C# 图片（png,jpg等）转换ico图标 源码

视频讲解地址 https://www.bilibili.com/video/BV1aU4y1S7rb

核心代码

/// <summary>
/// 图片转换为ico文件
/// </summary>
/// <param name="origin">原图片路径</param>
/// <param name="destination">输出ico文件路径</param>
/// <param name="iconSize">输出ico图标尺寸，不可大于255x255</param>
/// <returns>是否转换成功</returns>
public bool ConvertImageToIcon(string origin, string destination, Size iconSize)
{
    if (iconSize.Width > 255 || iconSize.Height > 255)
    {
        return false;
    }
    Image image = new Bitmap(new Bitmap(origin), iconSize); //先读取已有的图片为bitmap，并缩放至设定大小
    MemoryStream bitMapStream = new MemoryStream(); //存原图的内存流
    MemoryStream iconStream = new MemoryStream(); //存图标的内存流
    image.Save(bitMapStream, ImageFormat.Png); //将原图读取为png格式并存入原图内存流
    BinaryWriter iconWriter = new BinaryWriter(iconStream); //新建二进制写入器以写入目标图标内存流
                                                            /**
                                                             * 下面是根据原图信息，进行文件头写入
                                                             */
    iconWriter.Write((short)0);
    iconWriter.Write((short)1);
    iconWriter.Write((short)1);
    iconWriter.Write((byte)image.Width);
    iconWriter.Write((byte)image.Height);
    iconWriter.Write((short)0);
    iconWriter.Write((short)0);
    iconWriter.Write((short)32);
    iconWriter.Write((int)bitMapStream.Length);
    iconWriter.Write(22);
    //写入图像体至目标图标内存流
    iconWriter.Write(bitMapStream.ToArray());
    //保存流，并将流指针定位至头部以Icon对象进行读取输出为文件
    iconWriter.Flush();
    iconWriter.Seek(0, SeekOrigin.Begin);
    Stream iconFileStream = new FileStream(destination, FileMode.Create);
    Icon icon = new Icon(iconStream);
    icon.Save(iconFileStream); //储存图像
                               /**
                                * 下面开始释放资源
                                */
    iconFileStream.Close();
    iconWriter.Close();
    iconStream.Close();
    bitMapStream.Close();
    icon.Dispose();
    image.Dispose();
    return File.Exists(destination);
}

方法调用如下

 bool b = ConvertImageToIcon(@"d:\1.png", @"d:\1.ico", new Size(64, 64));