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问题描述

我一直在使用Daniel Klann编写的标准密码文本框()来隐藏密码输入。

I have been using the standard password textbox written by Daniel Klann (http://www.ozgrid.com/forum/showthread.php?t=72794) to hide the password inputs.

主要的问题是标准的 InputBox 返回空字段并取消相同的方式。 Application.InputBox 但是可以在取消时返回 False

The main problem is that the standard InputBox returns empty fields and cancel the same way. Application.InputBox however is capable of returning a False on cancel.

更新Daniel Klann的脚本使用 Application.InputBox 不在我的位置。这是怎么做的?

Updating Daniel Klann's script to work with the Application.InputBox is beyond me. How would this be done?

这是Daniel的代码:

Here is Daniel's code:

Option Explicit 

 '////////////////////////////////////////////////////////////////////
 'Password masked inputbox
 'Allows you to hide characters entered in a VBA Inputbox.
 '
 'Code written by Daniel Klann
 'http://www.danielklann.com/
 'March 2003

 '// Kindly permitted to be amended
 '// Amended by Ivan F Moala
 '// http://www.xcelfiles.com
 '// April 2003
 '// Works for Xl2000+ due the AddressOf Operator
 '////////////////////////////////////////////////////////////////////

 '********************   CALL FROM FORM *********************************
 '    Dim pwd As String
 '
 '    pwd = InputBoxDK("Please Enter Password Below!", "Database Administration Security Form.")
 '
 '    'If no password was entered.
 '    If pwd = "" Then
 '        MsgBox "You didn't enter a password!  You must enter password to 'enter the Administration Screen!" _
 '        , vbInformation, "Security Warning"
 '    End If
 '**************************************



 'API functions to be used
Private Declare Function CallNextHookEx _ 
Lib "user32" ( _ 
ByVal hHook As Long, _ 
ByVal ncode As Long, _ 
ByVal wParam As Long, _ 
lParam As Any) _ 
As Long 

Private Declare Function GetModuleHandle _ 
Lib "kernel32" _ 
Alias "GetModuleHandleA" ( _ 
ByVal lpModuleName As String) _ 
As Long 

Private Declare Function SetWindowsHookEx _ 
Lib "user32" _ 
Alias "SetWindowsHookExA" ( _ 
ByVal idHook As Long, _ 
ByVal lpfn As Long, _ 
ByVal hmod As Long, _ 
ByVal dwThreadId As Long) _ 
As Long 

Private Declare Function UnhookWindowsHookEx _ 
Lib "user32" ( _ 
ByVal hHook As Long) _ 
As Long 

Private Declare Function SendDlgItemMessage _ 
Lib "user32" Alias "SendDlgItemMessageA" ( _ 
ByVal hDlg As Long, _ 
ByVal nIDDlgItem As Long, _ 
ByVal wMsg As Long, _ 
ByVal wParam As Long, _ 
ByVal lParam As Long) _ 
As Long 

Private Declare Function GetClassName _ 
Lib "user32" _ 
Alias "GetClassNameA" ( _ 
ByVal hWnd As Long, _ 
ByVal lpClassName As String, _ 
ByVal nMaxCount As Long) _ 
As Long 

Private Declare Function GetCurrentThreadId _ 
Lib "kernel32" () _ 
As Long 

 'Constants to be used in our API functions
Private Const EM_SETPASSWORDCHAR = &HCC 
Private Const WH_CBT = 5 
Private Const HCBT_ACTIVATE = 5 
Private Const HC_ACTION = 0 

Private hHook As Long 

Public Function NewProc(ByVal lngCode As Long, _ 
    ByVal wParam As Long, _ 
    ByVal lParam As Long) As Long 

    Dim RetVal 
    Dim strClassName As String, lngBuffer As Long 

    If lngCode < HC_ACTION Then 
        NewProc = CallNextHookEx(hHook, lngCode, wParam, lParam) 
        Exit Function 
    End If 

    strClassName = String$(256, " ") 
    lngBuffer = 255 

    If lngCode = HCBT_ACTIVATE Then 'A window has been activated
        RetVal = GetClassName(wParam, strClassName, lngBuffer) 
        If Left$(strClassName, RetVal) = "#32770" Then 'Class name of the Inputbox
             'This changes the edit control so that it display the password character *.
             'You can change the Asc("*") as you please.
            SendDlgItemMessage wParam, &H1324, EM_SETPASSWORDCHAR, Asc("*"), &H0 
        End If 
    End If 

     'This line will ensure that any other hooks that may be in place are
     'called correctly.
    CallNextHookEx hHook, lngCode, wParam, lParam 

End Function 

 '// Make it public = avail to ALL Modules
 '// Lets simulate the VBA Input Function
Public Function InputBoxDK(Prompt As String, Optional Title As String, _ 
    Optional Default As String, _ 
    Optional Xpos As Long, _ 
    Optional Ypos As Long, _ 
    Optional Helpfile As String, _ 
    Optional Context As Long) As String 

    Dim lngModHwnd As Long, lngThreadID As Long 

     '// Lets handle any Errors JIC! due to HookProc> App hang!
    On Error Goto ExitProperly 
    lngThreadID = GetCurrentThreadId 
    lngModHwnd = GetModuleHandle(vbNullString) 

    hHook = SetWindowsHookEx(WH_CBT, AddressOf NewProc, lngModHwnd, lngThreadID) 
    If Xpos Then 
        InputBoxDK = InputBox(Prompt, Title, Default, Xpos, Ypos, Helpfile, Context) 
    Else 
        InputBoxDK = InputBox(Prompt, Title, Default, , , Helpfile, Context) 
    End If 

ExitProperly: 
    UnhookWindowsHookEx hHook 

End Function 


推荐答案

不,没有。它返回一个空指针取消,空字符串为空输入。

No it does not. It returns a null pointer on cancel and an empty string for empty input.

Dim s As String
s = InputBox("Test")

If StrPtr(s) = 0 Then
  'Cancel pressed
Else
  'Ok pressed
End If

因为 InputBoxDK 返回 InputBox 的值不变,相同的逻辑适用于它。

Because InputBoxDK returns the InputBox's value unchanged, same logic applies to it.

这篇关于具有取消功能的VBA密码输入的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!

10-12 12:05