我编写了代码以在单独的页面中显示文本,例如 Microsoft Word,我使用一组文本框,当用户填写一个文本框时,会自动显示新框,并且光标会移动到她身上。
问题是当用户在文本框中写入最后一行时,该框会向下滚动一点,正如您将在何时运行此代码时看到的那样,我该如何禁用滚动。
编码 :
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
List<myRTB> pages; // collection of our RichTextBox, use as pages
public Form1()
{
InitializeComponent();
pages = new List<myRTB>();
pages.Add(new myRTB());
pages[0].Width = 200;
pages[0].Height = 290;
pages[0].Location = new Point(50, 10);
pages[0].Name = "0";
this.Controls.Add(pages[0]);
this.Width = 300;
this.Height = 360;
this.AutoScroll = true;
}
public void AddPage(int correntPageIndex)
{
if (correntPageIndex == (pages.Count - 1))
{
// create a new page
pages.Add(new myRTB());
pages[correntPageIndex + 1].Width = 200;
pages[correntPageIndex + 1].Height = 290;
pages[correntPageIndex + 1].Location = new Point(50, pages[correntPageIndex].Location.Y + 300);
this.Controls.Add(pages[pages.Count - 1]);
this.Name = (correntPageIndex + 1).ToString();
}
bool CursorInEnd = (pages[correntPageIndex].SelectionStart == pages[correntPageIndex].TextLength);
// Transfer the last word on the previous page, to the new page
int lastLineIndex = pages[correntPageIndex].GetLineFromCharIndex(pages[correntPageIndex].TextLength - 2);
// find the index of the first char in the last line
int indexOfFirstCharInLastLine = pages[correntPageIndex].GetFirstCharIndexFromLine(lastLineIndex);
// find the index of the last space in the last line
int indexOfLastSpace = pages[correntPageIndex].Text.LastIndexOf(' ', indexOfFirstCharInLastLine);
string restOfString;
if (indexOfLastSpace < 0) // no spaces in the last line
{
restOfString = pages[correntPageIndex].Text.Substring(pages[correntPageIndex].TextLength - 1);
pages[correntPageIndex + 1].Text.Insert(0, restOfString);
pages[correntPageIndex].Text.Remove(pages[correntPageIndex].TextLength - 1);
}
else // there is spaces in the last line
{
restOfString = pages[correntPageIndex].Text.Substring(indexOfLastSpace + 1);
pages[correntPageIndex + 1].Text = pages[correntPageIndex + 1].Text.Insert(0, restOfString);
pages[correntPageIndex].Text = pages[correntPageIndex].Text.Remove(indexOfLastSpace + 1);
}
if (CursorInEnd)
{
// Move the cursor to next page
pages[correntPageIndex + 1].SelectionStart = restOfString.Length;
pages[correntPageIndex + 1].Focus();
}
}
}
class myRTB : RichTextBox
{
public myRTB()
{
this.ScrollBars = RichTextBoxScrollBars.None;
}
protected override void WndProc(ref Message m)
{
// catch the request resize message
if (m.Msg == (WM_REFLECT | WM_NOTIFY))
{
REQRESIZE rrs = (REQRESIZE)(Marshal.PtrToStructure(m.LParam, typeof(REQRESIZE)));
if (rrs.nmhdr.code == EN_REQUESTRESIZE)
{
if (rrs.rc.ToRectangle().Height > this.ClientRectangle.Height)
{
((Form1)Parent).AddPage(int.Parse(this.Name));
}
}
}
base.WndProc(ref m);
}
[StructLayout(LayoutKind.Sequential)]
public struct NMHDR
{
public IntPtr HWND;
public uint idFrom;
public int code;
public override String ToString()
{
return String.Format("Hwnd: {0}, ControlID: {1}, Code: {2}",
HWND, idFrom, code);
}
}
[StructLayout(LayoutKind.Sequential)]
public struct REQRESIZE
{
public NMHDR nmhdr;
public RECT rc;
}
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int Left, Top, Right, Bottom;
public override string ToString()
{
return String.Format("{0}, {1}, {2}, {3}", Left, Top, Right,
Bottom);
}
public Rectangle ToRectangle()
{
return Rectangle.FromLTRB(Left, Top, Right, Bottom);
}
}
public const int WM_USER = 0x400;
public const int WM_NOTIFY = 0x4E;
public const int WM_REFLECT = WM_USER + 0x1C00;
public const int EN_REQUESTRESIZE = 0x701;
}
}