[c#] Use of Application.DoEvents()

The DoEvents does allow the user to click around or type and trigger other events, and background threads are a better approach.

However, there are still cases where you may run into issues that require flushing event messages. I ran into a problem where the RichTextBox control was ignoring the ScrollToCaret() method when the control had messages in queue to process.

The following code blocks all user input while executing DoEvents:

using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace Integrative.Desktop.Common
{
    static class NativeMethods
    {
        #region Block input

        [DllImport("user32.dll", EntryPoint = "BlockInput")]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool BlockInput([MarshalAs(UnmanagedType.Bool)] bool fBlockIt);

        public static void HoldUser()
        {
            BlockInput(true);
        }

        public static void ReleaseUser()
        {
            BlockInput(false);
        }

        public static void DoEventsBlockingInput()
        {
            HoldUser();
            Application.DoEvents();
            ReleaseUser();
        }

        #endregion
    }
}