C#实现在底图上动态生成文字和图片

/// <summary>
/// 在底图上画指定路径的图片
/// </summary>
/// <param name="g">画板实例</param>
/// <param name="path">图片路径</param>
/// <param name="totalWidth">画区总长度</param>
/// <param name="totalHeight">画区总高度</param>
/// <param name="px">起点X坐标</param>
/// <param name="py">起点Y坐标</param>
  private void FontPic(ref Graphics g, string path, int totalWidth, int totalHeight, int px, int py)
  {
   if (File.Exists(path))
   {
    var pImg = Image.FromFile(path);
    //如果图片大于画布区域，则缩小
    if (totalHeight < pImg.Height && totalWidth < pImg.Width)
    {
     Image newPic = GetReducedImage(pImg, totalWidth, totalHeight);
     if (newPic != null)
     {
      DrawPic(ref g, totalWidth, totalHeight, px, py, newPic);
     }
    }
    else if (totalHeight < pImg.Height && totalWidth >= pImg.Width)
    {
     Image newPic = GetReducedImage(pImg, pImg.Width, totalHeight);
     if (newPic != null)
     {
      DrawPic(ref g, totalWidth, totalHeight, px, py, newPic);
     }
    }
    else if (totalHeight >= pImg.Height && totalWidth < pImg.Width)
    {
     Image newPic = GetReducedImage(pImg, totalWidth, pImg.Height);
     if (newPic != null)
     {
      DrawPic(ref g, totalWidth, totalHeight, px, py, newPic);
     }
    }
    else
    {
     DrawPic(ref g, totalWidth, totalHeight, px, py, pImg);
    }
   }
  }
  /// <summary>
  /// 在图上画图片
  /// </summary>
  /// <param name="g">画板实例</param>
  /// <param name="totalWidth">画区总长度</param>
  /// <param name="totalHeight">画区总高度</param>
  /// <param name="px">起点X坐标</param>
  /// <param name="py">起点Y坐标</param>
  /// <param name="pImg">要画的图片实例</param>
  private void DrawPic(ref Graphics g, int totalWidth, int totalHeight, int px, int py, Image pImg)
  {
   px += GetValue(totalWidth, pImg.Width);
   py += GetValue(totalHeight, pImg.Height);
 
   g.DrawImage(new Bitmap(pImg, new Size(GetSize(totalWidth, pImg.Width), GetSize(totalHeight, pImg.Height))),
    new Rectangle(px, py, totalWidth, totalHeight),
    0, 0, totalWidth, totalHeight, GraphicsUnit.Pixel);
  }
  /// <summary> 
  /// 生成缩略图重载方法1，返回缩略图的Image对象 
  /// </summary> 
  /// <param name="width">缩略图的宽度</param> 
  /// <param name="height">缩略图的高度</param> 
  /// <returns>缩略图的Image对象</returns> 
  public Image GetReducedImage(Image resourceImage, int width, int height)
  {
   try
   {
    Image data = null;
    //用指定的大小和格式初始化Bitmap类的新实例 
    using (Bitmap bitmap = new Bitmap(width, height, PixelFormat.Format32bppArgb))
    {
     //从指定的Image对象创建新Graphics对象 
     using (Graphics graphics = Graphics.FromImage(bitmap))
     {
      //清除整个绘图面并以透明背景色填充 
      //graphics.Clear(Color.Transparent);
      //在指定位置并且按指定大小绘制原图片对象 
      graphics.DrawImage(resourceImage, new Rectangle(0, 0, width, height));
     }
     data = new Bitmap(bitmap);
    }
    return data;
   }
   catch (Exception e)
   {
    throw e;
   }
  }
  /// <summary>
  /// 比较两个值，得到给到给定值（判断是否越界）
  /// </summary>
  /// <param name="total">总长度</param>
  /// <param name="width">指定长度</param>
  /// <returns></returns>
  public int GetSize(int total, int width)
  {
   if (total > width)
   {
    return width;
   }
   else
   {
    return total;
   }
  }
  /// <summary>
  /// 更加传入的值计算得到新值（计算点坐标）
  /// </summary>
  /// <param name="total">总长度</param>
  /// <param name="width">指定长度</param>
  /// <returns></returns>
  private int GetValue(int total, int width)
  {
   return (total - width) / 2;
  }
  /// <summary>
  /// 在图片上画出文字
  /// </summary>
  /// <param name="g">图片对象</param>
  /// <param name="pointX">文字x坐标</param>
  /// <param name="pointY">文字y坐标</param>
  /// <param name="word">文字内容</param>
  /// <param name="textWidth">文本宽度</param>
  /// <param name="textHeight">文本高度</param>
  private static void DrawStringWord(Graphics g, int pointX, int pointY, string word, int textWidth, int textHeight, int fontSize = 30)
  {
   Font font = new Font("微软雅黑", fontSize, (FontStyle.Regular));
   RectangleF textArea = new RectangleF(pointX, pointY, textWidth, textHeight);
   Brush brush = new SolidBrush(Color.Black);
   g.DrawString(word, font, brush, textArea);
  }