[DllImport("kernel32.dll", SetLastError = true)]
 public static extern int WriteProfileString(string lpszSection, string lpszKeyName, string lpszString);

 [DllImport("gdi32")]
 public static extern int AddFontResource(string lpFileName);

 /// <summary>
 /// 安装字体
 /// </summary>
 /// <param name="fontFilePath">字体文件全路径</param>
 /// <returns>是否成功安装字体</returns>
 /// <exception cref="UnauthorizedAccessException">不是管理员运行程序</exception>
 /// <exception cref="Exception">字体安装失败</exception>
 public static bool InstallFont(string fontFilePath)
 {
   try
   {
     System.Security.Principal.WindowsIdentity identity = System.Security.Principal.WindowsIdentity.GetCurrent();

     System.Security.Principal.WindowsPrincipal principal = new System.Security.Principal.WindowsPrincipal(identity);
     //判断当前登录用户是否为管理员
     if (principal.IsInRole(System.Security.Principal.WindowsBuiltInRole.Administrator) == false)
     {
       throw new UnauthorizedAccessException("当前用户无管理员权限，无法安装字体。");
     }
     //获取Windows字体文件夹路径
     string fontPath=Path.Combine(System.Environment.GetEnvironmentVariable("WINDIR") , "fonts",Path.GetFileName(fontFilePath));
     //检测系统是否已安装该字体
     if (!File.Exists(fontPath))
     {
       // File.Copy(System.Windows.Forms.Application.StartupPath + "\\font\\" + FontFileName, FontPath); //font是程序目录下放字体的文件夹
       //将某路径下的字体拷贝到系统字体文件夹下
       File.Copy(fontFilePath, fontPath); //font是程序目录下放字体的文件夹
       AddFontResource(fontPath);

       //Res = SendMessage(HWND_BROADCAST, WM_FONTCHANGE, 0, 0); 
       //WIN7下编译会出错，不清楚什么问题。注释就行了。 
       //安装字体
       WriteProfileString("fonts", Path.GetFileNameWithoutExtension(fontFilePath) + "(TrueType)", Path.GetFileName(fontFilePath));
     }
   }
   catch (Exception ex)
   {
     throw new Exception(string.Format($"[{Path.GetFileNameWithoutExtension(fontFilePath)}] 字体安装失败！原因：{ex.Message}" ));
   }
   return true;
 }

/// <summary>
/// 如何使用资源文件中的字体，无安装无释放
/// </summary>
/// <param name="bytes">资源文件中的字体文件</param>
/// <returns></returns>
public Font GetResoruceFont(byte[] bytes)
{
  System.Drawing.Text.PrivateFontCollection pfc = new System.Drawing.Text.PrivateFontCollection();
  IntPtr MeAdd = Marshal.AllocHGlobal(bytes.Length);
  Marshal.Copy(bytes, 0, MeAdd, bytes.Length);
  pfc.AddMemoryFont(MeAdd, bytes.Length);
  return new Font(pfc.Families[0], 15, FontStyle.Regular);
}

/// <summary>
/// 通过文件获取字体
/// </summary>
/// <param name="filePath">文件全路径</param>
/// <returns>字体</returns>
public Font GetFontByFile(string filePath)
{
  //程序直接调用字体文件，不用安装到系统字库中。
  System.Drawing.Text.PrivateFontCollection pfc = new System.Drawing.Text.PrivateFontCollection();
  pfc.AddFontFile(filePath);//字体文件的路径
  Font font = new Font(pfc.Families[0], 24, FontStyle.Regular, GraphicsUnit.Point, 0);//font就是通过文件创建的字体对象
  return font;
}

[System.Runtime.InteropServices.DllImport("coredll", EntryPoint = "AddFontResource")]
 private static extern int AddFontResource([In,MarshalAs(UnmanagedType.LPWStr)]string fontSource);

 [DllImport("coredll", EntryPoint = "SendMessage")]
 private static extern int SendMessage(IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);
 private void Fun()
 {
   int installFont = AddFontResource(@"/SDMEM/MSYH.TTF"); //这是字体的安装 返回不为0即成功
   SendMessage((IntPtr)0xffff, 0x001d, IntPtr.Zero, IntPtr.Zero); //通知其它正在运行的应用程序，有新字体注册了           
   InstalledFontCollection enumFonts = new InstalledFontCollection();
   FontFamily[] fonts = enumFonts.Families;
   foreach (FontFamily font in fonts)
   {
     MessageBox.Show(font.Name);
   }
 }

/// <summary>
/// 检查字体是否存在
/// </summary>
/// <param name="familyName">字体名称</param>
/// <returns></returns>
public static bool CheckFont(string familyName)
{
  string FontPath = Path.Combine(System.Environment.GetEnvironmentVariable("WINDIR"), "fonts", Path.GetFileName(familyName));
  //检测系统是否已安装该字体
  return File.Exists(FontPath);
}

/// <summary>
/// 检测某种字体样式是否可用
/// </summary>
/// <param name="familyName">字体名称</param>
/// <param name="fontStyle">字体样式</param>
/// <returns></returns>
public bool CheckFont(string familyName, FontStyle fontStyle= FontStyle.Regular )
{
  InstalledFontCollection installedFontCollection = new InstalledFontCollection();
  FontFamily[] fontFamilies = installedFontCollection.Families;
  foreach(var item in fontFamilies)
  {
    if (item.Name.Equals(familyName))
    {
      return item.IsStyleAvailable(fontStyle);
    }
  }
  return false;
}