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07	如何搜尋某路徑下的所有副檔名(含所有子目錄)
	'放一個listbox和button... Public Class Form1 Private Declare Function GetFileAttributes Lib "kernel32" Alias "GetFileAttributesA" (ByVal lpFileName As String) As Long Private FoundFile() As String Private ntx As Long Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click ntx = 0 Call GetDirPath("E:\工具資料夾\", ".exe,.zip") '已修改成可搜多種副檔名 Me.Text = "ok" For i As Integer = 0 To UBound(FoundFile) ListBox1.Items.Add(FoundFile(i)) Next i End Sub Private Sub GetDirPath(ByVal CurrentPath As String, ByVal SearFile As String) Dim nI As Integer, nDirectory As Integer, i As Long Dim sFileName As String, sDirectoryList() As String Dim searfiles() As String = Split(SearFile, ",") '☆多種副檔名 Me.Text = "搜尋中-" & CurrentPath sFileName = Dir(CurrentPath, vbHidden Or vbDirectory Or vbReadOnly Or vbSystem) Do While sFileName <> "" For j As Integer = 0 To searfiles.Length - 1 '☆ If UCase(sFileName) Like UCase(searfiles(j)) Then i = GetFileAttributes(CurrentPath + sFileName) If (i And vbDirectory) = 0 Then ReDim Preserve FoundFile(ntx) FoundFile(ntx) = CurrentPath + sFileName ntx = ntx + 1 End If End If Next j If sFileName <> "." And sFileName <> ".." Then If GetFileAttributes(CurrentPath & sFileName) _ And vbDirectory Then nDirectory = nDirectory + 1 ReDim Preserve sDirectoryList(nDirectory) sDirectoryList(nDirectory) = CurrentPath & sFileName End If End If sFileName = Dir() Loop Application.DoEvents() For nI = 1 To nDirectory GetDirPath(sDirectoryList(nI) & "\", SearFile) Next nI End Sub End Class
06	偷天換日-把PropertyGrid中Image屬性的[…]換成自訂的按鈕
	'用API蓋住 image [...]的方式 'PictureBox,PropertyGrid,Button,Timer 各一個 Public Class Form1 Structure RECT Public Left As Integer Public Top As Integer Public Right As Integer Public Bottom As Integer End Structure Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Integer, ByVal hWnd2 As Integer, ByVal lpsz1 As String, ByVal lpsz2 As String) As Integer Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Integer Private Declare Function GetWindowRect Lib "user32" (ByVal hwnd As Integer, ByRef lpRect As RECT) As Integer Private Declare Function GetClassName Lib "user32" Alias "GetClassNameA" (ByVal hwnd As Integer, ByVal lpClassName As String, ByVal nMaxCount As Integer) As Integer Private Declare Function IsWindowVisible Lib "user32" (ByVal hwnd As Integer) As Integer Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click '原本寫在這開檔,但會被focus切換影響...故改至MouseDown End Sub Private Sub Button1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Button1.MouseDown Dim OPF As New OpenFileDialog OPF.Filter = "圖檔\|.gif;.jpg;.bmp;.png" If OPF.ShowDialog = DialogResult.OK Then PictureBox1.ImageLocation = OPF.FileName '載入圖形 PropertyGrid1.SelectedObject = PictureBox1 '重載更新 (.refresh 好像沒用~@@) End If End Sub Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Timer1.Enabled = True : Timer1.Interval = 100 With Button1 .Visible = False .BackColor = Color.Red .Size = New Size(17, 17) .Text = "…" End With End Sub Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick Dim rect1 As RECT Dim aWnd As Integer = Me.Handle '表單 Static v As Integer If PropertyGrid1.SelectedGridItem.Label = "Image" Then '如果選在 image 屬性上 Dim bWnd As Integer = FindWindowEx(aWnd, 0, vbNullString, "PropertyGrid") '找到PropertyGrid Dim cWnd As Integer = FindWindowEx(bWnd, 0, vbNullString, "PropertyGridView") '找到PropertyGrid內容區 Dim lpClassName As String = Space$(256) GetClassName(cWnd, lpClassName, 256) Dim lpClassName1 As String = Split(lpClassName, "app")(1) '取得表單後編號...找[...]時有用到! Dim dWnd As Integer = FindWindowEx(cWnd, 0, "WindowsForms10.BUTTON.app" & lpClassName1, vbNullString) If dWnd <> 0 Then If IsWindowVisible(dWnd) Then '是不是在可見範圍內 Call GetWindowRect(dWnd, rect1) '取得位置範圍 Dim brd As Integer = (Me.Width - Me.ClientRectangle.Width) / 2 '要扣除的表單邊框 Button1.Location = New Point(rect1.Left - Me.Left - brd - 1, rect1.Top - Me.Top - (Me.Height - Me.ClientRectangle.Height - brd) - 1) Button1.BringToFront() Button1.Visible = True v = 0 Else v = v + 1 If v = 2 Then Button1.Visible = False : v = 0 '判斷到2次才確定隱藏!(原本的[...]有點遲鈍...要等它一下!) End If Else Button1.Visible = False End If Else Button1.Visible = False End If End Sub Private Sub PropertyGrid1_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles PropertyGrid1.GotFocus Timer1.Enabled = True '得到駐點才動 End Sub Private Sub PropertyGrid1_LostFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles PropertyGrid1.LostFocus Timer1.Enabled = False End Sub End Class
05	圖形的旋轉與縮放
	'滑動滑鼠滾輪縮放大小，按住F1再滑滾輪(可前、後滾)旋轉圖片 Public Class Form1 Dim img1 As Image, imgS As Image Const PI = 3.14159265 Dim k As Boolean Dim ang As Integer '目前的角度 Dim dang As Integer = 5 '每次旋轉的角度 Dim dsize As Integer = 1 '每次縮放的差值 Private Sub Form1_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown If e.KeyCode = Keys.F1 Then k = True End Sub Private Sub Form1_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyUp If e.KeyCode = Keys.F1 Then k = False End Sub Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Me.KeyPreview = True '接收鍵盤 'PictureBox1 自行載入你自己的圖 PictureBox1.SizeMode = PictureBoxSizeMode.StretchImage '設為可縮放 imgS = PictureBox1.Image '暫存原圖 End Sub Private Sub Form1_MouseWheel(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseWheel '縮放 If e.Delta > 0 And k = False Then PictureBox1.Size = PictureBox1.Size.Add(PictureBox1.Size, New Size(dsize, dsize)) If e.Delta < 0 And k = False Then PictureBox1.Size = PictureBox1.Size.Subtract(PictureBox1.Size, New Size(dsize, dsize)) '旋轉 If e.Delta > 0 And k = True Then ang = (ang + dang) Mod 360 : PictureBox1.Image = Rotate(imgS, ang) If e.Delta < 0 And k = True Then ang = (ang - dang) Mod 360 : PictureBox1.Image = Rotate(imgS, ang) End Sub Public Function Rotate(ByVal imgSource As Image, ByVal degree As Integer) As Image degree = degree Mod 360 If degree < 0 Then degree = 360 + degree If imgSource Is Nothing Then Return Nothing Dim ImgTarget As Image = Nothing Try Select Case degree Case 0 To 89 ImgTarget = Rotate0_90(imgSource, degree) Case 90 To 179 ImgTarget = Rotate90_180(imgSource, degree) Case 180 To 269 ImgTarget = Rotate180_270(imgSource, degree) Case 270 To 359 ImgTarget = Rotate270_360(imgSource, degree) End Select Catch End Try Return ImgTarget End Function Private Function Rotate0_90(ByVal img As Image, ByVal degree As Integer) As Image Dim ImgTarget As Bitmap Dim alpha As Double = (degree / 180) * PI Dim iWidth As Integer = img.Width * Math.Cos(alpha) + img.Height * Math.Sin(alpha) Dim iHeight As Integer = img.Width * Math.Sin(alpha) + img.Height * Math.Cos(alpha) ImgTarget = New Bitmap(iWidth, iHeight, Drawing.Imaging.PixelFormat.Format24bppRgb) Dim g As Graphics g = Graphics.FromImage(ImgTarget) g.TranslateTransform(img.Height * Math.Sin(alpha), 0) g.RotateTransform(degree) g.DrawImage(img, New Rectangle(0, 0, img.Width, img.Height)) Return ImgTarget End Function Private Function Rotate90_180(ByVal img As Image, ByVal degree As Integer) As Image Dim ImgTarget As Bitmap Dim alpha As Double = ((degree - 90) / 180) * PI Dim iHeight As Integer = img.Width * Math.Cos(alpha) + img.Height * Math.Sin(alpha) Dim iWidth As Integer = img.Width * Math.Sin(alpha) + img.Height * Math.Cos(alpha) ImgTarget = New Bitmap(iWidth, iHeight, Drawing.Imaging.PixelFormat.Format24bppRgb) Dim g As Graphics g = Graphics.FromImage(ImgTarget) g.TranslateTransform(iWidth, img.Height * Math.Sin(alpha)) g.RotateTransform(degree) g.DrawImage(img, New Rectangle(0, 0, img.Width, img.Height)) Return ImgTarget End Function Private Function Rotate180_270(ByVal img As Image, ByVal degree As Integer) As Image Dim ImgTarget As Bitmap Dim alpha As Double = ((degree - 180) / 180) * PI Dim iWidth As Integer = img.Width * Math.Cos(alpha) + img.Height * Math.Sin(alpha) Dim iHeight As Integer = img.Width * Math.Sin(alpha) + img.Height * Math.Cos(alpha) ImgTarget = New Bitmap(iWidth, iHeight, Drawing.Imaging.PixelFormat.Format24bppRgb) Dim g As Graphics g = Graphics.FromImage(ImgTarget) g.TranslateTransform(img.Width * Math.Cos(alpha), iHeight) g.RotateTransform(degree) g.DrawImage(img, New Rectangle(0, 0, img.Width, img.Height)) Return ImgTarget End Function Private Function Rotate270_360(ByVal img As Image, ByVal degree As Integer) As Image Dim ImgTarget As Bitmap Dim alpha As Double = ((degree - 270) / 180) * PI Dim iHeight As Integer = img.Width * Math.Cos(alpha) + img.Height * Math.Sin(alpha) Dim iWidth As Integer = img.Width * Math.Sin(alpha) + img.Height * Math.Cos(alpha) ImgTarget = New Bitmap(iWidth, iHeight, Drawing.Imaging.PixelFormat.Format24bppRgb) Dim g As Graphics g = Graphics.FromImage(ImgTarget) g.TranslateTransform(0, img.Width * Math.Cos(alpha)) g.RotateTransform(degree) g.DrawImage(img, New Rectangle(0, 0, img.Width, img.Height)) Return ImgTarget End Function End Class
04	如何執行TextBox裏的運算式?
	Public Class Form1 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load TextBox1.Text = "100 + (200 + 300) /100" Dim sc = CreateObject("ScriptControl") sc.language = "VBscript" MsgBox(sc.eval(TextBox1.Text)) sc = Nothing End Sub End Class
03	如何取得所有執行中的程序?
	Public Class Form1 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load For Each i As Process In Process.GetProcesses '取得所有執行中的程序 Debug.Print(i.ProcessName & vbTab & i.Id) 'If i.ProcessName = "notepad" Then i.Kill() '如果有筆記本則關閉它 Next End Sub End Class
02	如何抓當下座標的背景顏色?
	Public Class Form1 Dim g As Graphics, b As Bitmap Private Sub PictureBox1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseMove b = PictureBox1.BackgroundImage Debug.Print(Hex(b.GetPixel(e.X, e.Y).R) & " " & Hex(b.GetPixel(e.X, e.Y).G) & " " & Hex(b.GetPixel(e.X, e.Y).B)) End Sub Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseMove b = Me.BackgroundImage Debug.Print(Hex(b.GetPixel(e.X, e.Y).R) & " " & Hex(b.GetPixel(e.X, e.Y).G) & " " & Hex(b.GetPixel(e.X, e.Y).B)) End Sub 　 '以下純為畫一些東東好測試...套用時請自忽略~ Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load PictureBox1.BackColor = Color.Black : PictureBox1.Location = New Point(100, 100) PictureBox1.Size = New Size(100, 100) : PictureBox1.BackgroundImage = New Bitmap(100, 100) g = System.Drawing.Graphics.FromImage(PictureBox1.BackgroundImage) g.DrawLine(Pens.Blue, 0, 0, 50, 50) : g.DrawLine(Pens.Red, 100, 0, 0, 100) Me.BackgroundImage = New Bitmap(1024, 768) g = System.Drawing.Graphics.FromImage(Me.BackgroundImage) g.FillRectangle(Brushes.Yellow, New Rectangle(0, 0, 100, 100)) g.FillRectangle(Brushes.Green, New Rectangle(0, 0, 50, 50)) End Sub End Class
01	撲克牌亂數發牌-含花色
	Public Class Form1 Dim poker(0 To 51) As String Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim i As Integer For i = 0 To 51 : poker(i) = ((i Mod 13 + 1) & Mid("♠♣♥♦", (i \ 13) + 1, 1)) : Next Randomize() For i = 1 To 100 : swap(Int(Rnd() * 52), Int(Rnd() * 52)) : Next For i = 1 To 4 : Me.Controls("textbox" & i).Text = "" : Next For i = 0 To 51 : Me.Controls("textbox" & (i \ 13) + 1).Text += poker(i) & IIf(poker(i).Length = 2, " ", " ") : Next For i = 1 To 4 : Debug.Print(Me.Controls("textbox" & i).Text) : Next End Sub Sub swap(ByVal p1, ByVal p2) Dim t As String = poker(p1) poker(p1) = poker(p2) : poker(p2) = t End Sub End Class 　結果: 12♦ 11♦ 6♣ 1♣ 13♠ 3♦ 9♠ 10♥ 4♣ 10♠ 8♠ 5♦ 5♣ 3♥ 9♦ 3♠ 7♠ 3♣ 4♠ 12♣ 13♣ 10♦ 1♠ 8♦ 2♦ 12♠ 7♦ 4♥ 9♣ 2♣ 6♦ 10♣ 12♥ 7♥ 6♥ 11♣ 2♥ 5♥ 13♦ 11♠ 11♥ 4♦ 7♣ 1♦ 6♠ 13♥ 9♥ 8♥ 2♠ 8♣ 1♥ 5♠