生成验证码
/// <summary>
/// 生成二维码
/// </summary>
/// <param name="webRootPath">wwwroot目录</param>
/// <param name="verifyCode">验证码</param>
/// <param name="width">图片宽度</param>
/// <param name="height">图片高度</param>
/// <returns></returns>
public static byte[] CreateByteByImgVerifyCode(string webRootPath, string verifyCode, int width = 120, int height = 50)
{
using Image image = new Image<Rgba32>(width, height);
//漆底色白色
image.Mutate(x => x.DrawLine(Pens.DashDot(Color.White, width), new PointF[] { new PointF() { X = 0, Y = 0 }, new PointF() { X = width, Y = height } }));
FontCollection collection = new();
FontFamily family = collection.Add(Path.Combine(webRootPath, "fonts", "FZHTJW.TTF"));
Font font = family.CreateFont(20, FontStyle.Bold);
PointF startPointF = new PointF(5, 5);
Random random = new Random(); //随机数产生器
Color[] colors = new Color[] { Color.Red, Color.Blue, Color.Green, Color.Purple, Color.Peru, Color.LightSeaGreen, Color.Lime, Color.Magenta, Color.Maroon, Color.MediumBlue, Color.MidnightBlue, Color.Navy };
//绘制大小
for (int i = 0; i < verifyCode.Length; i++)
{
image.Mutate(x => x.DrawText(verifyCode[i].ToString(), font, colors[random.Next(colors.Length)], startPointF));
startPointF.X += (int)(width - 10) / verifyCode.Length;
startPointF.Y = random.Next(5, 10);
}
var pen = Pens.DashDot(Color.Silver, 1);
//绘制干扰线
for (var k = 0; k < 30; k++)
{
PointF[] points = new PointF[2];
points[0] = new PointF(random.Next(width), random.Next(height));
points[1] = new PointF(random.Next(width), random.Next(height));
image.Mutate(x => x.DrawLine(pen, points));
}
using MemoryStream stream = new MemoryStream();
image.Save(stream, PngFormat.Instance);
//输出图片流
return stream.ToArray();
}
压缩图片
/// <summary>
/// 生成缩略图并保存
/// </summary>
/// <param name="sFile">原图路径</param>
/// <param name="dFile">生成的缩略图路径</param>
/// <param name="dHeight">缩略图高度</param>
/// <param name="dWidth">缩略图宽度</param>
/// <param name="flag">压缩质量1-100</param>
/// <returns></returns>
public static bool GetPicThumbnail(string sFile, string dFile, int dHeight, int dWidth, int flag)
{
Image sourceImage = null;
FileStream compressImageFile = null;
try
{
sourceImage = Image.Load(sFile);
if (sourceImage == null)
{
return false;
}
var originWidth = sourceImage.Width;
var originHeight = sourceImage.Height;
if (dWidth <= 0 && dHeight <= 0)
{
//如果都是0就是原图
dWidth = originWidth;
dHeight = originHeight;
}
int sW;
int sH;
//按比例缩放
if (originWidth > dWidth || originHeight > dHeight)
{
if ((originWidth * dHeight) > (originHeight * dWidth))
{
sW = dWidth;
sH = (dWidth * originHeight) / originWidth;
}
else
{
sH = dHeight;
sW = (originWidth * dHeight) / originHeight;
}
}
else
{
sW = originWidth;
sH = originHeight;
}
缩放并且换转为灰度图
//image.Mutate(x => x
// .Resize(image.Width / 2, image.Height / 2) // 缩放
// .Grayscale()); // 转灰度图
sourceImage.Mutate(x => x.Resize(sW, sH));
//获取编码器
var iamgeFormat = sourceImage.Metadata.DecodedImageFormat;
IImageEncoder encoder = null;
switch (iamgeFormat.Name.ToLower())
{
case "png":
case "gif":
case "bmp":
break;
default:
encoder = new JpegEncoder()
{
Quality = flag //Use variable to set between 5-30 based on your requirements
};
break;
}
compressImageFile = new FileStream(dFile, FileMode.CreateNew, FileAccess.Write);
if(encoder!=null)
{
sourceImage.Save(compressImageFile, encoder);
}
else
{
sourceImage.Save(compressImageFile, iamgeFormat);
}
return true;
}
catch
{
return false;
}
finally
{
compressImageFile?.Dispose();
sourceImage?.Dispose();
}
}
/// <summary>
/// 生成缩略图并返回byte数组
/// </summary>
/// <param name="sFile">原图路径</param>
/// <param name="dHeight">缩略图高度</param>
/// <param name="dWidth">缩略图宽度</param>
/// <param name="flag">压缩质量1-100</param>
/// <returns></returns>
public static byte[]? GetPicThumbnail(string sFile, int dHeight, int dWidth, int flag)
{
Image sourceImage = null;
MemoryStream compressImageFile = null;
try
{
sourceImage = Image.Load(sFile);
if (sourceImage == null)
{
return null;
}
var originWidth = sourceImage.Width;
var originHeight = sourceImage.Height;
if (dWidth <= 0 && dHeight <= 0)
{
//如果都是0就是原图
dWidth = originWidth;
dHeight = originHeight;
}
int sW;
int sH;
//按比例缩放
if (originWidth > dWidth || originHeight > dHeight)
{
if ((originWidth * dHeight) > (originHeight * dWidth))
{
sW = dWidth;
sH = (dWidth * originHeight) / originWidth;
}
else
{
sH = dHeight;
sW = (originWidth * dHeight) / originHeight;
}
}
else
{
sW = originWidth;
sH = originHeight;
}
sourceImage.Mutate(x => x.Resize(sW, sH));
//获取编码器
//获取编码器
var iamgeFormat = sourceImage.Metadata.DecodedImageFormat;
IImageEncoder encoder = null;
switch (iamgeFormat.Name.ToLower())
{
case "png":
case "gif":
case "bmp":
break;
default:
encoder = new JpegEncoder()
{
Quality = flag //Use variable to set between 5-30 based on your requirements
};
break;
}
compressImageFile = new MemoryStream();
if (encoder != null)
{
sourceImage.Save(compressImageFile, encoder);
}
else
{
sourceImage.Save(compressImageFile, iamgeFormat);
}
return compressImageFile.ToArray();
}
catch
{
return null;
}
finally
{
compressImageFile?.Dispose();
sourceImage?.Dispose();
}
}
生成海报
https://blog.csdn.net/qq_36437991/article/details/133383006
生成二维码
还需要依赖于QRCode库
有一个和image-sharp深度继承的库，它是跨平台的，不过目前最新版的qrcode应该也是跨平台的
/// <summary>
/// 将二维码转化为base64格式
/// </summary>
/// <param name="content">二维码内容</param>
/// <param name="iconPath">logo图片地址</param>
/// <returns></returns>
public string ToBase64QRCode(string content, string iconPath)
{
QRCodeGenerator qrGenerator = new QRCodeGenerator();
QRCodeData qrCodeData = qrGenerator.CreateQrCode(content, QRCodeGenerator.ECCLevel.H);
var qrCode = new BitmapByteQRCode(qrCodeData);
var qrCodeImage = qrCode.GetGraphic(5);
if (string.IsNullOrEmpty(iconPath))
{
var res = Convert.ToBase64String(qrCodeImage);
return res;
}
var iconImg = Image.Load(iconPath);
iconImg.Mutate(x => x.Resize(60, 60, KnownResamplers.Box));
var qrcodeImg = Image.Load(qrCodeImage);
var left = qrcodeImg.Width / 2 - iconImg.Width / 2;
var top = qrcodeImg.Height / 2 - iconImg.Height / 2;
qrcodeImg.Mutate(t => t.DrawImage(iconImg, new Point(left, top), 1f));
var qrcodeStream = new MemoryStream();
qrcodeImg.Save(qrcodeStream, new PngEncoder());
return Convert.ToBase64String(qrcodeStream.ToArray());
}
