我想知道在密碼文本輸入框，按下Caps lock鍵，我想要監聽到這個事件，做出回應，而不是單純的檢測Caps lock的狀態，Caps lock鍵對應的ASC2碼是20，可是當鍵盤按下時卻監聽不到，結果沒有回應，假設我監聽其他鍵按下時卻可以，請問這是為什么呀，是因為有些鍵不能直接獲取對應的ASC整型碼嗎？請大神指點該怎么做
uj5u.com熱心網友回復：
用KeyDown判斷KeyCode
if (e.KeyCode== Keys.CapsLock)
{
}
uj5u.com熱心網友回復：
e.KeyValueuj5u.com熱心網友回復：
剛剛試了一下，KeyDown可以，為什么KeyPress不行，好奇怪
uj5u.com熱心網友回復：
keydown是按下一個按鍵，比如大小寫，小鍵盤鎖等keypress是鍵入一個字符，比如字母鍵，數字鍵
Capslock是屬于第一種，不會鍵入字符的，所以keypress不行
uj5u.com熱心網友回復：
用 KeyDown 。。。uj5u.com熱心網友回復：
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Windows.Forms;
namespace Test_7
{
public class KeyRecord
{
public List<string> _Record = new List<string>();
public RichTextBox r1 = new RichTextBox() { Size = new Size(400, 300) };
private const int WM_KEYDOWN = 0x100;
private const int WM_KEYUP = 0x101;
private const int WM_SYSKEYDOWN = 0x104;
private const int WM_SYSKEYUP = 0x105;
public event KeyEventHandler OnKeyDownEvent;
public event KeyEventHandler OnKeyUpEvent;
public event KeyPressEventHandler OnKeyPressEvent;
static int hKeyboardHook = 0;
public const int WH_KEYBOARD_LL = 13;
HookProc KeyboardHookProcedure;
[StructLayout(LayoutKind.Sequential)]
public class KeyboardHookStruct
{
public int vkCode;
public int scanCode;
public int flags;
public int time;
public int dwExtraInfo;
}
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
public static extern bool UnhookWindowsHookEx(int idHook);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
public static extern int CallNextHookEx(int idHook, int nCode, Int32 wParam, IntPtr lParam);
[DllImport("user32")]
public static extern int GetKeyboardState(byte[] pbKeyState);
public delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam);
public KeyRecord()
{
this.OnKeyPressEvent += new KeyPressEventHandler(KeyBordHook_OnKeyPressEvent);
Start();
}
public void Start()
{
if (hKeyboardHook == 0)
{
KeyboardHookProcedure = new HookProc(KeyboardHookProc);
Module m = Assembly.GetExecutingAssembly().GetModules()[0];
IntPtr itp = Marshal.GetHINSTANCE(m);
hKeyboardHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardHookProcedure, itp, 0);
if (hKeyboardHook == 0) Stop();
}
}
public void Stop()
{
bool retKeyboard = true;
if (hKeyboardHook != 0)
{
retKeyboard = UnhookWindowsHookEx(hKeyboardHook);
hKeyboardHook = 0;
}
}
private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
{
if ((nCode >= 0) && (OnKeyDownEvent != null || OnKeyUpEvent != null || OnKeyPressEvent != null))
{
KeyboardHookStruct MyKeyboardHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));
if (OnKeyPressEvent != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN))
{
r1.AppendText("KeyCode:" + MyKeyboardHookStruct.vkCode + "| Time:" + DateTime.Now + "\r");
}
}
return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);
}
private void KeyBordHook_OnKeyPressEvent(object sender, KeyPressEventArgs e) { }
}
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
KeyRecord kr = new KeyRecord();
kr.r1.Location = new Point(10, 10);
this.Controls.Add(kr.r1);
kr.Start();
}
}
}
uj5u.com熱心網友回復：
也可以試試keyup轉載請註明出處，本文鏈接：https://www.uj5u.com/net/63501.html
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