winfrom利用WebBrowser将网页整页导出成图片

按钮事件

private void btn_exp_Click(object sender, EventArgs e)
{
	string url = this.txt_url.Text.Trim();
	Bitmap MyImage = WdWebSite.setImage.GetHtmlImage(new Uri(url));
	MyImage.Save(@"d:/1.png");
	Image img = MyImage as Image;
	pictureBox1.Image = img;
	MessageBox.Show("ok");
}

建立一个setImage类

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Drawing.Imaging;
using System.Runtime.InteropServices;
using System.Security;

namespace WdWebSite
{
	public class setImage
	{
		public static Bitmap GetHtmlImage(Uri UrlString)
		{
			WebBrowser MyControl = new WebBrowser();
			MyControl.Size = new Size(10, 10);
			MyControl.Url = UrlString;
			while (MyControl.ReadyState != WebBrowserReadyState.Complete)
			{
				Application.DoEvents();
			}
		
			MyControl.Width = MyControl.Document.Body.ScrollRectangle.Width;
			MyControl.Height= MyControl.Document.Body.ScrollRectangle.Height;
			MyControl.Url = UrlString;
			WebControlImage.Snapshot snap = new WebControlImage.Snapshot();
			Bitmap MyImage= snap.TakeSnapshot(MyControl.ActiveXInstance, new Rectangle(0, 0, MyControl.Width, MyControl.Height));
			MyControl.Dispose();
			return MyImage;
		} 
		
		/// 

		/// WebBrowser获取图形
		/// 
		private 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)
					{
						this.left = r.X;
						this.top = r.Y;
						this.right = r.Right;
						this.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 NativeMethods.COMRECT FromXYWH(int x, int y, int width, int height)
					{
						return new NativeMethods.COMRECT(x, y, x + width, y + height);
					}
					public override string ToString()
					{
						return string.Concat(new object[] { "Left = ", this.left, " Top ", this.top, " Right = ", this.right, " Bottom = ", this.bottom });
					}
				}
				[StructLayout(LayoutKind.Sequential)]
				public sealed class tagLOGPALETTE
				{
					[MarshalAs(UnmanagedType.U2)]
					public short palVersion;
					[MarshalAs(UnmanagedType.U2)]
					public short palNumEntries;
				}
			}
			public class Snapshot
			{
				/// 

				/// 取快照
				/// 
				/// Com 对象
				/// 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
					UnsafeNativeMethods.IViewObject ViewObject = null;
					IntPtr pViewObject = IntPtr.Zero;
					//内存图
					Bitmap pPicture = new Bitmap(bmpRect.Width, bmpRect.Height);
					Graphics hDrawDC = Graphics.FromImage(pPicture);
					//获取接口
					object hret = Marshal.QueryInterface(Marshal.GetIUnknownForObject(pUnknown),
					ref UnsafeNativeMethods.IID_IViewObject, out pViewObject);
					try
					{
						ViewObject = Marshal.GetTypedObjectForIUnknown(pViewObject, typeof(UnsafeNativeMethods.IViewObject)) as UnsafeNativeMethods.IViewObject;
						//调用Draw方法
						ViewObject.Draw((int)System.Runtime.InteropServices.ComTypes.DVASPECT.DVASPECT_CONTENT,
						-1,
						IntPtr.Zero,
						null,
						IntPtr.Zero,
						hDrawDC.GetHdc(),
						new NativeMethods.COMRECT(bmpRect),
						null,
						IntPtr.Zero,
						0);
					}
					catch (Exception ex)
					{
						Console.WriteLine(ex.Message);
						throw ex;
					}
					//释放
					hDrawDC.Dispose();
					return pPicture;
				}
			}
			[SuppressUnmanagedCodeSecurity]
			internal static class UnsafeNativeMethods
			{
				public static Guid IID_IViewObject = 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)] System.Runtime.InteropServices.ComTypes.IAdviseSink pAdvSink);
					void GetAdvise([In, Out, MarshalAs(UnmanagedType.LPArray)] int[] paspects, [In, Out, MarshalAs(UnmanagedType.LPArray)] int[] advf, [In, Out, MarshalAs(UnmanagedType.LPArray)] System.Runtime.InteropServices.ComTypes.IAdviseSink[] pAdvSink);
				}
			}
		}
	}
}

ps：好像通过ajax访问的导出图片有问题。

引用 https://fanhuaxiaodong.lofter.com/post/1d1bd792_12e8047f3