play with Roslyn a bit and decided to try and use Roslyn instead of msbuild to do this. Unfortunately, I can't seem to find any good resources on using Roslyn in this fashion.
Can anyone point me in the right direction?
You can load the solution by using Roslyn.Services.Workspace.LoadSolution. Once you have done so, you need to go through each of the projects in dependency order, get the Compilation for the project and call Emit on it.
You can get the compilations in dependency order with code like below. (Yes, I know that having to cast to IHaveWorkspaceServices sucks. It'll be better in the next public release, I promise).
using Roslyn.Services;
using Roslyn.Services.Host;
using System;
using System.Collections.Generic;
using System.IO;
class Program
{
static void Main(string[] args)
{
var solution = Solution.Create(SolutionId.CreateNewId()).AddCSharpProject("Foo", "Foo").Solution;
var workspaceServices = (IHaveWorkspaceServices)solution;
var projectDependencyService = workspaceServices.WorkspaceServices.GetService<IProjectDependencyService>();
var assemblies = new List<Stream>();
foreach (var projectId in projectDependencyService.GetDependencyGraph(solution).GetTopologicallySortedProjects())
{
using (var stream = new MemoryStream())
{
solution.GetProject(projectId).GetCompilation().Emit(stream);
assemblies.Add(stream);
}
}
}
}
Note1: LoadSolution still does use msbuild under the covers to parse the .csproj files and determine the files/references/compiler options.
Note2: As Roslyn is not yet language complete, there will likely be projects that don't compile successfully when you attempt this.
I also wanted to compile a full solution on the fly. Building from Kevin Pilch-Bisson's answer and Josh E's comment, I wrote code to compile itself and write it to files.
Software Used
Visual Studio Community 2015 Update 1
Microsoft.CodeAnalysis v1.1.0.0 (Installed using Package Manager Console with command Install-Package Microsoft.CodeAnalysis).
Code
using System;
using System.Collections.Generic;
using System.IO;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.Emit;
using Microsoft.CodeAnalysis.MSBuild;
namespace Roslyn.TryItOut
{
class Program
{
static void Main(string[] args)
{
string solutionUrl = "C:\\Dev\\Roslyn.TryItOut\\Roslyn.TryItOut.sln";
string outputDir = "C:\\Dev\\Roslyn.TryItOut\\output";
if (!Directory.Exists(outputDir))
{
Directory.CreateDirectory(outputDir);
}
bool success = CompileSolution(solutionUrl, outputDir);
if (success)
{
Console.WriteLine("Compilation completed successfully.");
Console.WriteLine("Output directory:");
Console.WriteLine(outputDir);
}
else
{
Console.WriteLine("Compilation failed.");
}
Console.WriteLine("Press the any key to exit.");
Console.ReadKey();
}
private static bool CompileSolution(string solutionUrl, string outputDir)
{
bool success = true;
MSBuildWorkspace workspace = MSBuildWorkspace.Create();
Solution solution = workspace.OpenSolutionAsync(solutionUrl).Result;
ProjectDependencyGraph projectGraph = solution.GetProjectDependencyGraph();
Dictionary<string, Stream> assemblies = new Dictionary<string, Stream>();
foreach (ProjectId projectId in projectGraph.GetTopologicallySortedProjects())
{
Compilation projectCompilation = solution.GetProject(projectId).GetCompilationAsync().Result;
if (null != projectCompilation && !string.IsNullOrEmpty(projectCompilation.AssemblyName))
{
using (var stream = new MemoryStream())
{
EmitResult result = projectCompilation.Emit(stream);
if (result.Success)
{
string fileName = string.Format("{0}.dll", projectCompilation.AssemblyName);
using (FileStream file = File.Create(outputDir + '\\' + fileName))
{
stream.Seek(0, SeekOrigin.Begin);
stream.CopyTo(file);
}
}
else
{
success = false;
}
}
}
else
{
success = false;
}
}
return success;
}
}
}
How can I modify an application from Console Application Type to Windows Application Type and vice versa with Mono.Cecil?
To convert a console .exe to windows .exe, you can use:
var file = "foo.exe";
var module = ModuleDefinition.ReadModule (file);
// module.Kind was previously ModuleKind.Console
module.Kind = ModuleKind.Windows;
module.Write (file);
The other way around is as simple as choosing the appropriate ModuleKind value. From Cecil's source:
public enum ModuleKind {
Dll,
Console,
Windows,
NetModule,
}
For people who needed more help on this like me :)
you may need the apt pacakge libmono-cecil-cil-dev
//mono-cecil-set-modulekind-windows.cs
using System;
using Mono.Cecil;
namespace CecilUtilsApp {
class CecilUtils {
static void Main(string[] args) {
var file = args[0];
var module = ModuleDefinition.ReadModule (file);
module.Kind = ModuleKind.Windows;
module.Write (file);
}
}
}
// -----
//Makefile
//mono-cecil-set-modulekind-eq-windows.exe:
// mcs $(shell pkg-config --libs mono-cecil) ./mono-cecil-set-modulekind-windows.cs
./mono-cecil-set-modulekind-windows.exe myprog.exe
I have a WPF C# application that contains a button.
The code of the button click is written in separate text file which will be placed in the applications runtime directory.
I want to execute that code placed in the text file on the click of the button.
Any idea how to do this?
Code sample for executing compiled on fly class method:
using System;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;
using System.IO;
using System.Reflection;
using System.Net;
using Microsoft.CSharp;
using System.CodeDom.Compiler;
namespace ConsoleApplication2
{
class Program
{
static void Main(string[] args)
{
string source =
#"
namespace Foo
{
public class Bar
{
public void SayHello()
{
System.Console.WriteLine(""Hello World"");
}
}
}
";
Dictionary<string, string> providerOptions = new Dictionary<string, string>
{
{"CompilerVersion", "v3.5"}
};
CSharpCodeProvider provider = new CSharpCodeProvider(providerOptions);
CompilerParameters compilerParams = new CompilerParameters
{GenerateInMemory = true,
GenerateExecutable = false};
CompilerResults results = provider.CompileAssemblyFromSource(compilerParams, source);
if (results.Errors.Count != 0)
throw new Exception("Mission failed!");
object o = results.CompiledAssembly.CreateInstance("Foo.Bar");
MethodInfo mi = o.GetType().GetMethod("SayHello");
mi.Invoke(o, null);
}
}
}
You can use Microsoft.CSharp.CSharpCodeProvider to compile code on-the-fly. In particular, see CompileAssemblyFromFile.
I recommend having a look at Microsoft Roslyn, and specifically its ScriptEngine class.
Here are a few good examples to start with:
Introduction to the Roslyn Scripting API
Using Roslyn ScriptEngine for a ValueConverter to process user input.
Usage example:
var session = Session.Create();
var engine = new ScriptEngine();
engine.Execute("using System;", session);
engine.Execute("double Sin(double d) { return Math.Sin(d); }", session);
engine.Execute("MessageBox.Show(Sin(1.0));", session);
Looks like someone created a library for this called C# Eval.
EDIT: Updated link to point to Archive.org as it seems like the original site is dead.
What you need is a CSharpCodeProvider Class
There are several samples to understand how does it work.
1 http://www.codeproject.com/Articles/12499/Run-Time-Code-Generation-I-Compile-C-Code-using-Mi
The important point of this example that you can do all things on flay in fact.
myCompilerParameters.GenerateExecutable = false;
myCompilerParameters.GenerateInMemory = false;
2 http://www.codeproject.com/Articles/10324/Compiling-code-during-runtime
This example is good coz you can create dll file and so it can be shared between other applications.
Basically you can search for http://www.codeproject.com/search.aspx?q=csharpcodeprovider&x=0&y=0&sbo=kw&pgnum=6 and get more useful links.