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//------------------------------------------------------------------------------
// <copyright file="PreviewPrintController.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
namespace System.Drawing.Printing {
using Microsoft.Win32;
using System;
using System.Collections;
using System.ComponentModel;
using System.Diagnostics;
using System.Drawing;
using System.Drawing.Internal;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Drawing.Text;
using System.Runtime.InteropServices;
using System.Runtime.Versioning;
using CodeAccessPermission = System.Security.CodeAccessPermission;
/// <include file='doc\PreviewPrintController.uex' path='docs/doc[@for="PreviewPrintController"]/*' />
/// <devdoc>
/// A PrintController which "prints" to a series of images.
/// </devdoc>
public class PreviewPrintController : PrintController {
private IList list = new ArrayList(); // list of PreviewPageInfo
private System.Drawing.Graphics graphics;
private DeviceContext dc;
private bool antiAlias;
private void CheckSecurity() {
IntSecurity.SafePrinting.Demand();
}
/// <include file='doc\PreviewPrintController.uex' path='docs/doc[@for="PreviewPrintController.IsPreview"]/*' />
/// <devdoc>
/// <para>
/// This is new public property which notifies if this controller is used for PrintPreview.
/// </para>
/// </devdoc>
public override bool IsPreview {
get {
return true;
}
}
/// <include file='doc\PreviewPrintController.uex' path='docs/doc[@for="PreviewPrintController.OnStartPrint"]/*' />
/// <devdoc>
/// <para>
/// Implements StartPrint for generating print preview information.
/// </para>
/// </devdoc>
[ResourceExposure(ResourceScope.Process)]
[ResourceConsumption(ResourceScope.Process)]
public override void OnStartPrint(PrintDocument document, PrintEventArgs e) {
Debug.Assert(dc == null && graphics == null, "PrintController methods called in the wrong order?");
// For security purposes, don't assume our public methods methods are called in any particular order
CheckSecurity();
base.OnStartPrint(document, e);
try {
if (!document.PrinterSettings.IsValid)
throw new InvalidPrinterException(document.PrinterSettings);
IntSecurity.AllPrintingAndUnmanagedCode.Assert();
// We need a DC as a reference; we don't actually draw on it.
// We make sure to reuse the same one to improve performance.
dc = document.PrinterSettings.CreateInformationContext(modeHandle);
}
finally {
CodeAccessPermission.RevertAssert();
}
}
/// <include file='doc\PreviewPrintController.uex' path='docs/doc[@for="PreviewPrintController.OnStartPage"]/*' />
/// <devdoc>
/// <para>
/// Implements StartEnd for generating print preview information.
/// </para>
/// </devdoc>
[ResourceExposure(ResourceScope.Process)]
[ResourceConsumption(ResourceScope.Machine | ResourceScope.Process, ResourceScope.Machine)]
public override Graphics OnStartPage(PrintDocument document, PrintPageEventArgs e) {
Debug.Assert(dc != null && graphics == null, "PrintController methods called in the wrong order?");
// For security purposes, don't assume our public methods methods are called in any particular order
CheckSecurity();
base.OnStartPage(document, e);
try {
IntSecurity.AllPrintingAndUnmanagedCode.Assert();
if (e.CopySettingsToDevMode) {
e.PageSettings.CopyToHdevmode(modeHandle);
}
Size size = e.PageBounds.Size;
// Metafile framing rectangles apparently use hundredths of mm as their unit of measurement,
// instead of the GDI+ standard hundredth of an inch.
Size metafileSize = PrinterUnitConvert.Convert(size, PrinterUnit.Display, PrinterUnit.HundredthsOfAMillimeter);
// Create a Metafile which accepts only GDI+ commands since we are the ones creating
// and using this ...
// Framework creates a dual-mode EMF for each page in the preview.
// When these images are displayed in preview,
// they are added to the dual-mode EMF. However,
// GDI+ breaks during this process if the image
// is sufficiently large and has more than 254 colors.
// This code path can easily be avoided by requesting
// an EmfPlusOnly EMF..
Metafile metafile = new Metafile(dc.Hdc, new Rectangle(0,0, metafileSize.Width, metafileSize.Height), MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusOnly);
PreviewPageInfo info = new PreviewPageInfo(metafile, size);
list.Add(info);
PrintPreviewGraphics printGraphics = new PrintPreviewGraphics(document, e);
graphics = Graphics.FromImage(metafile);
if (graphics != null && document.OriginAtMargins) {
// Adjust the origin of the graphics object to be at the
// user-specified margin location
//
int dpiX = UnsafeNativeMethods.GetDeviceCaps(new HandleRef(dc, dc.Hdc), SafeNativeMethods.LOGPIXELSX);
int dpiY = UnsafeNativeMethods.GetDeviceCaps(new HandleRef(dc, dc.Hdc), SafeNativeMethods.LOGPIXELSY);
int hardMarginX_DU = UnsafeNativeMethods.GetDeviceCaps(new HandleRef(dc, dc.Hdc), SafeNativeMethods.PHYSICALOFFSETX);
int hardMarginY_DU = UnsafeNativeMethods.GetDeviceCaps(new HandleRef(dc, dc.Hdc), SafeNativeMethods.PHYSICALOFFSETY);
float hardMarginX = hardMarginX_DU * 100 / dpiX;
float hardMarginY = hardMarginY_DU * 100 / dpiY;
graphics.TranslateTransform(-hardMarginX, -hardMarginY);
graphics.TranslateTransform(document.DefaultPageSettings.Margins.Left, document.DefaultPageSettings.Margins.Top);
}
graphics.PrintingHelper = printGraphics;
if (antiAlias) {
graphics.TextRenderingHint = TextRenderingHint.AntiAlias;
graphics.SmoothingMode = SmoothingMode.AntiAlias;
}
}
finally {
CodeAccessPermission.RevertAssert();
}
return graphics;
}
/// <include file='doc\PreviewPrintController.uex' path='docs/doc[@for="PreviewPrintController.OnEndPage"]/*' />
/// <devdoc>
/// <para>
/// Implements EndPage for generating print preview information.
/// </para>
/// </devdoc>
public override void OnEndPage(PrintDocument document, PrintPageEventArgs e) {
Debug.Assert(dc != null && graphics != null, "PrintController methods called in the wrong order?");
// For security purposes, don't assume our public methods methods are called in any particular order
CheckSecurity();
graphics.Dispose();
graphics = null;
base.OnEndPage(document, e);
}
/// <include file='doc\PreviewPrintController.uex' path='docs/doc[@for="PreviewPrintController.OnEndPrint"]/*' />
/// <devdoc>
/// <para>
/// Implements EndPrint for generating print preview information.
/// </para>
/// </devdoc>
public override void OnEndPrint(PrintDocument document, PrintEventArgs e) {
Debug.Assert(dc != null && graphics == null, "PrintController methods called in the wrong order?");
// For security purposes, don't assume our public methods are called in any particular order
CheckSecurity();
dc.Dispose();
dc = null;
base.OnEndPrint(document, e);
}
/// <include file='doc\PreviewPrintController.uex' path='docs/doc[@for="PreviewPrintController.GetPreviewPageInfo"]/*' />
/// <devdoc>
/// <para>
/// The "printout".
/// </para>
/// </devdoc>
public PreviewPageInfo[] GetPreviewPageInfo() {
// For security purposes, don't assume our public methods methods are called in any particular order
CheckSecurity();
PreviewPageInfo[] temp = new PreviewPageInfo[list.Count];
list.CopyTo(temp, 0);
return temp;
}
/// <include file='doc\PreviewPrintController.uex' path='docs/doc[@for="PreviewPrintController.UseAntiAlias"]/*' />
public virtual bool UseAntiAlias {
get {
return antiAlias;
}
set {
antiAlias = value;
}
}
}
}
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