C#/VB.NET Winform程序自定义输入光标

[DllImport("user32.dll")]
static extern bool CreateCaret(IntPtr hWnd, IntPtr hBitmap, int nWidth, int nHeight);
[DllImport("user32.dll")]
static extern bool ShowCaret(IntPtr hWnd);
[DllImport("User32.dll")]
static extern bool HideCaret(IntPtr hWnd);
[DllImport("User32.dll")]
static extern bool SetCaretPos(int x, int y);
[DllImport("user32.dll")]
static extern bool DestroyCaret();

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace CustomCaret
{
    /// <summary>
    /// 自定义输入光标的演示
    /// 作者： 三角猫
    /// 网址： http://www.zu14.cn/
    /// 转载请保留此信息
    /// </summary>
    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);
        [DllImport("User32.dll")]
        static extern bool HideCaret(IntPtr hWnd);
        [DllImport("User32.dll")]
        static extern bool SetCaretPos(int x, int y);
        [DllImport("user32.dll")]
        static extern bool DestroyCaret();

        public Form1()
        {
            InitializeComponent();
            //为输入框绑定光标变化的处理事件
             this.textBox2.GotFocus += new EventHandler(textBox2_GotFocus);
            this.textBox2.LostFocus += new EventHandler(textBox2_LostFocus);
        }

        void textBox2_LostFocus(object sender, EventArgs e)
        {
            HideCaret(this.textBox2.Handle);
            DestroyCaret();
        }

        void textBox2_GotFocus(object sender, EventArgs e)
        {
            CreateCaret(textBox2.Handle, IntPtr.Zero, 10, textBox2.Height);
            ShowCaret(textBox2.Handle);
        }
    }
}