I believe am in need of creating custom RichTextBox in C#. One kind of like that:
I admit it might not even have to be RichTextBox, but after some research I decided it's gonna be the easiest way. Functionality I need are icons at each row, checkboxes and text formatting. My program will process each line of the text and mark lines that are correct, incorrect, and strike out lines not necessary in further work, while showing line that's currently processed and allowing user to edit some lines freely (here: lines before Around 3 000 won't be editable, but those under the line will).
What's the problem then? I have no idea how to get it done. I've seen tutorial on how to make single-line textBox with icon or checkbox nearby, but I have no idea how to make both, and for multiline textBox (so I could freely scroll and everything would work fluently). I've read some questions on SO as well, but neither helped me.
I just don't know how to get started, I realize it won't be 5 min work, but I'm willing to do it. Until now I've been only able to create custom control deriving from RichTextBox, but I have no idea which methods and how to override. Any help appreciated.
Try to use WebBrowser control instead RichTextBox.
You can add CheckBoxes and editable content by setting a correct HTML code to it.
Set each TextBox or CheckBoxes ids and use GetElementsByTagName or GetElementById to access inner elements to get or set its attributes or values.
来源：https://stackoverflow.com/questions/12364527/creating-custom-richtextbox-control