在线请教：关于DRAWTEXTEX 函数

[csdndatura]

API函数申明和类型定义就不写了，以下是我的调用代码，但是在矩形中就是写不出字，
Private Sub Command1_Click()
Dim DrawRect As RECT
Dim FillName As String
Dim DrawPoint As DRAWTEXTPARAMS
Dim result As Long


DrawRect.Bottom = 70
DrawRect.Left = 80
DrawRect.Right = 200
DrawRect.Top = 10

Call FrameRect(Picture1.hdc, DrawRect, lPen)

FillName = "How are you!"

DrawPoint.cbSize = 5
DrawPoint.iLeftMargin = 1
DrawPoint.iRightMargin = 1
DrawPoint.iTabLength = 0
DrawPoint.uiLengthDrawn = Len(FillName)

Call DrawTextEx(Picture1.hdc, FillName, Len(FillName), DrawRect, DT_CENTER, DrawPoint)

End Sub

[lingll]

关键是DrawPoint.cbSize的值,不知为何你把它设置为5
应该是DrawPoint.cbSize = Len(DrawPoint)

另,在测试中,我还去掉了Call FrameRect(Picture1.hdc, DrawRect, lPen)这句,
能正常显示,
改后的代码如下

Private Sub Command1_Click()
Dim DrawRect As RECT
Dim FillName As String
Dim DrawPoint As DRAWTEXTPARAMS
Dim result As Long


DrawRect.Bottom = 70
DrawRect.Left = 80
DrawRect.Right = 200
DrawRect.Top = 10

'Call FrameRect(Picture1.hDC, DrawRect, lPen)

FillName = "How are you!"
DrawPoint.cbSize = Len(DrawPoint)
'DrawPoint.cbSize = 5
DrawPoint.iLeftMargin = 1
DrawPoint.iRightMargin = 1
DrawPoint.iTabLength = 0
DrawPoint.uiLengthDrawn = Len(FillName)

Call DrawTextEx(Picture1.hDC, FillName, Len(FillName), DrawRect, DT_CENTER, DrawPoint)

End Sub

[firechun]

cbSize=5,呵呵，大概是楼主理解错误
cbSize是DRAWTEXTPARAMS结构在内存中所占的size，楼主可能把结构size和结构成员数混淆了。在VB中该结构的每个成员为Long类型，Long在内存中占4个字节，4*5=20，用len(变量名）可以得到结构所占内存size。

[csdndatura]

谢谢两位，我已在论坛里找到了答案，在API声明中把lpDrawTextParams As RAWTEXTPARAMS 修改成lpDrawTextParams As Any，lpDrawTextParams的参数传入ByVal 0&。