借鑑博客：
1..net core ZKWeb.System.Drawing 生成圖片驗證碼
2.Asp.NET Core+ABP框架+IdentityServer4+MySQL+Ext JS之驗證碼
功能主要使用類VerifyCodeHelper借鑑第一個博客，其餘爲自己設計，如果有更好的方案歡迎留言交流，謝謝。
1.在應用層添加包ZKWeb.System.Drawing。
通常使用System.Drawing.Common。這是一個執行圖形相關任務的流行的API，在這裏我們使用ZKWeb.System.Drawing代替他
2.在創建二維碼的使用類
using System;
using System.DrawingCore;
using System.DrawingCore.Drawing2D;
using System.DrawingCore.Imaging;
using System.IO;
namespace XXXX.Common.Core.Helper
{
public sealed class VerifyCodeHelper
{
#region 單例模式
//創建私有化靜態obj鎖
private static readonly object _ObjLock = new object();
//創建私有靜態字段，接收類的實例化對象
private static VerifyCodeHelper _VerifyCodeHelper = null;
//構造函數私有化
private VerifyCodeHelper() { }
//創建單利對象資源並返回
public static VerifyCodeHelper GetSingleObj()
{
if (_VerifyCodeHelper == null)
{
lock (_ObjLock)
{
if (_VerifyCodeHelper == null)
_VerifyCodeHelper = new VerifyCodeHelper();
}
}
return _VerifyCodeHelper;
}
#endregion
#region 生產驗證碼
public enum VerifyCodeType { NumberVerifyCode, AbcVerifyCode, MixVerifyCode };
/// <summary>
/// 1.數字驗證碼
/// </summary>
/// <param name="length"></param>
/// <returns></returns>
private string CreateNumberVerifyCode(int length)
{
int[] randMembers = new int[length];
int[] validateNums = new int[length];
string validateNumberStr = "";
//生成起始序列值
int seekSeek = unchecked((int)DateTime.Now.Ticks);
Random seekRand = new Random(seekSeek);
int beginSeek = seekRand.Next(0, Int32.MaxValue - length * 10000);
int[] seeks = new int[length];
for (int i = 0; i < length; i++)
{
beginSeek += 10000;
seeks[i] = beginSeek;
}
//生成隨機數字
for (int i = 0; i < length; i++)
{
Random rand = new Random(seeks[i]);
int pownum = 1 * (int)Math.Pow(10, length);
randMembers[i] = rand.Next(pownum, Int32.MaxValue);
}
//抽取隨機數字
for (int i = 0; i < length; i++)
{
string numStr = randMembers[i].ToString();
int numLength = numStr.Length;
Random rand = new Random();
int numPosition = rand.Next(0, numLength - 1);
validateNums[i] = Int32.Parse(numStr.Substring(numPosition, 1));
}
//生成驗證碼
for (int i = 0; i < length; i++)
{
validateNumberStr += validateNums[i].ToString();
}
return validateNumberStr;
}
/// <summary>
/// 2.字母驗證碼
/// </summary>
/// <param name="length">字符長度</param>
/// <returns>驗證碼字符</returns>
private string CreateAbcVerifyCode(int length)
{
char[] verification = new char[length];
char[] dictionary = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'
};
Random random = new Random();
for (int i = 0; i < length; i++)
{
verification[i] = dictionary[random.Next(dictionary.Length - 1)];
}
return new string(verification);
}
/// <summary>
/// 3.混合驗證碼
/// </summary>
/// <param name="length">字符長度</param>
/// <returns>驗證碼字符</returns>
private string CreateMixVerifyCode(int length)
{
char[] verification = new char[length];
char[] dictionary = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'
};
Random random = new Random();
for (int i = 0; i < length; i++)
{
verification[i] = dictionary[random.Next(dictionary.Length - 1)];
}
return new string(verification);
}
/// <summary>
/// 產生驗證碼（隨機產生4-6位）
/// </summary>
/// <param name="type">驗證碼類型：數字，字符，符合</param>
/// <returns></returns>
public string CreateVerifyCode(VerifyCodeType type)
{
string verifyCode = string.Empty;
Random random = new Random();
int length = 4;// random.Next(4, 6);
switch (type)
{
case VerifyCodeType.NumberVerifyCode:
verifyCode = GetSingleObj().CreateNumberVerifyCode(length);
break;
case VerifyCodeType.AbcVerifyCode:
verifyCode = GetSingleObj().CreateAbcVerifyCode(length);
break;
case VerifyCodeType.MixVerifyCode:
verifyCode = GetSingleObj().CreateMixVerifyCode(length);
break;
}
return verifyCode;
}
#endregion
#region 驗證碼圖片
/// <summary>
/// 驗證碼圖片 => Bitmap
/// </summary>
/// <param name="verifyCode">驗證碼</param>
/// <param name="width">寬</param>
/// <param name="height">高</param>
/// <returns>Bitmap</returns>
public Bitmap CreateBitmapByImgVerifyCode(string verifyCode, int width, int height)
{
Font font = new Font("Arial", 14, (FontStyle.Bold | FontStyle.Italic));
Brush brush;
Bitmap bitmap = new Bitmap(width, height);
Graphics g = Graphics.FromImage(bitmap);
SizeF totalSizeF = g.MeasureString(verifyCode, font);
SizeF curCharSizeF;
PointF startPointF = new PointF(0, (height - totalSizeF.Height) / 2);
Random random = new Random(); //隨機數產生器
g.Clear(Color.White); //清空圖片背景色
for (int i = 0; i < verifyCode.Length; i++)
{
brush = new LinearGradientBrush(new Point(0, 0), new Point(1, 1), Color.FromArgb(random.Next(255), random.Next(255), random.Next(255)), Color.FromArgb(random.Next(255), random.Next(255), random.Next(255)));
g.DrawString(verifyCode[i].ToString(), font, brush, startPointF);
curCharSizeF = g.MeasureString(verifyCode[i].ToString(), font);
startPointF.X += curCharSizeF.Width;
}
//畫圖片的干擾線
for (int i = 0; i < 10; i++)
{
int x1 = random.Next(bitmap.Width);
int x2 = random.Next(bitmap.Width);
int y1 = random.Next(bitmap.Height);
int y2 = random.Next(bitmap.Height);
g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
}
//畫圖片的前景干擾點
for (int i = 0; i < 100; i++)
{
int x = random.Next(bitmap.Width);
int y = random.Next(bitmap.Height);
bitmap.SetPixel(x, y, Color.FromArgb(random.Next()));
}
g.DrawRectangle(new Pen(Color.Silver), 0, 0, bitmap.Width - 1, bitmap.Height - 1); //畫圖片的邊框線
g.Dispose();
return bitmap;
}
/// <summary>
/// 驗證碼圖片 => byte[]
/// </summary>
/// <param name="verifyCode">驗證碼</param>
/// <param name="width">寬</param>
/// <param name="height">高</param>
/// <returns>byte[]</returns>
public byte[] CreateByteByImgVerifyCode(string verifyCode, int width, int height)
{
Font font = new Font("Arial", 14, (FontStyle.Bold | FontStyle.Italic));
Brush brush;
Bitmap bitmap = new Bitmap(width, height);
Graphics g = Graphics.FromImage(bitmap);
SizeF totalSizeF = g.MeasureString(verifyCode, font);
SizeF curCharSizeF;
PointF startPointF = new PointF(0, (height - totalSizeF.Height) / 2);
Random random = new Random(); //隨機數產生器
g.Clear(Color.White); //清空圖片背景色
for (int i = 0; i < verifyCode.Length; i++)
{
brush = new LinearGradientBrush(new Point(0, 0), new Point(1, 1), Color.FromArgb(random.Next(255), random.Next(255), random.Next(255)), Color.FromArgb(random.Next(255), random.Next(255), random.Next(255)));
g.DrawString(verifyCode[i].ToString(), font, brush, startPointF);
curCharSizeF = g.MeasureString(verifyCode[i].ToString(), font);
startPointF.X += curCharSizeF.Width;
}
//畫圖片的干擾線
for (int i = 0; i < 10; i++)
{
int x1 = random.Next(bitmap.Width);
int x2 = random.Next(bitmap.Width);
int y1 = random.Next(bitmap.Height);
int y2 = random.Next(bitmap.Height);
g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
}
//畫圖片的前景干擾點
for (int i = 0; i < 100; i++)
{
int x = random.Next(bitmap.Width);
int y = random.Next(bitmap.Height);
bitmap.SetPixel(x, y, Color.FromArgb(random.Next()));
}
g.DrawRectangle(new Pen(Color.Silver), 0, 0, bitmap.Width - 1, bitmap.Height - 1); //畫圖片的邊框線
g.Dispose();
//保存圖片數據
MemoryStream stream = new MemoryStream();
bitmap.Save(stream, ImageFormat.Jpeg);
//輸出圖片流
return stream.ToArray();
}
#endregion
}
}
3.創建存儲二維碼的類
[Table("VerifyCode")]
public class VerifyCode : Entity<long>, IHasCreationTime
{
public const int MaxCodeLength = 6;
[Required]
public string Md5Key { get; set; }
[Required]
[MaxLength(MaxCodeLength)]
public string Code { get; set; }
/// <summary>
/// 是否使用
/// </summary>
public bool IsUsed { get; set; }
public DateTime CreationTime { get; set; }
}
4.創建獲取驗證碼的接口
使用VerifyCodeHelper工具類獲取隨機碼，並獲取隨機碼圖片，轉爲base64圖片格式，記錄到數據庫中。
public async Task<VerifyCodeListDto> GetVerify()
{
var code = VerifyCodeHelper.GetSingleObj().CreateVerifyCode(VerifyCodeType.MixVerifyCode); //取隨機碼
var imgCode = VerifyCodeHelper.GetSingleObj().CreateByteByImgVerifyCode(code, 100, 60);
var image = $"data:image/jpeg;base64,{Convert.ToBase64String(imgCode)}";
var verifyCode = new VerifyCode()
{
Md5Key = image,
Code = code,
IsUsed = false
};
var imgEntity = await _verifyCodeRepository.InsertAsync(verifyCode);
await CurrentUnitOfWork.SaveChangesAsync();
return imgEntity.MapTo<VerifyCodeListDto>();
}
僅發送驗證碼的Id和圖片數據。
public class VerifyCodeListDto:EntityDto<long>
{
[Required]
public string Md5Key { get; set; }
}
5.接收到請求時檢查驗證碼，並設置驗證碼爲已使用。
public async Task Check(CreateOrUpdateMemberInput input)
{
//檢查code是否正確
var Code = await _verifyCodeRepository.GetAsync(input.Verify.Id);
TimeSpan dt = DateTime.Now - Code.CreationTime;
if(dt.Minutes>10)
throw new UserFriendlyException("驗證碼十分鐘內有效，該碼已過期");
if (Code.IsUsed ==true)
throw new UserFriendlyException("驗證碼不能重複使用，此碼無效");
if (Code.Code != input.Verify.Code)
throw new UserFriendlyException("驗證碼錯誤");
Code.IsUsed =true;
await _verifyCodeRepository.UpdateAsync(Code)
}
