Ok Found part of my solution here c# - Is ConfigurationManager.AppSettings available in .NET Core 2.0? - Stack Overflow[^] I installed System.Configuration.ConfigurationManager from Nuget into my .net core 2.2 application. I then reference using System.Configuration; Next, I changed WebConfigurationManager.AppSettings to .. ConfigurationManager.AppSettings

you can lighten text , so the text is clearer. 2) you can make two pictures (one is lighten, the other is darken) when mouse over the places , just change the pictures. 3) of course, you can draw a picture, by different way.(Pixel Zoom, different background color.....)

What that would appear true in theory, not all fonts can be rendered at all point sizes. For example, consider a Label "label1" with initial font "Microsoft Sans Serif" at point size 8.25. Font f = new Font(label1.Font.FontFamily, label1.Font.SizeInPoints + 0.5f); label1.Font = f; label1.Text = label1.Font.SizeInPoints.ToString(); Execute that code a few times (at least on my WinXP machine) via a button click or whatever, and the font's appearance at 9.25 and 9.75 are identical, as are 10.75 and 11.25, etc. Also, there is obviously some mapping going on, setting the font size to 8.0 results in 8.25, 10.0 to 9.75, etc. Is there any way of knowing, short of trial and error, if changing the point size by some amount will actually have impact on what is rendered?

In the Activate or Shown Event of the child form you could probably include code like the following: this.Location = new Point(this.ParentForm.Width - (this.Width + 10), 0); Of course, if you put the code in the Activate event you will want to ensure the code only executes the first time the form activates. That should get your MDI child in the ballpark of the right corner of the parent form. You might have to play around with the value you add to this.Width a little bit. Good luck.

You may read about custom controls at the MSDN. About : Islam About : Me