????读完这篇文章里你能收获到
- .Net跨平台在Linux中及Windows中都可生成验证码
- 两套已验证过的实现方案代码封装，即Copy即用
- 快速在Centos 7.x中安装Linux字体
文章目录
一、安装Linux字体
我以Centos 7.x为例，其他系统自行百度：xx系统安装字体
1. 查看字体库
如果没数据的话就继续往下走，先把字体库安装好
如果有数据的话，则跳过，直接进入第二点使用代码
fc-list
2. 运行安装字体库
yum -y install fontconfig
3. 安装ttmkfdir
用来搜索目录中所有的字体信息，并汇总生成fonts.scale文件
yum -y install ttmkfdir
4. 查看字体库是否已安装成功
fc-list
二、.NET 代码实现封装
1. SixLabors.ImageSharp方案
1.1 效果
1.2 源码链接
1.3 Nuget依赖
<!--Nuget依赖-->
<PackageReference Include="SixLabors.ImageSharp" Version="2.1.3" />
<PackageReference Include="SixLabors.ImageSharp.Drawing" Version="1.0.0-beta15" />
1.4 Helper代码封装
using SixLabors.ImageSharp;
using SixLabors.Fonts;
using SixLabors.ImageSharp.PixelFormats;
using SixLabors.ImageSharp.Processing;
using SixLabors.ImageSharp.Drawing.Processing;
using System;
using System.Linq;
namespace VertifyCode
{
public class VerifyCodeHelper
{
private static readonly Color[] Colors = { Color.Black, Color.Red, Color.Blue, Color.Green, Color.Orange, Color.Brown,
Color.Brown,Color.DarkBlue};
private static readonly char[] Chars = { '2','3','4','5','6','8','9',
'A','B','C','D','E','F','G','H','J','K', 'L','M','N','P','R','S','T','W','X','Y' };
//private static readonly int Width = 90;
//private static readonly int Height = 35;
private static string GenCode(int num)
{
var code = string.Empty;
var r = new Random();
for (int i = 0; i < num; i++)
{
code += Chars[r.Next(Chars.Length)].ToString();
}
return code;
}
public static (string code, byte[] bytes) CreateValidateGraphic(int CodeLength, int Width = 80, int Height = 40, int FontSize = 14)
{
var code = GenCode(CodeLength);
var r = new Random();
using var image = new Image<Rgba32>(Width, Height);
// 字体
var font = SystemFonts.CreateFont(SystemFonts.Families.First().Name, FontSize, FontStyle.Bold);
image.Mutate(ctx =>
{
// 白底背景
ctx.Fill(Color.White);
// 画验证码
for (int i = 0; i < code.Length; i++)
{
ctx.DrawText(code[i].ToString()
, font
, Colors[r.Next(Colors.Length)]
, new PointF(20 * i + 10, r.Next(2, 12)));
}
// 画干扰线
for (int i = 0; i < 6; i++)
{
var pen = new Pen(Colors[r.Next(Colors.Length)], 1);
var p1 = new PointF(r.Next(Width), r.Next(Height));
var p2 = new PointF(r.Next(Width), r.Next(Height));
ctx.DrawLines(pen, p1, p2);
}
// 画噪点
for (int i = 0; i < 60; i++)
{
var pen = new Pen(Colors[r.Next(Colors.Length)], 1);
var p1 = new PointF(r.Next(Width), r.Next(Height));
var p2 = new PointF(p1.X + 1f, p1.Y + 1f);
ctx.DrawLines(pen, p1, p2);
}
});
using var ms = new System.IO.MemoryStream();
// 格式 自定义
image.SaveAsPng(ms);
return (code, ms.ToArray());
}
}
}
2. SkiaSharp方案
2.1 效果
2.2 源码链接
2.3 Nuget依赖
<!--Nuget依赖-->
<PackageReference Include="SkiaSharp" Version="2.88.3" />
<PackageReference Include="SkiaSharp.NativeAssets.Linux.NoDependencies" Version="2.88.3" />
2.4 Helper代码封装
using SkiaSharp;
using System;
namespace VertifyCode
{
public class VerifyCodeImageSharpHelper
{
private static readonly char[] Chars = { '2','3','4','5','6','8','9',
'A','B','C','D','E','F','G','H','J','K', 'L','M','N','P','R','S','T','W','X','Y' };
private static string GenCode(int num)
{
var code = string.Empty;
var r = new Random();
for (int i = 0; i < num; i++)
{
code += Chars[r.Next(Chars.Length)].ToString();
}
return code;
}
public static (string code, byte[] bytes) CreateValidateGraphic(int codeLength, int width = 80, int height = 40, int fontSize = 20)
{
var code = GenCode(codeLength);
byte[] imageBytes = null;
int image2d_x = 0;
int image2d_y = 0;
SKRect size;
int compensateDeepCharacters = 0;
using (SKPaint drawStyle = CreatePaint(fontSize))
{
size = MeasureText(code, drawStyle);
image2d_x = width;
image2d_y = height;
}
using (SKBitmap image2d = new SKBitmap(image2d_x, image2d_y, SKColorType.Bgra8888, SKAlphaType.Premul))
{
using (SKCanvas canvas = new SKCanvas(image2d))
{
canvas.DrawColor(SKColors.Black); // Clear
using (SKPaint drawStyle = CreatePaint(fontSize))
{
canvas.DrawText(code, 0 + 5, image2d_y - 5 - compensateDeepCharacters, drawStyle);
}
using (SKImage img = SKImage.FromBitmap(image2d))
{
using (SKData p = img.Encode(SKEncodedImageFormat.Png, 100))
{
imageBytes = p.ToArray();
}
}
}
return (code,imageBytes);
}
}
private static SKPaint CreatePaint(int fontSize)
{
string font = @"";
font = @"Arial";
font = @"Liberation Serif";
font = @"Segoe Script";
font = @"Consolas";
font = @"Comic Sans MS";
font = @"SimSun";
font = @"Impact";
return CreatePaint(SKColors.White, font, fontSize, SKTypefaceStyle.Normal);
}
private static SKPaint CreatePaint(SKColor color, string fontName, float fontSize, SKTypefaceStyle fontStyle)
{
SKTypeface font = SKTypeface.FromFamilyName(fontName, fontStyle);
SKPaint paint = new SKPaint();
paint.IsAntialias = true;
paint.Color = color;
// paint.StrokeCap = SKStrokeCap.Round;
paint.Typeface = font;
paint.TextSize = fontSize;
return paint;
}
// MeasureText("Impact", 12, SKTypefaceStyle.Bold);
internal static SKRect MeasureText(string text, SKPaint paint)
{
SKRect rect = new SKRect();
paint.MeasureText(text, ref rect);
return rect;
} // End Function MeasureText
}
}