Beispiel #1
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        public static IntPtr ExtCreatePen(int fnStyle, int dwWidth, IntNativeMethods.LOGBRUSH lplb, int dwStyleCount, int[] lpStyle)
        {
            IntPtr hPen = System.Internal.HandleCollector.Add(IntExtCreatePen(fnStyle, dwWidth, lplb, dwStyleCount, lpStyle), IntSafeNativeMethods.CommonHandles.GDI);

            DbgUtil.AssertWin32(hPen != IntPtr.Zero, "IntExtCreatePen(style={0}, width={1}, brush={2}, styleCount={3}, styles={4}) failed.", fnStyle, dwWidth, lplb, dwStyleCount, lpStyle);
            return(hPen);
        }
Beispiel #2
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        public static IntPtr CreateRectRgn(int x1, int y1, int x2, int y2)
        {
            IntPtr hRgn = System.Internal.HandleCollector.Add(IntCreateRectRgn(x1, y1, x2, y2), CommonHandles.GDI);

            DbgUtil.AssertWin32(hRgn != IntPtr.Zero, "IntCreateRectRgn([x1={0}, y1={1}, x2={2}, y2={3}]) failed.", x1, y1, x2, y2);
            return(hRgn);
        }
Beispiel #3
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        public static IntPtr CreatePen(int fnStyle, int nWidth, int crColor)
        {
            IntPtr hPen = System.Internal.HandleCollector.Add(IntCreatePen(fnStyle, nWidth, crColor), IntSafeNativeMethods.CommonHandles.GDI);

            DbgUtil.AssertWin32(hPen != IntPtr.Zero, "IntCreatePen(style={0}, width={1}, color=[{2}]) failed.", fnStyle, nWidth, crColor);
            return(hPen);
        }
Beispiel #4
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        public static IntPtr CreateSolidBrush(int crColor)
        {
            IntPtr hBrush = System.Internal.HandleCollector.Add(IntCreateSolidBrush(crColor), IntSafeNativeMethods.CommonHandles.GDI);

            DbgUtil.AssertWin32(hBrush != IntPtr.Zero, "IntCreateSolidBrush(color={0}) failed.", crColor);
            return(hBrush);
        }
Beispiel #5
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        /// <summary>
        /// Saves the current state of the device context by copying data describing selected objects and graphic
        /// modes (such as the bitmap, brush, palette, font, pen, region, drawing mode, and mapping mode) to a
        /// context stack.
        /// The SaveDC function can be used any number of times to save any number of instances of the DC state.
        /// A saved state can be restored by using the RestoreHdc method.
        /// See MSDN for more details.
        /// </summary>
        public int SaveHdc()
        {
            HandleRef hdc   = new HandleRef(this, _hDC);
            int       state = Interop.Gdi32.SaveDC(hdc);

            if (_contextStack == null)
            {
                _contextStack = new Stack();
            }

            GraphicsState g = new GraphicsState();

            g.hBitmap = _hCurrentBmp;
            g.hBrush  = _hCurrentBrush;
            g.hPen    = _hCurrentPen;
            g.hFont   = _hCurrentFont;

            _contextStack.Push(g);

#if TRACK_HDC
            Debug.WriteLine(DbgUtil.StackTraceToStr(string.Format("state[0]=DC.SaveHdc(hDc=0x{1:x8})", state, unchecked ((int)_hDC))));
#endif

            return(state);
        }
Beispiel #6
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        /// <summary>
        /// Restores the device context to the specified state. The DC is restored by popping state information off a
        /// stack created by earlier calls to the SaveHdc function.
        /// The stack can contain the state information for several instances of the DC. If the state specified by the
        /// specified parameter is not at the top of the stack, RestoreDC deletes all state information between the top
        /// of the stack and the specified instance.
        /// Specifies the saved state to be restored. If this parameter is positive, nSavedDC represents a specific
        /// instance of the state to be restored. If this parameter is negative, nSavedDC represents an instance relative
        /// to the current state. For example, -1 restores the most recently saved state.
        /// See MSDN for more info.
        /// </summary>
        public void RestoreHdc()
        {
#if TRACK_HDC
            bool result =
#endif
            // Note: Don't use the Hdc property here, it would force handle creation.
            Interop.Gdi32.RestoreDC(new HandleRef(this, _hDC), -1);
#if TRACK_HDC
            // Note: Winforms may call this method during app exit at which point the DC may have been finalized already causing this assert to popup.
            Debug.WriteLine(DbgUtil.StackTraceToStr(string.Format("ret[0]=DC.RestoreHdc(hDc=0x{1:x8}, state={2})", result, unchecked ((int)_hDC), restoreState)));
#endif
            Debug.Assert(_contextStack != null, "Someone is calling RestoreHdc() before SaveHdc()");

            if (_contextStack != null)
            {
                GraphicsState g = (GraphicsState)_contextStack.Pop() !;

                _hCurrentBmp   = g.hBitmap;
                _hCurrentBrush = g.hBrush;
                _hCurrentPen   = g.hPen;
                _hCurrentFont  = g.hFont;
            }

#if OPTIMIZED_MEASUREMENTDC
            // in this case, GDI will copy back the previously saved font into the DC.
            // we dont actually know what the font is in our measurement DC so
            // we need to clear it off.
            MeasurementDCInfo.ResetIfIsMeasurementDC(_hDC);
#endif
        }
        internal void Dispose(bool disposing)
        {
            if (_dc != null)
            {
                DbgUtil.AssertFinalization(this, disposing);

                try
                {
                    // Restore original dc.
                    _dc.RestoreHdc();

                    if (_disposeDc)
                    {
                        _dc.Dispose(disposing);
                    }

                    if (_graphics != null)    // if created from a Graphics object...
                    {
                        _graphics.ReleaseHdcInternal(_dc.Hdc);
                        _graphics = null;
                    }
                }
                catch (Exception ex) when(!ClientUtils.IsSecurityOrCriticalException(ex))
                {
                    Debug.Fail("Exception thrown during disposing: \r\n" + ex.ToString());
                }
                finally
                {
                    _dc = null !;
                }
            }
        }
Beispiel #8
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        public static bool DeleteObject(HandleRef hObject)
        {
            System.Internal.HandleCollector.Remove((IntPtr)hObject, IntSafeNativeMethods.CommonHandles.GDI);
            bool retVal = IntDeleteObject(hObject);

            DbgUtil.AssertWin32(retVal, "DeleteObject(hObj=[0x{0:X8}]) failed.", hObject.Handle);
            return(retVal);
        }
Beispiel #9
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        public static int GetTextExtentPoint32(HandleRef hDC, string text, [In, Out] IntNativeMethods.SIZE size)
        {
            int byteCount = text.Length;
            int retVal    = GetTextExtentPoint32W(hDC, text, text.Length, size);

            DbgUtil.AssertWin32(retVal != 0, "GetTextExtentPoint32(hdc=[0x{0:X8}], text=[{1}], size=[{2}] failed.", hDC.Handle, text, size);
            return(retVal);
        }
Beispiel #10
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        public static IntPtr GetCurrentObject(HandleRef hDC, int uObjectType)
        {
            IntPtr hGdiObj = IntGetCurrentObject(hDC, uObjectType);

            // If the selected object is a region the return value is HGI_ERROR on failure.
            DbgUtil.AssertWin32(hGdiObj != IntPtr.Zero, "GetObject(hdc=[0x{0:X8}], type=[{1}]) failed.", hDC, uObjectType);
            return(hGdiObj);
        }
Beispiel #11
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        public static bool DeleteHDC(HandleRef hDC)
        {
            System.Internal.HandleCollector.Remove((IntPtr)hDC, IntSafeNativeMethods.CommonHandles.HDC);
            bool retVal = IntDeleteDC(hDC);

            DbgUtil.AssertWin32(retVal, "DeleteHDC([hdc=0x{0:X8}]) failed.", hDC.Handle);
            return(retVal);
        }
Beispiel #12
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        /// <include file='doc\IDeviceContext.uex' path='docs/doc[@for="DeviceContext.Dispose1"]/*' />
        internal void Dispose(bool disposing)
        {
            if (_disposed)
            {
                return;
            }

            if (Disposing != null)
            {
                Disposing(this, EventArgs.Empty);
            }

            _disposed = true;

            switch (_dcType)
            {
            case DeviceContextType.Display:
                Debug.Assert(disposing, "WARNING: Finalizing a Display DeviceContext.\r\nReleaseDC may fail when not called from the same thread GetDC was called from.");

                ((IDeviceContext)this).ReleaseHdc();
                break;

            case DeviceContextType.Information:
            case DeviceContextType.NamedDevice:

                // CreateDC and CreateIC add an HDC handle to the HandleCollector; to remove it properly we need
                // to call DeleteHDC.
#if TRACK_HDC
                Debug.WriteLine(DbgUtil.StackTraceToStr(String.Format("DC.DeleteHDC(hdc=0x{0:x8})", unchecked ((int)_hDC))));
#endif

                IntUnsafeNativeMethods.DeleteHDC(new HandleRef(this, _hDC));

                _hDC = IntPtr.Zero;
                break;

            case DeviceContextType.Memory:

                // CreatCompatibleDC adds a GDI handle to HandleCollector, to remove it properly we need to call
                // DeleteDC.
#if TRACK_HDC
                Debug.WriteLine(DbgUtil.StackTraceToStr(String.Format("DC.DeleteDC(hdc=0x{0:x8})", unchecked ((int)_hDC))));
#endif
                IntUnsafeNativeMethods.DeleteDC(new HandleRef(this, _hDC));

                _hDC = IntPtr.Zero;
                break;

            // case DeviceContextType.Metafile: - not yet supported.
            case DeviceContextType.Unknown:
            default:
                return;
                // do nothing, the hdc is not owned by this object.
                // in this case it is ok if disposed throught finalization.
            }

            DbgUtil.AssertFinalization(this, disposing);
        }
Beispiel #13
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        public static void AssertWin32(bool expression, string message)
        {
#if DEBUG
            if (!expression)
            {
                Debug.Fail(message + "\r\nError: " + DbgUtil.GetLastErrorStr());
            }
#endif
        }
Beispiel #14
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        [Conditional("DEBUG")] // This code will be compiled into the assembly anyways, it is up to the compiler to ignore the call.
        private static void AssertWin32Impl(bool expression, string format, object[] args)
        {
#if DEBUG
            if (!expression)
            {
                string message = string.Format(CultureInfo.CurrentCulture, format, args);
                Debug.Fail(message + "\r\nError: " + DbgUtil.GetLastErrorStr());
            }
#endif
        }
Beispiel #15
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        /// <summary>
        /// Constructor to construct a DeviceContext object from an existing Win32 device context handle.
        /// </summary>
        private DeviceContext(IntPtr hDC, DeviceContextType dcType)
        {
            _hDC    = hDC;
            _dcType = dcType;

            CacheInitialState();
            DeviceContexts.AddDeviceContext(this);

#if TRACK_HDC
            Debug.WriteLine(DbgUtil.StackTraceToStr($"DeviceContext(hDC=0x{(int)hDC:X8}, Type={dcType})"));
#endif
        }
Beispiel #16
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        /// <summary>
        /// Constructor to construct a DeviceContext object from an window handle.
        /// </summary>
        private DeviceContext(IntPtr hWnd)
        {
            _hWnd   = hWnd;
            _dcType = DeviceContextType.Display;

            DeviceContexts.AddDeviceContext(this);

            // the hDc will be created on demand.

#if TRACK_HDC
            Debug.WriteLine(DbgUtil.StackTraceToStr(string.Format("DeviceContext( hWnd=0x{0:x8} )", unchecked ((int)hWnd))));
#endif
        }
Beispiel #17
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        ///<summary>
        /// If the object was created from a DC, this object doesn't 'own' the dc so we just ignore this call.
        ///</summary>
        void IDeviceContext.ReleaseHdc()
        {
            if (_hDC != IntPtr.Zero && _dcType == DeviceContextType.Display)
            {
#if TRACK_HDC
                int retVal =
#endif
                IntUnsafeNativeMethods.ReleaseDC(new HandleRef(this, _hWnd), new HandleRef(this, _hDC));
                // Note: retVal == 0 means it was not released but doesn't necessarily means an error; class or private DCs are never released.
#if TRACK_HDC
                Debug.WriteLine(DbgUtil.StackTraceToStr(string.Format("[ret={0}]=DC.ReleaseDC(hDc=0x{1:x8}, hWnd=0x{2:x8})", retVal, unchecked ((int)_hDC), unchecked ((int)_hWnd))));
#endif
                _hDC = IntPtr.Zero;
            }
        }
Beispiel #18
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        /// <summary>
        /// Constructor to construct a DeviceContext object from an existing Win32 device context handle.
        /// </summary>
        private DeviceContext(IntPtr hDC, DeviceContextType dcType)
        {
            _hDC    = hDC;
            _dcType = dcType;

            CacheInitialState();
            DeviceContexts.AddDeviceContext(this);

            if (dcType == DeviceContextType.Display)
            {
                _hWnd = IntUnsafeNativeMethods.WindowFromDC(new HandleRef(this, _hDC));
            }
#if TRACK_HDC
            Debug.WriteLine(DbgUtil.StackTraceToStr(string.Format("DeviceContext( hDC=0x{0:X8}, Type={1} )", unchecked ((int)hDC), dcType)));
#endif
        }
Beispiel #19
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        /// <summary>
        /// Constructor to construct a DeviceContext object from an existing Win32 device context handle.
        /// </summary>
        private DeviceContext(IntPtr hDC, DeviceContextType dcType)
        {
            _hDC    = hDC;
            _dcType = dcType;

            CacheInitialState();
            DeviceContexts.AddDeviceContext(this);

            if (dcType == DeviceContextType.Display)
            {
                _hWnd = Interop.User32.WindowFromDC(new HandleRef(this, _hDC));
            }
#if TRACK_HDC
            Debug.WriteLine(DbgUtil.StackTraceToStr($"DeviceContext(hDC=0x{(int)hDC:X8}, Type={dcType})"));
#endif
        }
Beispiel #20
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        /// <summary>
        /// Explicit interface method implementation to hide them a bit for usability reasons so the object is seen as
        /// a wrapper around an hdc that is always available, and for performance reasons since it caches the hdc if
        /// used in this way.
        /// </summary>
        IntPtr IDeviceContext.GetHdc()
        {
            if (_hDC == IntPtr.Zero)
            {
                Debug.Assert(_dcType == DeviceContextType.Display, "Calling GetDC from a non display/window device.");

                // Note: for common DCs, GetDC assigns default attributes to the DC each time it is retrieved.
                // For example, the default font is System.
                _hDC = IntUnsafeNativeMethods.GetDC(new HandleRef(this, _hWnd));
#if TRACK_HDC
                Debug.WriteLine(DbgUtil.StackTraceToStr(string.Format("hdc[0x{0:x8}]=DC.GetHdc(hWnd=0x{1:x8})", unchecked ((int)_hDC), unchecked ((int)_hWnd))));
#endif
            }

            return(_hDC);
        }
Beispiel #21
0
        public static bool Arc(
            HandleRef hDC,
            int nLeftRect,   // x-coord of rectangle's upper-left corner
            int nTopRect,    // y-coord of rectangle's upper-left corner
            int nRightRect,  // x-coord of rectangle's lower-right corner
            int nBottomRect, // y-coord of rectangle's lower-right corner
            int nXStartArc,  // x-coord of first radial ending point
            int nYStartArc,  // y-coord of first radial ending point
            int nXEndArc,    // x-coord of second radial ending point
            int nYEndArc     // y-coord of second radial ending point
            )
        {
            bool retVal = IntArc(hDC, nLeftRect, nTopRect, nRightRect, nBottomRect, nXStartArc, nYStartArc, nXEndArc, nYEndArc);

            DbgUtil.AssertWin32(retVal, "Arc(hdc=[0x{0:X8}], ...) failed.", hDC.Handle);
            return(retVal);
        }
Beispiel #22
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        public void Dispose(bool disposing)
        {
            if (_nativeHandle != IntPtr.Zero)
            {
                DbgUtil.AssertFinalization(this, disposing);

                if (_ownHandle)
                {
                    IntUnsafeNativeMethods.DeleteObject(new HandleRef(this, _nativeHandle));
                }

                _nativeHandle = IntPtr.Zero;

                if (disposing)
                {
                    GC.SuppressFinalize(this);
                }
            }
        }
Beispiel #23
0
        public static int GetTextMetrics(HandleRef hDC, ref IntNativeMethods.TEXTMETRIC lptm)
        {
            int retVal;

            if (Marshal.SystemDefaultCharSize == 1)
            {
                // ANSI
                IntNativeMethods.TEXTMETRICA lptmA = new IntNativeMethods.TEXTMETRICA();
                retVal = IntUnsafeNativeMethods.GetTextMetricsA(hDC, ref lptmA);

                lptm.tmHeight           = lptmA.tmHeight;
                lptm.tmAscent           = lptmA.tmAscent;
                lptm.tmDescent          = lptmA.tmDescent;
                lptm.tmInternalLeading  = lptmA.tmInternalLeading;
                lptm.tmExternalLeading  = lptmA.tmExternalLeading;
                lptm.tmAveCharWidth     = lptmA.tmAveCharWidth;
                lptm.tmMaxCharWidth     = lptmA.tmMaxCharWidth;
                lptm.tmWeight           = lptmA.tmWeight;
                lptm.tmOverhang         = lptmA.tmOverhang;
                lptm.tmDigitizedAspectX = lptmA.tmDigitizedAspectX;
                lptm.tmDigitizedAspectY = lptmA.tmDigitizedAspectY;
                lptm.tmFirstChar        = (char)lptmA.tmFirstChar;
                lptm.tmLastChar         = (char)lptmA.tmLastChar;
                lptm.tmDefaultChar      = (char)lptmA.tmDefaultChar;
                lptm.tmBreakChar        = (char)lptmA.tmBreakChar;
                lptm.tmItalic           = lptmA.tmItalic;
                lptm.tmUnderlined       = lptmA.tmUnderlined;
                lptm.tmStruckOut        = lptmA.tmStruckOut;
                lptm.tmPitchAndFamily   = lptmA.tmPitchAndFamily;
                lptm.tmCharSet          = lptmA.tmCharSet;
            }
            else
            {
                // Unicode
                retVal = IntUnsafeNativeMethods.GetTextMetricsW(hDC, ref lptm);
            }

            DbgUtil.AssertWin32(retVal != 0, "GetTextMetrics(hdc=[0x{0:X8}], [out TEXTMETRIC] failed.", hDC.Handle);
            return(retVal);
        }
Beispiel #24
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        internal void Dispose(bool disposing)
        {
            if (_disposed)
            {
                return;
            }

            Disposing?.Invoke(this, EventArgs.Empty);

            _disposed = true;

            switch (_dcType)
            {
            case DeviceContextType.Display:
                Debug.Assert(disposing, "WARNING: Finalizing a Display DeviceContext.\r\nReleaseDC may fail when not called from the same thread GetDC was called from.");
                ((IDeviceContext)this).ReleaseHdc();
                break;

            case DeviceContextType.Information:
            case DeviceContextType.NamedDevice:
                Interop.Gdi32.DeleteDC(new HandleRef(this, _hDC));
                _hDC = IntPtr.Zero;
                break;

            case DeviceContextType.Memory:
                Interop.Gdi32.DeleteDC(new HandleRef(this, _hDC));
                _hDC = IntPtr.Zero;
                break;

            // case DeviceContextType.Metafile: - not yet supported.
            case DeviceContextType.Unknown:
            default:
                return;
                // do nothing, the hdc is not owned by this object.
                // in this case it is ok if disposed throught finalization.
            }

            DbgUtil.AssertFinalization(this, disposing);
        }
Beispiel #25
0
        public static int GetTextExtentPoint32(HandleRef hDC, string text, [In, Out] IntNativeMethods.SIZE size)
        {
            int retVal;
            int byteCount = text.Length;

            if (Marshal.SystemDefaultCharSize == 1)
            {
                // Convert Unicode string to ANSI.
                byteCount = IntUnsafeNativeMethods.WideCharToMultiByte(IntNativeMethods.CP_ACP, 0, text, text.Length, null, 0, IntPtr.Zero, IntPtr.Zero);
                byte[] textBytes = new byte[byteCount];
                IntUnsafeNativeMethods.WideCharToMultiByte(IntNativeMethods.CP_ACP, 0, text, text.Length, textBytes, textBytes.Length, IntPtr.Zero, IntPtr.Zero);

                // Security: Windows 95/98/Me: This value may not exceed 8192.
                byteCount = Math.Min(text.Length, IntNativeMethods.MaxTextLengthInWin9x);
                retVal    = GetTextExtentPoint32A(hDC, textBytes, byteCount, size);
            }
            else
            {
                retVal = GetTextExtentPoint32W(hDC, text, text.Length, size);
            }

            DbgUtil.AssertWin32(retVal != 0, "GetTextExtentPoint32(hdc=[0x{0:X8}], text=[{1}], size=[{2}] failed.", hDC.Handle, text, size);
            return(retVal);
        }
Beispiel #26
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        /// <devdoc>
        ///   Returns information about the top stack frames in a string format.  The input param determines the number of
        ///   frames to include.
        /// </devdoc>
        public static string StackFramesToStr(int maxFrameCount)
        {
            string trace = String.Empty;

            try
            {
                StackTrace st = new StackTrace(true);
                int        dbgUtilFrameCount = 0;

                //
                // Ignore frames for methods on this library.
                // Note: The stack frame holds the latest frame at index 0.
                //
                while (dbgUtilFrameCount < st.FrameCount)
                {
                    StackFrame sf = st.GetFrame(dbgUtilFrameCount);

                    if (sf == null || sf.GetMethod().DeclaringType != typeof(DbgUtil))
                    {
                        break;
                    }

                    dbgUtilFrameCount++;
                }

                maxFrameCount += dbgUtilFrameCount; // add ignored frames.

                if (maxFrameCount > st.FrameCount)
                {
                    maxFrameCount = st.FrameCount;
                }

                for (int i = dbgUtilFrameCount; i < maxFrameCount; i++)
                {
                    StackFrame sf = st.GetFrame(i);

                    if (sf == null)
                    {
                        continue;
                    }

                    MethodBase mi = sf.GetMethod();

                    if (mi == null)
                    {
                        continue;
                    }

                    string args     = String.Empty;
                    string fileName = sf.GetFileName();

                    int backSlashIndex = fileName == null ? -1 : fileName.LastIndexOf('\\');

                    if (backSlashIndex != -1)
                    {
                        fileName = fileName.Substring(backSlashIndex + 1, fileName.Length - backSlashIndex - 1);
                    }

                    foreach (ParameterInfo pi in mi.GetParameters())
                    {
                        args += pi.ParameterType.Name + ", ";
                    }

                    if (args.Length > 0)   // remove last comma.
                    {
                        args = args.Substring(0, args.Length - 2);
                    }

                    trace += String.Format(CultureInfo.CurrentCulture, "at {0} {1}.{2}({3})\r\n", fileName, mi.DeclaringType, mi.Name, args);
                }
            }
            catch (Exception ex)
            {
                if (DbgUtil.IsCriticalException(ex))
                {
                    throw;  //rethrow critical exception.
                }
                trace += ex.ToString();
            }

            return(trace.ToString());
        }
Beispiel #27
0
 /// <devdoc>
 ///   Returns information about the top stack frames in a string format.  The input param determines the number of
 ///   frames to include.  The 'message' parameter is used as the header of the returned string.
 /// </devdoc>
 public static string StackTraceToStr(string message, int frameCount)
 {
     return(String.Format(CultureInfo.CurrentCulture, "{0}\r\nTop Stack Trace:\r\n{1}", message, DbgUtil.StackFramesToStr(frameCount)));
 }
Beispiel #28
0
 public static int SetGraphicsMode(HandleRef hDC, int iMode)
 {
     iMode = IntSetGraphicsMode(hDC, iMode);
     DbgUtil.AssertWin32(iMode != 0, "SetGraphicsMode([hdc=0x{0:X8}], [GM_ADVANCED]) failed.", hDC.Handle);
     return(iMode);
 }
Beispiel #29
0
 public static IntNativeMethods.RegionFlags SelectClipRgn(HandleRef hDC, HandleRef hRgn)
 {
     IntNativeMethods.RegionFlags result = IntSelectClipRgn(hDC, hRgn);
     DbgUtil.AssertWin32(result != IntNativeMethods.RegionFlags.ERROR, "SelectClipRgn([hdc=0x{0:X8}], [hRegion=0x{1:X8}]) failed.", hDC.Handle, hRgn.Handle);
     return(result);
 }
Beispiel #30
0
 public static IntNativeMethods.RegionFlags GetRgnBox(HandleRef hRgn, [In, Out] ref IntNativeMethods.RECT clipRect)
 {
     IntNativeMethods.RegionFlags result = IntGetRgnBox(hRgn, ref clipRect);
     DbgUtil.AssertWin32(result != IntNativeMethods.RegionFlags.ERROR, "GetRgnBox([hRegion=0x{0:X8}], [out rect]) failed.", hRgn.Handle);
     return(result);
 }