I have a class
Public class DDSModel
{
public string message {get; set;}
}
I'm using this class in c# code
but I want to hold my code execution till the message property is empty.
I have a different method that is filling the property after some time it depends on user it can be filled in 2 seconds or 2 minutes. But as soon as the user fills the message I need to execute where it was hold.
I can use while in this but I just want to use the TaskCompletionSource.
Let's break down your problem. You want to watch the value of DDSModel.message, and wait until the value has a value of null, then react to it, all using Task.
DDSModel.messageDo
public class DDSModel : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged([CallerMemberName] string property)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
private string _message;
public string Message
{
get { return _message; }
set { _message = value; OnPropertyChanged(); }
}
}
Then you can do:
public Task WaitUntilMessageIsNull(model DDSModel)
{
var tcs = new TaskCompletionSource<int>();
PropertyChangedEventHandler handler = (o, e) => {
if(model.Message == null && e.PropertyName == "Message")
{
tcs.SetResult(0);
model.PropertyChanged -= handler;
}
}
model.PropertyChanged += handler;
return tcs.Task;
}
However if you want cleaner code, I would recommend using System.Reactive for the logic.
public Task WaitUntilMessageIsNull(model DDSModel)
{
return Observable
.FromEventPattern<PropertyChangedEventHandler, PropertyChangedEventArgs>(
h => model.propertyChanged += h,
h => model.propertyChanged -= h)
.Where(x => x.EventArgs.PropertyName == "Message")
.Where(_ => model.Message == null)
.ToTask();
}
u can use C# - Multithreading property to hold the execution
visit here to know how:https://www.tutorialspoint.com/csharp/csharp_multithreading.htm
