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Pass function as parameter C# (Timer.Enable)

i'm learning c# and i'm trying some stuff with the System.Timers.Timer, and i'm having a problem, cause i want to make a function that receives another function so i could 'bind' it to the timer.Elapsed event. I'm trying to build something like:
public void timerElapsedMethod(my method)
{
timer.Elapsed += my method;
}
There is a way where i can do that ?
edit 1:
Guys, what i'm trying to do is, baiscally encapsulate the timer class, so i want a user to call my function passing his function as an argument.
Like:
class MyTimer
{
public static Timer timer;
public MyTimer()
{
timer = new Timer();
}
internal void *timerElapsedMeth*(Action<object, ElapsedEventArgs> method)
{
timer.Elapsed += (if i put method here i get an error);
}
}
Now imagine someone wants to use my class and wanna do something like:
class SomeUserRandomClass
{
public static MyTimer mytimer;
public SomeUserRandomClass()
{
mytimer = new MyTimer();
}
public void userRandomMethod()
{
some code...
}
myTimer.*timerElapsedMeth*(userRandomMethod);
}
Is it possible to do that ?
Thx

You can do it something like the following.
I wouldn't try to try and asign it to the event directly. But hide the event details
class MyTimer
{
private readonly Action _userAction;
private Timer timer;
public MyTimer(Action userAction)
{
_userAction = userAction;
timer = new Timer();
timer.Elapsed += Timer_Elapsed;
}
private void Timer_Elapsed(object sender, ElapsedEventArgs e)
{
_userAction?.Invoke();
}
}

You can accomplish this using lambda expressions.
public void timerElapsedMethod(Action myMethod) {
var timer =new Timer();
timer.Elapsed += (s, e) => {
myMethod?.Invoke();
};
}
if myMethod needs parameters, you can edit the timerElapsedMethod to take parameters.
public void timerElapsedMethod(Action myMethod, int param) {
var timer =new Timer();
timer.Elapsed += (s, e) => {
myMethod?.Invoke(param);
};
}
Hope this can help.

Create an event in your wrapper class which is fired when the timer event is fired.
class MyTimer
{
// Is there a reason you want this timer to be public? Otherwise make it private.
public static Timer timer;
public event EventHandler<ElapsedEventArgs> OnTimerEvent;
public MyTimer()
{
timer = new Timer();
}
private static void OnTimedEvent(Object sender, ElapsedEventArgs e)
{
OnTimerEvent?.Invoke(this, e);
}
}
Using your timer class:
class SomeUserRandomClass
{
private static MyTimer mytimer;
public SomeUserRandomClass()
{
mytimer = new MyTimer();
myTimer += TimerEventHandler; // Register to the event
}
public void userRandomMethod()
{
some code...
}
private static void TimerEventHandler(Object sender, ElapsedEventArgs e)
{
// Handle the event
}
}
Make sure to "unregister" the event when you Dispose your SomeUserRandomClass:
myTimer -= TimerEventHandler;

Passing a variable as a parameter to a class and changing that value of that variable in method within that class

forgive me if there's any typos i wrote this by hand.. i was just wondering if there's anyway i can pass a parameter to a class and change it's variable within a method of that variable.
i was thinking of passing by reference but i can't pass the variable through the Elapsed method property.. any suggestions?
public partial class MainWindow : Window
{
private CustomTimerClass _customTimer;
private int _varIWantToChange;
public MainWindow()
{
_varIWantToChange = 1;
_customTimer = new CustomTimerClass(_varIWantToChange);
}
...
}
public CustomTimerClass()
{
private System.Timers.Timer _timer;
public CustomTimerClass(int varIWantToChange)
{
_timer = new Timer();
...
_timer.Elapsed += _timer_Elapsed; //i can't pass varIwantToChange as a parameter here
}
public void _timer_Elapsed(object sender, ElapsedEventArgs e)
{
//i want to be able to change the value of the variable "_varIWantToChange" here
}
}

You could easily pass in a callback method:
class Program
{
static private CustomTimerClass _customTimer;
static private int _varIWantToChange = 1;
static public void Main()
{
_customTimer = new CustomTimerClass(changeVar);
while (_varIWantToChange == 1)
{
System.Threading.Thread.Sleep(1);
}
}
static public void changeVar(object sender, ElapsedEventArgs e)
{
_varIWantToChange++;
Console.WriteLine(_varIWantToChange);
}
}
public class CustomTimerClass
{
private System.Timers.Timer _timer;
public CustomTimerClass()
{
}
public CustomTimerClass(ElapsedEventHandler callbackMethod)
{
_timer = new Timer();
_timer.Elapsed += callbackMethod; //i can't pass varIwantToChange as a parameter here
_timer.Elapsed += _timer_Elapsed;
_timer.Interval = 500;
_timer.Start();
}
public void _timer_Elapsed(object sender, ElapsedEventArgs e)
{
// Do timer stuff
}
}

create a public int property
make your property set _varIWantToChange and get _varIWantToChange if you need it

Any reason you are not using System.Threading.Timer instead of System.Timers.Timer? The Threading version has constructors that allow you to pass an object in the constructor that is then passed to the handler as an argument.
From MSDN: http://msdn.microsoft.com/en-us/library/system.threading.timer.aspx

c# Function work with Timer(AutoFunction)

I do have one checking function that will run once opening the application.
How to make it Auto Function like every 20 seconds run the function?
Main()
{
Checking();
}
public void Checking() // run this function every 20 seconds
{ // some code here
}

You can use the C# Timer class
public void Main()
{
var myTimer = new Timer(20000);
myTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
myTimer.Enabled = true;
Console.ReadLine();
}
private static void OnTimedEvent(object source, ElapsedEventArgs e)
{
Console.WriteLine("The Elapsed event was raised at {0}", e.SignalTime);
}

Main()
{
Timer tm = new Timer();
tm.Interval = 20000;//Milliseconds
tm.Tick += new EventHandler(tm_Tick);
tm.Start();
}
void tm_Tick(object sender, EventArgs e)
{
Checking();
}
public void Checking()
{
// Your code
}

Elapsed event for the time not working, c#

I am using a timer to output text to textbox every 2 seconds. but it seems that it doesnt work. any idea what is wrong. here is my code:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public static System.Timers.Timer aTimer;
public void BtnGenData_Click(object sender, EventArgs e)
{
aTimer = new System.Timers.Timer(10000);
// Hook up the Elapsed event for the timer.
aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
// Set the Interval to 2 seconds (2000 milliseconds).
aTimer.Interval = 2000;
aTimer.Enabled = true;
}
public static void OnTimedEvent(object source, ElapsedEventArgs e)
{
string GenData = "Welcome";
Form1 frm1 = new Form1();
frm1.TboxData.AppendText(GenData.ToString());
}
}
Actually i dont see any output coming.

Although this is not straightly connected with the problem you have in your code, but...
From MSDN System.Timers.Timer:
The server-based Timer is designed for use with worker threads in a
multithreaded environment.
In Windows Forms you can use System.WindowsForms.Timer:
System.Windows.Forms.Timer timer;
public Form1()
{
InitializeComponent();
timer = new Timer();
timer.Interval = 1000;
timer.Tick += new EventHandler(timer_Tick);
}
public void BtnGenData_Click(object sender, EventArgs e)
{
BtnGenData.Enabled = false;
timer.Start();
}
void timer_Tick(object sender, EventArgs e)
{
timer.Stop();
BtnGenData.Enabled = true;
//do what you need
}
As for your code, why make the timer static? Try to use this:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public System.Timers.Timer aTimer;
public void BtnGenData_Click(object sender, EventArgs e)
{
aTimer = new System.Timers.Timer(10000);
aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
aTimer.Interval = 2000;
aTimer.Enabled = true;
}
public void OnTimedEvent(object source, ElapsedEventArgs e)
{
this.TboxData.AppendText("Welcome");
}
}
Also you should take into consideration, what could happen if you pressed the button twice...

The problem is in this method:
public static void OnTimedEvent(object source, ElapsedEventArgs e)
{
string GenData = "Welcome";
Form1 frm1 = new Form1();
frm1.TboxData.AppendText(GenData.ToString());
}
By calling new Form1(); you create a new form. This form is created as hidden, you change the text, but it is not displayed and at the end of this method it is garbage collected. What you want is to reuse your existing one. Completely remove this line and use your existing form. By default the name should be form1
public static void OnTimedEvent(object source, ElapsedEventArgs e)
{
string GenData = "Welcome";
form1.TboxData.AppendText(GenData.ToString());
}

System.Timers.Timer Elapsed Exception handling in Library

I would like handle the occurred System.Timers.Timer elapsed exception (in my DLL library) within my WPF application. But I'm not be able to do that. It throws in my DLL library and the application will crashing...
Does anybody know how I can solve the problem?
Here my code:
public partial class MainWindow : Window
{
MyClass _myClassInstance = null;
public MainWindow()
{
InitializeComponent();
try
{
_myClassInstance = new MyClass();
}
catch(Exception ex)
{
//Here i would like to receive the exception
//But it never goes in there
MessageBox.Show(ex.Message);
}
}
}
public class MyClass
{
private System.Timers.Timer _timer = null;
public MyClass()
{
_timer = new Timer();
_timer.Interval = 2000; //2 Seconds
_timer.Elapsed += new ElapsedEventHandler(_timer_Elapsed);
_timer.Start();
ConnectTo();
}
void _timer_Elapsed(object sender, ElapsedEventArgs e)
{
//If timer is elapsed I have to raise an exception
throw new Exception("It's taking longer than expected. Progress cancelled!");
}
private void ConnectTo()
{
//Just an example implementation
//Do something!!
//Connect to SerialPort and wait for correct response
//If connected than
_timer.Stop();
}
}

The exception is thrown on another thread (as per your choice for Timing.Timer).
Try this inside 1 assembly: you can't catch it either. That it's in a DLL doesn't matter.
You can only solve this by re-thinking the problem and picking another solution.

The exception is happening inside the event. This is run on another thread, therefore it's never going to make it back to your original thread.
Two possibilities to do this differently.
Your serial port com library has some sort of timeout functionality (maybe), just use it instead.
Do your serial port checking on a separate tread. If your time runs out, kill that thread.
public class MyClass
{
private System.Timers.Timer _timer = null;
private Thread t;
public MyClass()
{
_timer = new Timer();
_timer.Interval = 2000; //2 Seconds
_timer.Elapsed += new ElapsedEventHandler(_timer_Elapsed);
_timer.Start();
t = new Thread(new ThreadStart(ConnectTo));
t.Start();
t.Join();
}
void _timer_Elapsed(object sender, ElapsedEventArgs e)
{
//If timer is elapsed I have to raise an exception
if (t != null)
t.Abort();
}
private void ConnectTo()
{
//Just an example implementation
//Do something!!
//Connect to SerialPort and wait for correct response
//If connected than
_timer.Stop();
}
}

As an alternative approach, rather trying to control your application flow with Exceptions, you could use events instead e.g.
public partial class MainWindow : Window
{
MyClass _myClassInstance = null;
public MainWindow()
{
InitializeComponent();
_myClassInstance = new MyClass();
_myClassInstance.TimedOut += delegate (object sender, EventArgs e) {
((MyClass)sender).CancelConnect();
MessageBox.Show("Timeout!");
};
_myClassInstance.ConnectTo();
}
}
...
public class MyClass
{
Timer _timer = new Timer();
public event EventHandler TimedOut;
void _timer_Elapsed(object sender, ElapsedEventArgs e)
{
OnTimedOut();
}
private void OnTimedOut()
{
var handler = TimedOut;
if (handler != null)
{
handler(this, EventArgs.Empty);
}
}
public void ConnectTo(int timeout = 2000)
{
CancelConnect();
_timer.Interval = timeout; // pass timeout in so it's flexible
_timer.Elapsed += new ElapsedEventHandler(_timer_Elapsed);
_timer.Start();
// do connect stuff...
_timer.Stop();
}
public void CancelConnect()
{
_timer.Stop();
// cancel connect stuff...
}
}
I think you had far too much going on in your constructor for MyClass so I moved it into ConnectTo which you invoke directly from your MainWindow.

Not work:
MessageBox.Show(e.Message); doen's throw
public class MyClass
{
private System.Timers.Timer _timer = null;
private Thread t;
public MyClass()
{
try
{
_timer = new System.Timers.Timer();
_timer.Interval = 5000; //2 Seconds
_timer.Elapsed += new ElapsedEventHandler(_timer_Elapsed);
_timer.Start();
t = new Thread(new ThreadStart(ConnectTo));
t.Start();
t.Join();
}
catch (Exception e)
{
MessageBox.Show(e.Message);
}
}
void _timer_Elapsed(object sender, ElapsedEventArgs e)
{
//If timer is elapsed I have to raise an exception
if (t != null)
{
t.Abort();
}
}
private void ConnectTo()
{
//Just an example implementation
//Do something!!
try
{
//Connect to SerialPort and wait for correct response
using (SqlConnection _SC = new SqlConnection("aaaa"))
{
_SC.Open();
}
}
catch (Exception)
{
throw;
}
finally
{
//If connected than
_timer.Stop();
}
}
}