vb中的commandbutton按钮上
Visual Basic允许程序员改变一个CommandButton的背景色--简单的将样式设为Graphical然后改变BackColor就行了。但却没有提供一个简单的方法去改变CommandButton的文字的颜色。 下面将告诉你怎样根据你的意愿改变CommandButton的文本颜色，而且如果按钮上有图片的话，还可以将文本显示在按钮的底部。
在工程中添加以下模块(Module):
Module s
Option Explicit
'==================================================================
' s
'
'...全部
Visual Basic允许程序员改变一个CommandButton的背景色--简单的将样式设为Graphical然后改变BackColor就行了。但却没有提供一个简单的方法去改变CommandButton的文字的颜色。
下面将告诉你怎样根据你的意愿改变CommandButton的文本颜色，而且如果按钮上有图片的话，还可以将文本显示在按钮的底部。
在工程中添加以下模块(Module):
Module s
Option Explicit
'==================================================================
' s
'
' 本模块可让你改变命令按钮的文本颜色。
' 使用方法:
'
' - 在设计时将文本的Style设为Graphical。
'
' - 随意设定背景色和图象属性。
'
' - 在FORM_Load中调用 SetButton :
' SetButton Command1。
hWnd, vbBlue
' (你可以任意次的调用该过程甚至不必先调用 RemoveButton。)
'
' - 在FORM_Unload中调用 RemoveButton :
' RemoveButton Command1。
hWnd
'
'==================================================================
Private Type RECT
Left As Long
Top As Long
Right As Long
Bottom As Long
End Type
Private Declare Function GetParent Lib "user32" _
(ByVal hWnd As Long) As Long
Private Declare Function GetWindowLong Lib "user32" Alias _
"GetWindowLongA" (ByVal hWnd As Long, _
ByVal nIndex As Long) As Long
Private Declare Function SetWindowLong Lib "user32" Alias _
"SetWindowLongA" (ByVal hWnd As Long, ByVal nIndex As Long, _
ByVal dwNewLong As Long) As Long
Private Const GWL_WNDPROC = (-4)
Private Declare Function GetProp Lib "user32" Alias "GetPropA" _
(ByVal hWnd As Long, ByVal lpString As String) As Long
Private Declare Function SetProp Lib "user32" Alias "SetPropA" _
(ByVal hWnd As Long, ByVal lpString As String, _
ByVal hData As Long) As Long
Private Declare Function RemoveProp Lib "user32" Alias _
"RemovePropA" (ByVal hWnd As Long, _
ByVal lpString As String) As Long
Private Declare Function CallWindowProc Lib "user32" Alias _
"CallWindowProcA" (ByVal lpPrevWndFunc As Long, _
ByVal hWnd As Long, ByVal Msg As Long, ByVal wParam As Long, _
ByVal lParam As Long) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" _
(Destination As Any, Source As Any, ByVal Length As Long)
'Owner draw constants
Private Const ODT_BUTTON = 4
Private Const ODS_SELECTED = &H1
'Window messages we're using
Private Const WM_DESTROY = &H2
Private Const WM_DRAWITEM = &H2B
Private Type DRAWITEMSTRUCT
CtlType As Long
CtlID As Long
itemID As Long
itemAction As Long
itemState As Long
hwndItem As Long
hDC As Long
rcItem As RECT
itemData As Long
End Type
Private Declare Function GetWindowText Lib "user32" Alias _
"GetWindowTextA" (ByVal hWnd As Long, ByVal lpString As String, _
ByVal cch As Long) As Long
'Various GDI painting-related functions
Private Declare Function DrawText Lib "user32" Alias "DrawTextA" _
(ByVal hDC As Long, ByVal lpStr As String, ByVal nCount As Long, _
lpRect As RECT, ByVal wFORMat As Long) As Long
Private Declare Function SetTextColor Lib "gdi32" (ByVal hDC As Long, _
ByVal crColor As Long) As Long
Private Declare Function SetBkMode Lib "gdi32" (ByVal hDC As Long, _
ByVal nBkMode As Long) As Long
Private Const TRANSPARENT = 1
Private Const DT_CENTER = &H1
Public Enum TextVAligns
DT_VCENTER = &H4
DT_BOTTOM = &H8
End Enum
Private Const DT_SINGLELINE = &H20
Private Sub DrawButton(ByVal hWnd As Long, ByVal hDC As Long, _
rct As RECT, ByVal nState As Long)
Dim s As String
Dim va As TextVAligns
va = GetProp(hWnd, "VBTVAlign")
'Prepare DC for drawing
SetBkMode hDC, TRANSPARENT
SetTextColor hDC, GetProp(hWnd, "VBTForeColor")
'Prepare a text buffer
s = String$(255, 0)
'What should we print on the button?
GetWindowText hWnd, s, 255
'Trim off nulls
s = Left$(s, InStr(s, Chr$(0)) - 1)
If va = DT_BOTTOM Then
'Adjust specially for VB's CommandButton control
rct。
Bottom = rct。Bottom - 4
End If
If (nState And ODS_SELECTED) = ODS_SELECTED Then
'Button is in down state - offset
'the text
rct。
Left = rct。Left + 1
rct。Right = rct。Right + 1
rct。Bottom = rct。Bottom + 1
rct。Top = rct。Top + 1
End If
DrawText hDC, s, Len(s), rct, DT_CENTER Or DT_SINGLELINE _
Or va
End Sub
Public Function ExtButtonProc(ByVal hWnd As Long, _
ByVal wMsg As Long, ByVal wParam As Long, _
ByVal lParam As Long) As Long
Dim lOldProc As Long
Dim di As DRAWITEMSTRUCT
lOldProc = GetProp(hWnd, "ExtBtnProc")
ExtButtonProc = CallWindowProc(lOldProc, hWnd, wMsg, wParam, lParam)
If wMsg = WM_DRAWITEM Then
CopyMemory di, ByVal lParam, Len(di)
If di。
CtlType = ODT_BUTTON Then
If GetProp(di。hwndItem, "VBTCustom") = 1 Then
DrawButton di。hwndItem, di。
hDC, di。rcItem, _
emState
End If
End If
ElseIf wMsg = WM_DESTROY Then
ExtButtonUnSubclass hWnd
End If
End Function
Public Sub ExtButtonSubclass(hWndFORM As Long)
Dim l As Long
l = GetProp(hWndFORM, "ExtBtnProc")
If l <> 0 Then
'Already subclassed
Exit Sub
End If
SetProp hWndFORM, "ExtBtnProc", _
GetWindowLong(hWndFORM, GWL_WNDPROC)
SetWindowLong hWndFORM, GWL_WNDPROC, AddressOf ExtButtonProc
End Sub
Public Sub ExtButtonUnSubclass(hWndFORM As Long)
Dim l As Long
l = GetProp(hWndFORM, "ExtBtnProc")
If l = 0 Then
'Isn't subclassed
Exit Sub
End If
SetWindowLong hWndFORM, GWL_WNDPROC, l
RemoveProp hWndFORM, "ExtBtnProc"
End Sub
Public Sub SetButton(ByVal hWnd As Long, _
ByVal lForeColor As Long, _
Optional ByVal VAlign As TextVAligns = DT_VCENTER)
Dim hWndParent As Long
hWndParent = GetParent(hWnd)
If GetProp(hWndParent, "ExtBtnProc") = 0 Then
ExtButtonSubclass hWndParent
End If
SetProp hWnd, "VBTCustom", 1
SetProp hWnd, "VBTForeColor", lForeColor
SetProp hWnd, "VBTVAlign", VAlign
End Sub
Public Sub RemoveButton(ByVal hWnd As Long)
RemoveProp hWnd, "VBTCustom"
RemoveProp hWnd, "VBTForeColor"
RemoveProp hWnd, "VBTVAlign"
End Sub
将FORM命名为frmDemo。
添加4个CommandButton，不必更改它们的名称，将它们的Style设为Graphical，给第3个按钮设置一幅图片。
CommandButton也可以放置在一个容器如PictureBox或Frame中，模块会判断，如果需要的话将CommandButton的容器也子类化。
在FORM中加入如下代码：
Private Sub FORM_Load()
'Initialize each button color。
SetButton Command1。hWnd, vbRed
SetButton Command2。
hWnd, &H8000& '深绿色
'Assign this one a DT_BOTTOM alignment because
SetButton Command3。hWnd, vbBlue, DT_BOTTOM '含有图片，将文本放置在按钮底部
SetButton Command4。
hWnd, &H8080& '暗棕黄色
End Sub
Private Sub FORM_Unload(Cancel As Integer)
'手动解除按钮的子类化
'这并不是必须的
RemoveButton Command1。
hWnd
RemoveButton Command2。hWnd
RemoveButton Command3。hWnd
RemoveButton Command4。hWnd
End Sub 。
收起
