在VB中用PictureBox控件实现特殊符号工具栏

　　在几年前的一个试题库项目里，有一个这样的需求，需要输入特殊符号。因为各种不同的试题中，需要使用的特殊符号特别多，并且，不同类型的客户，需要输入的题目多种多样，能够用到的特殊符号也是五花八门。因此系统内置的特殊符号很难满足所有用户的要求。

　　根据这种需求，需要在程序中实现特殊符号的输入，系统内部除了要内置比较丰富的特殊符号之外，还要允许用户根据自己的情况进行自定义。

　　笔者经过研究，虽然走了一些弯路，但是，最终还是使用PictureBox控件开发出了特殊符号工具栏。

　　先说一下研究的历程吧，说到工具栏，大家首先想到的是使用ToolBar工具栏控件，笔者开始也是使用的这个控件，但是遇到了一些问题。虽然ToolBar控件使用起来比较简单，但是在此需求下，有一些问题，如：

1、ToolBar的各个按钮需要使用图片，而系统中的特殊符号需要自定义，如果让用户自己做图片恐怕不太可行；

2、用程序实现在运行时动态添加ToolBar中的按钮，也比较麻烦；

3、特殊符号按钮数量比较多，速度是一个问题（笔者研究时，只加了30个左右的按钮，运行之后的速度就不行了，加载慢，运行时闪烁）；

 

　　针对以上问题，使用ToolBar控件，不太可行，因此马上转变思路，经过思考，决定采用PictureBox控件进行自绘工具栏，每个特殊符号按钮的鼠标移动、移出、点击、抬起效果与ToolBar工具栏按钮完全一样。特殊符号保存在文本文件中，动态加载，另外还可以写一个维护程序，维护这个特殊符号文件中的内容。

 

源码下载地址：http://www.j2soft.cn/static_html/200511241415296539admin.html

 

系统演示界面如下：

使用界面：

 

设置界面：

 

源码下载地址：http://www.j2soft.cn/static_html/200511241415296539admin.html

 

实现程序如下：
1、添加一个模块文件，内容如下：

 

Option Explicit

Public Type RECT
  Left As Long
  Top As Long
  Right As Long
  Bottom As Long
End Type

Public Const DC_ACTIVE = &H1
Public Const DC_ICON = &H4
Public Const DC_TEXT = &H8
Public Const DC_GRADIENT = &H20
Public Const DFCS_PUSHED = &H200
Public Const DFCS_CAPTIONCLOSE = &H0

Public Declare Function ReleaseCapture Lib "user32" () As Long
Public Declare Function DrawCaption Lib "user32" (ByVal hwnd As Long, ByVal hDC As Long, pcRect As RECT, ByVal un As Long) As Long
Public Declare Function DrawFrameControl Lib "user32" (ByVal hDC As Long, lpRect As RECT, ByVal un1 As Long, ByVal un2 As Long) As Long
Public Declare Function SetRect Lib "user32" (lpRect As RECT, ByVal X1 As Long, ByVal Y1 As Long, ByVal X2 As Long, ByVal Y2 As Long) As Long
Public Declare Function SetWindowText Lib "user32" Alias "SetWindowTextA" (ByVal hwnd As Long, ByVal lpString As String) As Long
Public Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long

Public Sub ErrView(ErrS As String)
  MsgBox "应用程序产生错误！" & vbCrLf & "错误描述为：" & ErrS & "！", vbExclamation, "试题库!"
End Sub

 

 

2、窗口内容如下：

 

Option Explicit

Dim Ctl As Control
Dim TbFlag As Boolean, StartFlag As Boolean
Dim StrSpecial() As String
Dim IntLen As Integer, TbXo As Integer, TbYo As Integer
Dim SpecialIndexFirst As Integer, SpecialIndexLast As Integer

Private Sub CmdExit_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
  Dim rt As RECT
 
  If Button = 1 Then
    SetRect rt, 0, 0, 13, 11
    DrawFrameControl cmdExit.hDC, rt, 1, DFCS_PUSHED
  End If
 
  ReleaseCapture
End Sub

Private Sub CmdExit_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
  Dim rt As RECT

  If Button = 1 Then
    SetRect rt, 0, 0, 13, 11
    DrawFrameControl cmdExit.hDC, rt, 1, DFCS_PUSHED
  ElseIf Button = 0 Then
    SetRect rt, 0, 0, 13, 11
    DrawFrameControl cmdExit.hDC, rt, 1, DFCS_CAPTIONCLOSE
  End If
End Sub

'特殊符号工具栏的关闭按钮
Private Sub cmdexit_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
On Error GoTo Errhandle
  Dim rt As RECT
 
  SetRect rt, 0, 0, 13, 11
  DrawFrameControl cmdExit.hDC, rt, 1, DFCS_CAPTIONCLOSE

  PicSpecial.Visible = False
  PicSpecial.Height = 25
   
  Erase StrSpecial  '重置特殊符号数组，释放内存
  Ctl.SetFocus

  Exit Sub
Errhandle:
  ErrView Err.Description
End Sub

Private Sub CmdExit_Paint()
  Dim rt As RECT
 
  SetRect rt, 0, 0, 13, 11
  DrawFrameControl cmdExit.hDC, rt, 1, DFCS_CAPTIONCLOSE
End Sub

Private Sub Form_Activate()
    Set Ctl = Me.ActiveControl
    mnuSpecialChar_Click
End Sub

Private Sub Form_Load()
    SetWindowText Pic_Btns.hwnd, "特殊符号"
End Sub

Private Sub mnuSpecialChar_Click()
    Dim i As Integer
    Dim s As String
   
    If Right(App.Path, 1) <> "/" Then
      s = App.Path + "/" + "Char.Chr"
    Else
      s = App.Path + "Char.chr"
    End If
   
    '检测字符集文件是否存在
    If Dir(s) = "" Then
      MsgBox "特殊字符集文件丢失！特殊工具栏里的按钮将不可用！", vbCritical, "警告"
   
      Exit Sub
    End If
   
    '打开字符集文件
    Open s For Input As #1
    Line Input #1, s
    Close #1 '关闭字符集文件
   
    IntLen = Len(s) + 2
    ReDim StrSpecial(IntLen)
   
    For i = 1 To IntLen - 2
      StrSpecial(i) = Mid(s, i, 1)
    Next
   
    StrSpecial(IntLen - 1) = "(" & vbTab & vbTab & ")"
    StrSpecial(IntLen) = "________"
   
    If IntLen Mod 24 = 0 Then
      Pic_Btn.Height = IntLen + 25
    Else
      Pic_Btn.Height = Int(IntLen / 24) * 24 + 49
    End If
   
    If Pic_Btn.Height <= 169 Then
      PicSpecial.Height = Pic_Btn.Height
      PicSpecial.Width = 583
      Pic_Btns.Width = 581
      Pic_Btn.Top = 20
      cmdExit.Left = 566
    Else
      PicSpecial.Height = 169
      PicSpecial.Width = 598
      Pic_Btns.Width = 600
      cmdExit.Left = 581
      VScroll.Height = 150
   
      VScroll.Min = -20
      VScroll.Max = Pic_Btn.Height - 189
    End If
   
    If VScroll.Min = -20 Then VScroll.Value = -20
   
    PicSpecial.Top = (Me.ScaleHeight - PicSpecial.ScaleHeight) - 50
    PicSpecial.Left = (Me.ScaleWidth - PicSpecial.ScaleWidth) / 2
   
    PicSpecial.Visible = True
End Sub

Private Sub Pic_Btns_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
On Error GoTo Errhandle
  If Button = 1 Then
    ReleaseCapture
    SendMessage PicSpecial.hwnd, &HA1, 2, 0
  End If
 
  Exit Sub
Errhandle:
  ErrView Err.Description
End Sub

Private Sub Pic_Btns_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
  PicBtnDraw
End Sub

Private Sub Pic_Btns_Paint()
  Dim rt As RECT
 
  rt.Left = 0
  rt.Top = 0
  rt.Right = PicSpecial.ScaleWidth
  rt.Bottom = 16
 
  DrawCaption Pic_Btns.hwnd, Pic_Btns.hDC, rt, DC_ACTIVE Or DC_GRADIENT Or DC_TEXT Or DC_ICON
End Sub

Private Sub VScroll_Change()
On Error Resume Next
  Dim TmpI As Integer

  TmpI = VScroll.Value + 20

  If TmpI Mod 24 = 0 Then
    Pic_Btn.Top = -VScroll.Value
  Else
    Pic_Btn.Top = (TmpI Mod 24) - VScroll.Value
  End If
End Sub

Private Sub VScroll_GotFocus()
On Error Resume Next
  Ctl.SetFocus
  PicBtnDraw
End Sub

Private Sub Pic_Btn_GotFocus()
On Error Resume Next
  Ctl.SetFocus
End Sub

'特殊符号工具栏按钮
Private Sub Pic_Btn_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
On Error GoTo Errhandle
  Dim Tmp_Index As Integer

  '确定特殊符号索引
  Tmp_Index = 1 + X / 24 + (Y / 24) * 24

  '判断索引是否在当前显示的区域内
  If X >= 576 Or Tmp_Index < SpecialIndexFirst Or Tmp_Index > SpecialIndexLast Then Exit Sub

  If Button = 1 Then
    Dim Xs As Integer, Ys As Integer

    Xs = X / 24
    Ys = Y / 24

    Pic_Btn.ForeColor = &H8000000F
    Pic_Btn.Line (TbXo * 24, TbYo * 24)-(TbXo * 24 + 24, TbYo * 24)
    Pic_Btn.Line (TbXo * 24, TbYo * 24)-(TbXo * 24, TbYo * 24 + 24)
    Pic_Btn.Line (TbXo * 24 + 24, TbYo * 24 + 1)-(TbXo * 24 + 24, TbYo * 24 + 25)
    Pic_Btn.Line (TbXo * 24, TbYo * 24 + 24)-(TbXo * 24 + 24, TbYo * 24 + 24)

    Pic_Btn.ForeColor = vbWhite
    Pic_Btn.Line (Xs * 24 + 24, Ys * 24 + 1)-(Xs * 24 + 24, Ys * 24 + 25)
    Pic_Btn.Line (Xs * 24, Ys * 24 + 24)-(Xs * 24 + 24, Ys * 24 + 24)
    Pic_Btn.ForeColor = vbBlack
    Pic_Btn.Line (Xs * 24, Ys * 24)-(Xs * 24 + 24, Ys * 24)
    Pic_Btn.Line (Xs * 24, Ys * 24)-(Xs * 24, Ys * 24 + 25)

    TbXo = Xs
    TbYo = Ys
    TbFlag = True
  End If

  Exit Sub
Errhandle:
  ErrView Err.Description
End Sub

'绘制特殊符号工具栏
Private Sub Pic_Btn_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
On Error Resume Next
  Dim Tmp_Index As Integer

  '确定特殊符号索引
  Tmp_Index = 1 + X / 24 + (Y / 24) * 24

  '判断索引是否在当前显示区域内
  If X >= 576 Or Tmp_Index < SpecialIndexFirst Or Tmp_Index > SpecialIndexLast Then
    Pic_Btn.ForeColor = &H8000000F

    Pic_Btn.Line (TbXo * 24, TbYo * 24)-(TbXo * 24 + 24, TbYo * 24)
    Pic_Btn.Line (TbXo * 24, TbYo * 24)-(TbXo * 24, TbYo * 24 + 24)
    Pic_Btn.Line (TbXo * 24 + 24, TbYo * 24 + 1)-(TbXo * 24 + 24, TbYo * 24 + 25)
    Pic_Btn.Line (TbXo * 24, TbYo * 24 + 24)-(TbXo * 24 + 24, TbYo * 24 + 24)

    Exit Sub
  End If

  If TbFlag Then Exit Sub

  Dim Xs As Integer, Ys As Integer

  Xs = X / 24
  Ys = Y / 24

  Pic_Btn.ForeColor = &H8000000F
  Pic_Btn.Line (TbXo * 24, TbYo * 24)-(TbXo * 24 + 24, TbYo * 24)
  Pic_Btn.Line (TbXo * 24, TbYo * 24)-(TbXo * 24, TbYo * 24 + 24)
  Pic_Btn.Line (TbXo * 24 + 24, TbYo * 24 + 1)-(TbXo * 24 + 24, TbYo * 24 + 25)
  Pic_Btn.Line (TbXo * 24, TbYo * 24 + 24)-(TbXo * 24 + 24, TbYo * 24 + 24)

  Pic_Btn.ForeColor = vbBlack
  Pic_Btn.Line (Xs * 24 + 24, Ys * 24 + 1)-(Xs * 24 + 24, Ys * 24 + 25)
  Pic_Btn.Line (Xs * 24, Ys * 24 + 24)-(Xs * 24 + 24, Ys * 24 + 24)
  Pic_Btn.ForeColor = vbWhite
  Pic_Btn.Line (Xs * 24, Ys * 24)-(Xs * 24 + 24, Ys * 24)
  Pic_Btn.Line (Xs * 24, Ys * 24)-(Xs * 24, Ys * 24 + 25)

  TbXo = Xs
  TbYo = Ys
End Sub

Private Sub Pic_Btn_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
'On Error GoTo Errhandle
  Dim Tmp_Index As Integer

  If Button = 1 Then
    TbFlag = False

    '确定特殊符号索引
    Tmp_Index = 1 + X / 24 + (Y / 24) * 24

    '判断索引是否在当前显示区域内
    If X >= 576 Or Tmp_Index < SpecialIndexFirst Or Tmp_Index > SpecialIndexLast Then Exit Sub

    If TypeOf Ctl Is TextBox Or TypeOf Ctl Is TextBox Then
      StartFlag = True

      Ctl.SelText = StrSpecial(Tmp_Index)
      Ctl.SetFocus
    End If
  End If

  Exit Sub
Errhandle:
  ErrView Err.Description
End Sub

'重绘特殊符号工具栏
Private Sub Pic_Btn_Paint()
On Error GoTo Errhandle
  Dim i As Integer, X As Integer, Y As Integer

  '此函数的功能是：只重画显示的部分，而不是重画所有的特殊符号
  Pic_Btn.ForeColor = vbBlack

  '根据容器的顶点计算重画的顶部索引,如果顶点是20,则从第
  '一个开始,否则从下一行开始Pic_Btn.Top 的范围始终小于等
  '于-20,并且是按24的倍数递减的,即:-20,-44,-68,-92……
  SpecialIndexFirst = 21 - Pic_Btn.Top

  X = 5: Y = 5 + SpecialIndexFirst

  '根据顶点索引,计算最后一个索引,一页显示144个特殊符号(6行,24列)
  SpecialIndexLast = SpecialIndexFirst + 143
  '判断是否超过实际的特殊符号个数
  SpecialIndexLast = IIf(SpecialIndexLast > IntLen, IntLen, SpecialIndexLast)

  '循环重画特殊符号
  For i = SpecialIndexFirst To SpecialIndexLast
    Pic_Btn.CurrentX = X
    Pic_Btn.CurrentY = Y

    If i = IntLen - 1 Then
      Pic_Btn.Print "()"
    Else
      If i = IntLen Then
        Pic_Btn.Print "__"
      Else
        Pic_Btn.Print StrSpecial(i)
      End If
    End If

    X = X + 24
    '够一行则从下一行的开头重新开始
    If i Mod 24 = 0 Then X = 5: Y = Y + 24
  Next

  Exit Sub
Errhandle:
  ErrView Err.Description
End Sub

Private Sub PicBtnDraw()
On Error Resume Next
  Pic_Btn.ForeColor = &H8000000F

  Pic_Btn.Line (TbXo * 24, TbYo * 24)-(TbXo * 24 + 24, TbYo * 24)
  Pic_Btn.Line (TbXo * 24, TbYo * 24)-(TbXo * 24, TbYo * 24 + 24)
  Pic_Btn.Line (TbXo * 24 + 24, TbYo * 24 + 1)-(TbXo * 24 + 24, TbYo * 24 + 25)
  Pic_Btn.Line (TbXo * 24, TbYo * 24 + 24)-(TbXo * 24 + 24, TbYo * 24 + 24)

  Dim rt As RECT
 
  SetRect rt, 0, 0, 13, 11
  DrawFrameControl cmdExit.hDC, rt, 1, DFCS_CAPTIONCLOSE
 
  TbFlag = False
End Sub

 

 

　　至此，特殊符号工具栏实现完成，大家也许会说，现在的汉字输入法都内置很多特殊符号，并且word中也有很多的特殊符号。但是毕竟都是别人提供的，内容不允许修改，并且在自己的系统内部，使用时还要调用别的程序，比较麻烦。

 

源码下载地址：http://www.j2soft.cn/static_html/200511241415296539admin.html