使用BeginInvoke禁用表单控件

Question

I'm using the following code to disable form controls while i'm doing some longTask() thread. But the controls are not getting disabled.. Here is my code for disable() method.

    public void disableFormControls()
    {
        if (InvokeRequired)
        {
            this.BeginInvoke(new Action(disableFormControls));
            return;
        }
        groupBoxInput.Enabled = false;
        groupBoxOutput.Enabled = false;
        btnGen.Enabled = false;
        btnReset.Enabled = false;
    }

Here is how i'm calling it.. NOTE: LongTask() will be running in a separate thread.

    private void LongTask()
    {
        disableFormControls();
        Console.WriteLine("Started Records::" + DateTime.Now);
        //Doing my long tasks here 
        enableFormControls();
    }

Can you please let me know where i'm wrong..

Answer 1

Try this, I changed the Invoke of enableForm to instead call disableFormControls . Also I did this synchronously instead of asynchronously so your background thread isn't doing anything until the UI is updated properly. I'm also assuming disableFormControls is a method on your Form.

public void disableFormControls()
{
    if (InvokeRequired)
    {
        this.Invoke(new Action(disableFormControls));
        return;
    }
    groupBoxInput.Enabled = false;
    groupBoxOutput.Enabled = false;
    btnGen.Enabled = false;
    btnReset.Enabled = false;
}

Answer 2

为确保在UI线程上同步执行代码，请使用Invoke而不是BeginInvoke 。

Answer 3

You have two choices here as you can cannot modify winform UI controls from non UI thread

1. You can move the enable/disable UI code back to the UI thread. Before starting the task disable the controls in the UI thread and use the dispatcher to enable them back in the UI thread at task completion.

2. You can use data binding to bind the enable state of these controls to some no UI object that you can freely modify from any thread.