using System;
using System.Windows.Forms;
using System.Runtime.InteropServices;namespace WindowsApplication1
{
public partial class Form1 : Form
{
[DllImport("user32.dll")]
static extern bool CreateCaret(IntPtr hWnd, IntPtr hBitmap, int nWidth, int nHeight);
[DllImport(
"user32.dll")]
static extern bool ShowCaret(IntPtr hWnd);public Form1()
{
InitializeComponent();
richTextBox1.GotFocus += new EventHandler(richTextBox1_GotFocus);
}private void richTextBox1_GotFocus(object sender, EventArgs e)
{
this.BeginInvoke(new MethodInvoker(ChangeCaret));
}private void richTextBox1_SelectionChanged(object sender, EventArgs e)
{
this.ChangeCaret();
}private void richTextBox1_MouseDown(object sender, MouseEventArgs e)
{
this.ChangeCaret();
}private void ChangeCaret()
{
CreateCaret(this.richTextBox1.Handle, IntPtr.Zero, 10, 15);
ShowCaret(this.richTextBox1.Handle);
}private void richTextBox1_KeyUp(object sender, KeyEventArgs e)
{
this.ChangeCaret();
}
}
}
