Manage C # ScrollBar in Visual Studio

Question

I require that when the textbox text changes programmatically, the scrollbar does not move to the very top. At least how to set its coordinate programmatically and return the current position. How the TextBox property works, AutoScrollOffset is not at all clear.

My TextBox is a long list of time-varying values without user input in the form of a long vertical bar. and I would like to move the scroll for example to the middle of the list and so that it remains there.

Very interesting question. Waiting for an answer. PS And why in the question tags "with"? - Jakeroid

Accepted Answer · 2011-05-09T15:43:12

To control the ScrollBar, you can use API functions:

//типы ScrollBar-ов private const int SB_HORZ = 0x0; private const int SB_VERT = 0x1; //WM - сообщения private const int WM_HSCROLL = 0x114; private const int WM_VSCROLL = 0x115; //Комманды для ScrollBar-а private const int SB_THUMBPOSITION = 4; //Получении позиции //Возвращает насколько я понял верхнюю видимую строку TextBox-а //nBar = тип ScrollBar [DllImport("user32.dll")] private static extern int GetScrollPos(IntPtr hWnd, int nBar); //Установка позиции бегунка на ScrollBar-е //nBar = тип ScrollBar //nPos = строка [DllImport("user32.dll")] private static extern int SetScrollPos(IntPtr hWnd, int nBar, int nPos, bool bRedraw); //PostMessage, необходима для установки позиции в TextBox-е [DllImport("user32.dll")] private static extern bool PostMessageA(IntPtr hWnd, int nBar, int wParam, int lParam); //Пример private void test() { //Получаем актуальную позицию ScrollBar-а TextBox-а int originalLine = GetScrollPos(textBox1.Handle, SB_VERT); //Ставим бегунок ScrollBar-a, будто верхняя видимая строка у нас восьмая SetScrollPos(textBox1.Handle, SB_VERT, 8, true); //Прокручиваем TextBox к восьмой строке PostMessageA(textBox1.Handle, WM_VSCROLL, SB_THUMBPOSITION + 0x10000 * 8, 0); }

Documentation:

yapycoder yapycoder 1,734 11 silver marks 16 bronze marks · Answer 2 · 2011-05-08T13:44:52

If you change not Text , but SelectedText , then it will scroll to the place of change. For example, you can add text and scroll to the end:

 textBox1.SelectionStart = textBox1.Text.Length; textBox1.SelectionLength = 0; textBox1.SelectedText += "ahaha haha";

it doesn’t fit, since I have a textbox for viewing, not editable, and I don’t want to place the cursor at all, so that I can scroll to the desired value and see how it changes over time.

Manage C # ScrollBar in Visual Studio

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