根据网站地址将网页保存为图片(网页快照)
封装好的辅助类：
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.ComTypes;
using System.Security;
using System.Windows.Forms;
namespace Whir.Software.StaticFiles
{
///
/// 图片类型枚举
///
public enum ImageType
{
GIF = 0,
JPG = 1,
PNG = 2
}
///
/// 图片辅助类
///
public class ImageHelper
{
///
/// 将Url地址保存为图片
///
/// 网页路径
/// 图片存放路径
/// 图片类型
///
public static string SaveUrlToImage(string url, string savePath, ImageType imageType)
{
var uri = new Uri(url);
using (var bit = GetHtmlImage(uri, Screen.PrimaryScreen.Bounds.Width))
{
switch (imageType)
{
case ImageType.GIF:
bit.Save(savePath, ImageFormat.Gif);
break;
case ImageType.JPG:
bit.Save(savePath, ImageFormat.Jpeg);
break;
case ImageType.PNG:
bit.Save(savePath, ImageFormat.Png);
break;
default:
bit.Save(savePath, ImageFormat.Jpeg);
break;
}
return savePath;
}
}
protected static Bitmap GetHtmlImage(Uri urlString, int width)
{
using (var control = new WebBrowser { Size = new Size(width, 10), Url = urlString, ScriptErrorsSuppressed = true })
{
while (control.ReadyState != WebBrowserReadyState.Complete)
{
Application.DoEvents();
}
if (control.Document != null)
{
if (control.Document.Body != null)
{
control.Height = control.Document.Body.ScrollRectangle.Height + 20;
}
}
control.Url = urlString;
var snap = new WebControlImage.Snapshot();
var bitmap = snap.TakeSnapshot(control.ActiveXInstance, new Rectangle(0, 0, control.Width, control.Height));
control.Dispose();
return bitmap;
}
}
/// WebBrowser获取图形
protected class WebControlImage
{
internal static class NativeMethods
{
[StructLayout(LayoutKind.Sequential)]
public sealed class TagDvtargetdevice
{
[MarshalAs(UnmanagedType.U4)]
public int tdSize;
[MarshalAs(UnmanagedType.U2)]
public short tdDriverNameOffset;
[MarshalAs(UnmanagedType.U2)]
public short tdDeviceNameOffset;
[MarshalAs(UnmanagedType.U2)]
public short tdPortNameOffset;
[MarshalAs(UnmanagedType.U2)]
public short tdExtDevmodeOffset;
}
[StructLayout(LayoutKind.Sequential)]
public class Comrect
{
public int left;
public int top;
public int right;
public int bottom;
public Comrect()
{
}
public Comrect(Rectangle r)
{
left = r.X;
top = r.Y;
right = r.Right;
bottom = r.Bottom;
}
public Comrect(int left, int top, int right, int bottom)
{
this.left = left;
this.top = top;
this.right = right;
this.bottom = bottom;
}
public static Comrect FromXywh(int x, int y, int width, int height)
{
return new Comrect(x, y, x + width, y + height);
}
public override string ToString()
{
return string.Concat("Left = ", left, " Top ", top, " Right = ", right, " Bottom = ", bottom);
}
}
[StructLayout(LayoutKind.Sequential)]
public sealed class TagLogpalette
{
[MarshalAs(UnmanagedType.U2)]
public short palVersion;
[MarshalAs(UnmanagedType.U2)]
public short palNumEntries;
}
}
public class Snapshot
{
/// 图象大小
public Bitmap TakeSnapshot(object pUnknown, Rectangle bmpRect)
{
if (pUnknown == null)
return null;
//必须为com对象
if (!Marshal.IsComObject(pUnknown))
return null;
//IViewObject 接口
IntPtr viewObject;
//内存图
var bitmap = new Bitmap(bmpRect.Width, bmpRect.Height);
var image = Graphics.FromImage(bitmap);
//获取接口
object hret = Marshal.QueryInterface(Marshal.GetIUnknownForObject(pUnknown),
ref UnsafeNativeMethods.IidIViewObject, out viewObject);
try
{
var o =
Marshal.GetTypedObjectForIUnknown(viewObject, typeof(UnsafeNativeMethods.IViewObject)) as
UnsafeNativeMethods.IViewObject;
//调用Draw方法
if (o != null)
o.Draw((int)DVASPECT.DVASPECT_CONTENT,
-1,
IntPtr.Zero,
null,
IntPtr.Zero,
image.GetHdc(),
new NativeMethods.Comrect(bmpRect),
null,
IntPtr.Zero,
0);
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
throw;
}
//释放
image.Dispose();
return bitmap;
}
}
[SuppressUnmanagedCodeSecurity]
internal static class UnsafeNativeMethods
{
public static Guid IidIViewObject = new Guid("{0000010d-0000-0000-C000-000000000046}");
[ComImport, Guid("0000010d-0000-0000-C000-000000000046"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IViewObject
{
[PreserveSig]
int Draw([In, MarshalAs(UnmanagedType.U4)] int dwDrawAspect, int lindex, IntPtr pvAspect,
[In] NativeMethods.TagDvtargetdevice ptd, IntPtr hdcTargetDev, IntPtr hdcDraw,
[In] NativeMethods.Comrect lprcBounds, [In] NativeMethods.Comrect lprcWBounds,
IntPtr pfnContinue,
[In] int dwContinue);
[PreserveSig]
int GetColorSet([In, MarshalAs(UnmanagedType.U4)] int dwDrawAspect, int lindex, IntPtr pvAspect,
[In] NativeMethods.TagDvtargetdevice ptd, IntPtr hicTargetDev,
[Out] NativeMethods.TagLogpalette ppColorSet);
[PreserveSig]
int Freeze([In, MarshalAs(UnmanagedType.U4)] int dwDrawAspect, int lindex, IntPtr pvAspect,
[Out] IntPtr pdwFreeze);
[PreserveSig]
int Unfreeze([In, MarshalAs(UnmanagedType.U4)] int dwFreeze);
void SetAdvise([In, MarshalAs(UnmanagedType.U4)] int aspects,
[In, MarshalAs(UnmanagedType.U4)] int advf,
[In, MarshalAs(UnmanagedType.Interface)] IAdviseSink pAdvSink);
void GetAdvise([In, Out, MarshalAs(UnmanagedType.LPArray)] int[] paspects,
[In, Out, MarshalAs(UnmanagedType.LPArray)] int[] advf,
[In, Out, MarshalAs(UnmanagedType.LPArray)] IAdviseSink[] pAdvSink);
}
}
}
}
}
使用方法：
var url = txtUrl.Text.Trim();
if (url == "")
{
MessageBox.Show("请输入网址");
return;
}
var dir = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
var path = Path.Combine(dir, DateTime.Now.Ticks + ".jpg");
ImageHelper.SaveUrlToImage(txtUrl.Text.Trim(), path, ImageType.JPG);
MessageBox.Show("生成成功！");