未从 try-catch 块内部捕获“未处理”异常

Question

I am attempting to run an async output that will last a large amount of time, and then closing the application during execution which causes the textbox to dispose. I thought this would be handled by simply returning in a try-catch statement, but VS still says there is an "unhandled" exception. Here is the code:

public void AppendOutput(string text)
    {
        var timeNow = DateTime.Now;

        if ((DateTime.Now - previousTime).Milliseconds <= 50) return;
        try
        {
            synchronizationContext.Post(new SendOrPostCallback(o =>
            {
                Output.AppendText((string)o);
            }), text);
        }
        catch(ObjectDisposedException e)
        {
            return;
        }

        previousTime = timeNow;
    }

Here is what happens in debug:

I there a reason why this is considered unhandled? I thought that's what try-catch was for. My understanding was that I could simply return because there's no need to handle exceptions for a program that is attempting to write to a textbox that has been disposed; the program should be ending the thread on its own. What is the correct way to deal with this problem?

Answer 1

According to your description, you want to solve the abnormal problem that occurs during debugging.

You can add the following code in the initialization component function, as shown below:

public Form1()
        {
            InitializeComponent();
            Control.CheckForIllegalCrossThreadCalls = false;
        }

Result: