项目中用到了Google earth二次开发，现在把搜集的资料进行了一下整理。供大家参考
1、安装google earth，我用的是4.2的版本
2、制作控件，封装google earth API，同时加入windows API,来将google earth的窗口嵌入在 控件中。
代码如下：
Code
using System;using System.Collections.Generic;using System.ComponentModel;using System.Drawing;using System.Data;using System.Linq;using System.Text;using System.Windows.Forms;using System.Runtime.InteropServices;using System.Threading;using EARTHLib;namespace GoogleEarthCOMWrapper
{
public struct RECT
{ public int X1; public int Y1; public int X2; public int Y2;
} public partial class EarthControl : UserControl { private RECT windowRect = new RECT(); IntPtr GEHWnd = IntPtr.Zero; IntPtr GEHrender = IntPtr.Zero; IntPtr GEParentHrender = IntPtr.Zero; int IntGEHrender = 0; private int WM_CLOSE = 0x10; 预定义#region 预定义 public static readonly IntPtr HWND_BOTTOM = new IntPtr(1); public static readonly IntPtr HWND_NOTOPMOST = new IntPtr(-2); public static readonly IntPtr HWND_TOP = new IntPtr(0); public static readonly IntPtr HWND_TOPMOST = new IntPtr(-1); public static readonly UInt32 SWP_NOSIZE = 1; public static readonly UInt32 SWP_NOMOVE = 2; public static readonly UInt32 SWP_NOZORDER = 4; public static readonly UInt32 SWP_NOREDRAW = 8; public static readonly UInt32 SWP_NOACTIVATE = 16; public static readonly UInt32 SWP_FRAMECHANGED = 32; public static readonly UInt32 SWP_SHOWWINDOW = 64; public static readonly UInt32 SWP_HIDEWINDOW = 128; public static readonly UInt32 SWP_NOCOPYBITS = 256; public static readonly UInt32 SWP_NOOWNERZORDER = 512; public static readonly UInt32 SWP_NOSENDCHANGING = 1024; public static readonly int WM_MOUSEWHEEL = 0x020A; public static int GW_CHILD = 5; public static int GW_HWNDNEXT = 2; #endregion public delegate int EnumWindowsProc(IntPtr hwnd, int lParam); API#region API [DllImport("user32", CharSet = CharSet.Auto)] public extern static IntPtr GetParent(IntPtr hWnd); [DllImport("user32", CharSet = CharSet.Auto)] public extern static bool MoveWindow(IntPtr hWnd, int X, int Y, int nWidth, int nHeight, bool bRepaint); [DllImport("user32", CharSet = CharSet.Auto)] public extern static IntPtr SetParent(IntPtr hWndChild, IntPtr hWndNewParent); [DllImport("user32.dll", ExactSpelling = true, CharSet = CharSet.Auto)] public static extern IntPtr GetWindow(IntPtr hWnd, int uCmd); [DllImport("user32.dll")] public static extern bool GetClientRect(IntPtr hWnd, ref RECT lpRect); [DllImport("user32.dll")] public static extern bool GetWindowRect(IntPtr hWnd, ref RECT lpRect); [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)] public static extern bool SetWindowPos(IntPtr hWnd, IntPtr hWndInsertAfter, int x, int y, int cx, int cy, UInt32 uflags); [DllImport("user32.dll", CharSet = CharSet.Auto)] public static extern IntPtr PostMessage(int hWnd, int msg, int wParam, int lParam); #endregion public EarthControl() { InitializeComponent(); } Private Members#region Private Members private ApplicationGEClass _applicationGEClass; #endregion Public Member Functions#region Public Member Functions public void Init() { int i = 0; this._applicationGEClass = new ApplicationGEClass(); while (i < 3 && (GEHWnd == IntPtr.Zero)) { try { GEHWnd = (IntPtr)_applicationGEClass.GetMainHwnd(); i++; } catch { System.Threading.Thread.Sleep(2000); } } while (_applicationGEClass.IsInitialized() == 0) { // Give the app a couple seconds to Load Console.WriteLine("Waiting for Google Earth to initialize"); Thread.Sleep(500); } } public CameraInfoGEClass GetCamera(bool considerTerrain) { try { return _applicationGEClass.GetCamera(considerTerrain ? 1 : 0) as CameraInfoGEClass; } catch (Exception e) { ThrowException(e); } return null; } public void SetCamera(CameraInfoGEClass cameraInfo, double speed) { try { _applicationGEClass.SetCamera(cameraInfo, speed); } catch (Exception e) { ThrowException(e); } } public void SetCameraParams(double lat, double lon, double alt, AltitudeModeGE altMode, double range, double tilt, double azimuth, double speed) { try { _applicationGEClass.SetCameraParams(lat, lon, alt, altMode, range, tilt, azimuth, speed); } catch (Exception e) { ThrowException(e); } } public void SaveScreenShot(string fileName, int quality) { try { _applicationGEClass.SaveScreenShot(fileName, quality); } catch (Exception e) { ThrowException(e); } } public void OpenKmlFile(string fileName, bool suppressMessages) { try { _applicationGEClass.OpenKmlFile(fileName, suppressMessages ? 1 : 0); } catch (Exception e) { ThrowException(e); } } public void OpenKmlFileAndCloseOthers(string fileName, bool suppressMessages) { try { if (_applicationGEClass.GetTemporaryPlaces() != null && _applicationGEClass.GetTemporaryPlaces().Visibility > 0) { _applicationGEClass.GetTemporaryPlaces().Visibility = 0; } _applicationGEClass.OpenKmlFile(fileName, suppressMessages ? 1 : 0); } catch (Exception e) { ThrowException(e); } } public void LoadKmlData(string data) { try { _applicationGEClass.LoadKmlData(ref data); } catch (Exception e) { ThrowException(e); } } public FeatureGEClass GetFeatureByName(string name) { try { return _applicationGEClass.GetFeatureByName(name) as FeatureGEClass; } catch (Exception e) { ThrowException(e); } return null; } public FeatureGEClass GetFeatureByHref(string href) { try { return _applicationGEClass.GetFeatureByHref(href) as FeatureGEClass; } catch (Exception e) { ThrowException(e); } return null; } public void SetFeatureView(FeatureGEClass feature, double speed) { try { _applicationGEClass.SetFeatureView(feature, speed); } catch (Exception e) { ThrowException(e); } } public GeoPoint GetPointOnTerrainFromScreenCoords(double screen_x, double screen_y) { try { PointOnTerrainGE ret = _applicationGEClass.GetPointOnTerrainFromScreenCoords(screen_x, screen_y); //GeoPoint gp = new GeoPoint((double)ret.GetValue(0), (double)ret.GetValue(1), (double)ret.GetValue(2)); GeoPoint gp = new GeoPoint((double)ret.Latitude, (double)ret.Longitude, (double)ret.Altitude); return gp; } catch(Exception e) { ThrowException(e); } return new GeoPoint(0, 0, 0); } public bool IsInitialized() { try { return (_applicationGEClass.IsInitialized() == 0) ? false : true; } catch (Exception e) { ThrowException(e); } return false; } public bool IsOnline() { try { return (_applicationGEClass.IsOnline() == 0) ? false : true; } catch (Exception e) { ThrowException(e); } return false; } public void Login() { try { _applicationGEClass.Login(); } catch (Exception e) { ThrowException(e); } } public void Logout() { try { _applicationGEClass.Logout(); } catch (Exception e) { ThrowException(e); } } public void ShowDescriptionBalloon(FeatureGEClass feature) { try { _applicationGEClass.ShowDescriptionBalloon(feature); } catch (Exception e) { ThrowException(e); } } public void HideDescriptionBalloons() { try { _applicationGEClass.HideDescriptionBalloons(); } catch (Exception e) { ThrowException(e); } } public FeatureGEClass GetHighlightedFeature() { try { return _applicationGEClass.GetHighlightedFeature() as FeatureGEClass; } catch (Exception e) { ThrowException(e); } return null; } public FeatureGEClass GetMyPlaces() { try { return _applicationGEClass.GetMyPlaces() as FeatureGEClass; } catch (Exception e) { ThrowException(e); } return null; } public FeatureGEClass GetTemporaryPlaces() { try { return _applicationGEClass.GetTemporaryPlaces() as FeatureGEClass; } catch (Exception e) { ThrowException(e); } return null; } public FeatureCollectionGEClass GetLayersDatabases() { try { return _applicationGEClass.GetLayersDatabases() as FeatureCollectionGEClass; } catch (Exception e) { ThrowException(e); } return null; } public int GetMainHwnd() { try { return _applicationGEClass.GetMainHwnd(); } catch (Exception e) { ThrowException(e); } return 0; } #endregion Windows Control#region Windows Control public void TakeIn() { //GoogleEarthCOMWrapper.NativeMethods.SetParent(GEHrender, this.tabControl1.TabPages[0].Handle); //GoogleEarthCOMWrapper.NativeMethods.MoveWindow(GEHrender, 0, 0, this.tabControl1.TabPages[0].Width, this.tabControl1.TabPages[0].Height, true); //GoogleEarthCOMWrapper.NativeMethods.GetClientRect(GEParentHrender, ref windowRect); //GoogleEarthCOMWrapper.NativeMethods.SetWindowPos(GEHWnd, GoogleEarthCOMWrapper.NativeMethods.HWND_BOTTOM, 0, 0, 0, 0, //GoogleEarthCOMWrapper.NativeMethods.SWP_NOSIZE + GoogleEarthCOMWrapper.NativeMethods.SWP_HIDEWINDOW); if (_applicationGEClass != null) { IntGEHrender = _applicationGEClass.GetRenderHwnd(); GEHWnd = (IntPtr)_applicationGEClass.GetMainHwnd(); GEHrender = (IntPtr)IntGEHrender; GEParentHrender = (IntPtr)GetParent(GEHrender); SetParent(GEHrender, this.Handle); MoveWindow(GEHrender, 0, 0, this.Width, this.Height, true); GetClientRect(GEParentHrender, ref windowRect); SetWindowPos(GEHWnd,HWND_BOTTOM, 0, 0, 0, 0,SWP_NOSIZE +SWP_HIDEWINDOW); } } #endregion Public Properties#region Public Properties public int StreamingProgressPercentage { get { return _applicationGEClass.StreamingProgressPercentage; } } public double AutoPilotSpeed { get { return _applicationGEClass.AutoPilotSpeed; } set { _applicationGEClass.AutoPilotSpeed = value; } } public ViewExtentsGEClass ViewExtents { get { return _applicationGEClass.ViewExtents as ViewExtentsGEClass; } } public int VersionMajor { get { return _applicationGEClass.VersionMajor; } } public int VersionMinor { get { return _applicationGEClass.VersionMinor; } } public int VersionBuild { get { return _applicationGEClass.VersionBuild; } } public AppTypeGE VersionAppType { get { return _applicationGEClass.VersionAppType; } } public double ElevationExaggeration { get { return _applicationGEClass.ElevationExaggeration; } set { _applicationGEClass.ElevationExaggeration = value; } } #endregion Private Helpers#region Private Helpers private void ThrowException(Exception e) { string message = "Unknown Exception"; Exception ret = new Exception(message); if (e is System.Runtime.InteropServices.COMException) { uint errorCode = (uint)((System.Runtime.InteropServices.COMException)e).ErrorCode; //switch (errorCode) //{ // case 0x80048002: // message = "GoogleEarth not initilaized"; // ret = new ApplicationUninitializedException(message, e); // break; // case 0x80048004: // message = "Feature has no view"; // ret = new FeatureHasNoViewException(message, e); // break; // case 0x80048001: // message = "Invalid or deleted feature"; // ret = new InvalidOrDeletedFeatureException(message, e); // break; //} } throw ret; } #endregion public void SendMouseWheel(MouseEventArgs e) { if (IntGEHrender != 0) { PostMessage(IntGEHrender, WM_MOUSEWHEEL, e.Delta, e.Delta); } } protected override void DestroyHandle() { if (GEHWnd != IntPtr.Zero) { // Post a colse message PostMessage(GEHWnd.ToInt32(), WM_CLOSE, 0, 0); // Delay for it to get the message System.Threading.Thread.Sleep(1000); // Clear internal handle GEHWnd = IntPtr.Zero; GEHrender = IntPtr.Zero; } base.DestroyHandle(); } protected override void OnResize(EventArgs e) { base.OnResize(e); if (GEHrender != IntPtr.Zero) { MoveWindow(GEHrender, 0, 0, this.Width, this.Height, true); } } }
}
4、使用控件
Code
using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Windows.Forms;namespace Test{ public partial class Form1 : Form { public Form1() { InitializeComponent(); } //启动google earth private void button1_Click(object sender, EventArgs e) { earthControl1.Init(); } //将google earth嵌入到控件中 private void button2_Click(object sender, EventArgs e) { earthControl1.TakeIn(); } //传递滚轮事件到google earth 中 protected override void OnMouseWheel(MouseEventArgs e) { base.OnMouseWheel(e); if (earthControl1.Bounds.Contains(e.X, e.Y)) { earthControl1.SendMouseWheel(e); } } }}
这个控件还是个雏形，还有很多方面没有考虑，比如说google earth的销毁等。