VB.net 中如何获取键盘输入的ASCii码

Private Sub Form1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles Me.KeyPress

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If Asc(0) Then

textbox1.text="0"

end if

end sub

vb.net 获取键盘输入的字符

参考方法如下，具体解释已经注解在代码中；

/定义变量

public delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam);

static int hKeyboardHook = 0;

HookProc KeyboardHookProcedure;

/*************************

* 声明API函数

* ***********************/

// 安装钩子 （using System.Runtime.InteropServices;）

[DllImport("user32.dll",CharSet=CharSet.Auto, CallingC.StdCall)]

public static extern int SetWindowsHookEx(int idHook,HookProc lpfn, IntPtr hInstance, int threadId);

// 卸载钩子

[DllImport("user32.dll",CharSet=CharSet.Auto, CallingC.StdCall)]

public static extern bool UnhookWindowsHookEx(int idHook);

// 继续下一个钩子

[DllImport("user32.dll",CharSet=CharSet.Auto, CallingC.StdCall)]

public static extern int CallNextHookEx(int idHook, int nCode, Int32 wParam, IntPtr lParam);

// 取得当前线程编号（线程钩子需要用到）

[DllImport("kernel32.dll")]

static extern int GetCurrentThreadId();

//钩子子程：就是钩子所要做的事情

private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)

{

if (nCode = 0)

{

/****************

//线程键盘钩子判断是否按下键

Keys keyData = (Keys)wParam;

if(lParam.ToInt32() 0)

{

// 键盘按下

}

if(lParam.ToInt32() 0)

{

// 键盘抬起

}

****************/

/****************

//全局键盘钩子判断是否按下键

wParam = = 0x100 // 键盘按下

wParam = = 0x101 // 键盘抬起

****************/

KeyMSG m = (KeyMSG) Marshal.PtrToStructure(lParam, typeof(KeyMSG));//键盘

// 在这里添加你想要做是事情(比如把键盘nCode记录下来,搞个邮件发送程序发到自己的邮箱去)

return 0;//如果返回1，则结束消息，这个消息到此为止，不再传递。如果返回0或调用CallNextHookEx函数则消息出了这个钩子继续往下传递，也就是传给消息真正的接受者

}

return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);

}

//键盘结构

public struct KeyMSG

{

public int vkCode; //键值

public int scanCode;

public int flags;

public int time;

public int dwExtraInfo;

}

// 安装钩子

public void HookStart()

{

if(hKeyboardHook == 0)

{

// 创建HookProc实例

KeyboardHookProcedure = new HookProc(KeyboardHookProc);

// 设置线程钩子

hKeyboardHook = SetWindowsHookEx( 13,KeyboardHookProcedure,Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly().GetModules()[0]),0);

//************************************

//键盘线程钩子

//SetWindowsHookEx( 2,KeyboardHookProcedure, IntPtr.Zero, GetCurrentThreadId()); //GetCurrentThreadId()为要监视的线程ID,你完全可以自己写个方法获取QQ的线程哦

//键盘全局钩子,需要引用空间(using System.Reflection;)

//SetWindowsHookEx( 13,KeyboardHookProcedure,Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly().GetModules()[0]),0);

//

//关于SetWindowsHookEx (int idHook, HookProc lpfn, IntPtr hInstance, int threadId)函数将钩子加入到钩子链表中，说明一下四个参数：

//idHook 钩子类型，即确定钩子监听何种消息，上面的代码中设为2，即监听键盘消息并且是线程钩子，如果是全局钩子监听键盘消息应设为13，

//线程钩子监听鼠标消息设为7，全局钩子监听鼠标消息设为14。

//

//lpfn 钩子子程的地址指针。如果dwThreadId参数为0 或是一个由别的进程创建的线程的标识，lpfn必须指向DLL中的钩子子程。 除此以外，lpfn可

//以指向当前进程的一段钩子子程代码。钩子函数的入口地址，当钩子钩到任何消息后便调用这个函数。

//

//hInstance应用程序实例的句柄。标识包含lpfn所指的子程的DLL。如果threadId 标识当前进程创建的一个线程，而且子程代码位于当前

//进程，hInstance必须为NULL。可以很简单的设定其为本应用程序的实例句柄。

//

//threadedId 与安装的钩子子程相关联的线程的标识符。如果为0，钩子子程与所有的线程关联，即为全局钩子。

//************************************

// 如果设置钩子失败

if(hKeyboardHook == 0 )

{

HookStop();

throw new Exception("SetWindowsHookEx failed.");

}

}

}

// 卸载钩子

public void HookStop()

{

bool retKeyboard = true;

if(hKeyboardHook != 0)

{

retKeyboard = UnhookWindowsHookEx(hKeyboardHook);

hKeyboardHook = 0;

}

if (!( retKeyboard))

throw new Exception("UnhookWindowsHookEx failed.");

}

vb.net在for循环中如何获取键盘按键

Public Sub TextBox_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs)

Dim SplitStr As String = ","

Dim SelectionStart As Integer = sender.SelectionStart

Dim TextLength As Integer = sender.Text.Length

'------------------------------------------------------------------

Select Case Asc(e.KeyChar)

Case Is = 8 '"回删"

Dim str As String = sender.text

Dim Array = Split(sender.text, ",", -1)

If sender.SelectionStart = str.Length Then

If str.Contains(",") Then

Dim text = ""

For x = 0 To UBound(Array) - 1

If text = "" Then

text += Array(x)

Else

text += "," + Array(x)

End If

Next

sender.text = text

sender.SelectionStart = text.Length

e.KeyChar = Chr(0)

End If

End If

Case Asc("0") To Asc("9") '" 0 to 9 "

e.KeyChar = e.KeyChar

Case Is = 44, 45 '","

Select Case TextLength

Case Is = 0

e.KeyChar = Chr(0)

Case Else

Select Case SelectionStart

Case 0

e.KeyChar = Chr(0)

Case 1 To TextLength - 1

If Mid(sender.text, SelectionStart, 1) = SplitStr Or Mid(sender.text, SelectionStart + 1, 1) = SplitStr Then

e.KeyChar = Chr(0)

Else

e.KeyChar = e.KeyChar

End If

Case TextLength

If Mid(sender.text, SelectionStart, 1) = SplitStr Then

e.KeyChar = Chr(0)

Else

e.KeyChar = e.KeyChar

End If

End Select

End Select

Case Else

e.KeyChar = Chr(0)

End Select

End Sub

这是我的程序中复制过来的,只能输入数据字与逗号还有下划线,你查一下F和J的Ass吗是多少,改写一下就OK

VB.net 软键盘 制作

Public Class Form2

Private Sub Form2_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

AddHandler Label1.MouseEnter, AddressOf LabelMouseEnter

AddHandler Label2.MouseEnter, AddressOf LabelMouseEnter

AddHandler Label1.MouseLeave, AddressOf LabelMouseLeave

AddHandler Label2.MouseLeave, AddressOf LabelMouseLeave

AddHandler Label1.MouseDown, AddressOf LabelMouseDown

AddHandler Label2.MouseDown, AddressOf LabelMouseDown

End Sub

Private Sub LabelMouseEnter(ByVal sender As Object, ByVal e As System.EventArgs)

Dim c As Label = DirectCast(sender, Label)

c.BackColor = Color.DodgerBlue

End Sub

Private Sub LabelMouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs)

Dim c As Label = DirectCast(sender, Label)

Form1.TextBox1.Text = c.Text

End Sub

Private Sub LabelMouseLeave(ByVal sender As Object, ByVal e As System.EventArgs)

Dim c As Label = DirectCast(sender, Label)

c.BackColor = SystemColors.Control

End Sub

End Class

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