Form And Code Unsynched

I have a textbox with some text in it ("hello"). If I change the text to anything else and get the text from the textbox (through the code), I'll get "hello" although I changed it.

In another case, when I change a checkbox's check state, the checkbox won't visually tick (or untick).

Anyone has an idea what's going on and how to sync them?

I've opened a new project, thats the only function on my form :

public void Switch()
    {
        Checkbox1.Checked = !Checkbox1.Checked;
    }

and I call it from the program.cs :

开发者_如何学JAVAstatic MainForm MyForm;
MyForm = new MainForm();
MyForm.Switch();

I assume that you are simply instantiating MainForm in Main and then calling Switch.

Which means that you are not sending the request on the UI Thread.

So, you can Invoke your code to run on the UI thread:

public void Switch()
{
    // true if off of the UI thread, and thus must be Invoked
    if (this.InvokeRequired)
    {
        // off UI thread; put it onto it
        this.Invoke(Switch);
    }
    else
    {
        // on UI thread
        Checkbox1.Checked = ! Checkbox1.Checked;
    }
}

You should only interact with the UI from the UI Thread. You should not litter your code with Invokes unless you expect to call it off of the UI Thread, or you provide a means for others to do so (some public API).