49 lines
1.4 KiB
VB.net
49 lines
1.4 KiB
VB.net
Imports System.Runtime.CompilerServices
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Imports System.Windows.Forms
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Namespace Utils
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Public Module DrawingControl
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Private Const WM_SETREDRAW = 11
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Private ReadOnly dicSuspendCount As New Dictionary(Of IntPtr, Integer)
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<Extension>
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Public Sub SuspendDrawing(control As Control)
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If Not dicSuspendCount.ContainsKey(control.Handle) Then
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dicSuspendCount.Add(control.Handle, 1)
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Else
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dicSuspendCount(control.Handle) += 1
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End If
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If dicSuspendCount(control.Handle) = 1 Then
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SendMessage(control.Handle, WM_SETREDRAW, False, 0)
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End If
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End Sub
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<Extension>
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Public Sub ResumeDrawing(control As Control)
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ResumeDrawing(control, True)
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End Sub
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<Extension>
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Public Sub ResumeDrawing(control As Control, redraw As Boolean)
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Dim doRedraw As Boolean = True
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If dicSuspendCount.ContainsKey(control.Handle) Then
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dicSuspendCount(control.Handle) -= 1
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If dicSuspendCount(control.Handle) >= 1 Then
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doRedraw = False
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End If
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End If
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If doRedraw Then
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SendMessage(control.Handle, WM_SETREDRAW, True, 0)
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If redraw Then control.Refresh()
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End If
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End Sub
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End Module
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End Namespace
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