using (var sha256 = new SHA256Managed()) 
{ 
   // Crypto code here... 
}

public static string GetHash(string text)
{
  using (var sha256 = SHA256.Create())
  {
   var hashedBytes = sha256.ComputeHash(Encoding.UTF8.GetBytes(text));
   return BitConverter.ToString(hashedBytes).Replace("-", "").ToLower();
  }
}

 "dependencies": {
  "System.Security.Cryptography.Algorithms": "4.2.0"
},

using (var md5 = IncrementalHash.CreateHash(HashAlgorithmName.MD5))
{
  md5.AppendData(byteArray1, 0, byteArray1.Length);
  md5.AppendData(byteArray2, 0, byteArray2.Length); 
  var hash = md5.GetHashAndReset();
}

   private static readonly RNGCryptoServiceProvider Rand = new RNGCryptoServiceProvider();

 var rand = new RNGCryptoServiceProvider();

    public interface IRandomNumberProvider
    {
        int Next();
        int Next(int max);
        int Next(int min, int max);
    }

    public class RandomNumberProvider : IRandomNumberProvider
    {
        private readonly RandomNumberGenerator _rand = RandomNumberGenerator.Create();

        public int Next()
        {
            var randb = new byte[4];
            _rand.GetBytes(randb);
            var value = BitConverter.ToInt32(randb, 0);
            if (value < 0) value = -value;
            return value;
        }

        public int Next(int max)
        {
            var randb = new byte[4];
            _rand.GetBytes(randb);
            var value = BitConverter.ToInt32(randb, 0);
            value = value % (max + 1); // % calculates remainder
            if (value < 0) value = -value;
            return value;
        }

        public int Next(int min, int max)
        {
            var value = Next(max - min) + min;
            return value;
        }
    }

    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.TryAddSingleton<IRandomNumberProvider, RandomNumberProvider>();

    public interface IProtectionProvider
    {
        string Decrypt(string inputText);
        string Encrypt(string inputText);
    }

namespace Providers
{
    public class ProtectionProvider : IProtectionProvider
    {
        private readonly IDataProtector _dataProtector;

        public ProtectionProvider(IDataProtectionProvider dataProtectionProvider)
        {
            _dataProtector = dataProtectionProvider.CreateProtector(typeof(ProtectionProvider).FullName);
        }

        public string Decrypt(string inputText)
        {
                var inputBytes = Convert.FromBase64String(inputText);
                var bytes = _dataProtector.Unprotect(inputBytes);
                return Encoding.UTF8.GetString(bytes);
        }

        public string Encrypt(string inputText)
        {
            var inputBytes = Encoding.UTF8.GetBytes(inputText);
            var bytes = _dataProtector.Protect(inputBytes);
            return Convert.ToBase64String(bytes);
        }
    }
}

    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.TryAddSingleton<IProtectionProvider, ProtectionProvider>();

public string Decrypt(string inputText, string key, string salt)
{
    var inputBytes = Convert.FromBase64String(inputText);
    var pdb = new Rfc2898DeriveBytes(key, Encoding.UTF8.GetBytes(salt));
 
    using (var ms = new MemoryStream())
    {
        var alg = Aes.Create();
 
        alg.Key = pdb.GetBytes(32);
        alg.IV = pdb.GetBytes(16);
 
        using (var cs = new CryptoStream(ms, alg.CreateDecryptor(), CryptoStreamMode.Write))
        {
            cs.Write(inputBytes, 0, inputBytes.Length);
        }
        return Encoding.UTF8.GetString(ms.ToArray());
    }
}
 
public string Encrypt(string inputText, string key, string salt)
{
 
    var inputBytes = Encoding.UTF8.GetBytes(inputText);
    var pdb = new Rfc2898DeriveBytes(key, Encoding.UTF8.GetBytes(salt));
    using (var ms = new MemoryStream())
    {
        var alg = Aes.Create();
 
        alg.Key = pdb.GetBytes(32);
        alg.IV = pdb.GetBytes(16);
 
        using (var cs = new CryptoStream(ms, alg.CreateEncryptor(), CryptoStreamMode.Write))
        {
            cs.Write(inputBytes, 0, inputBytes.Length);
        }
        return Convert.ToBase64String(ms.ToArray());
    }
}

1. جداول تعاریف Definition Table
2. جداول ارجاع References Table
3. جداول manifest

DECLARE @IntegerNumber NVARCHAR(100),
@DecimalNumber NVARCHAR(100),
@PointPosition INT =case CHARINDEX('.', @pNumber) WHEN 0 THEN LEN(@pNumber)+1 ELSE CHARINDEX('.', @pNumber) END

SET @IntegerNumber= LEFT(@pNumber, @PointPosition - 1)
SET @DecimalNumber= '?' + SUBSTRING(@pNumber, @PointPosition + 1, LEN(@pNumber))
SET @DecimalNumber=  SUBSTRING(@DecimalNumber,2, len(@DecimalNumber )-PATINDEX('%[^0]%', REVERSE (@DecimalNumber)))

SET @pNumber= @IntegerNumber

DECLARE @Str AS NVARCHAR(2000) = '';
SELECT @Str += REPLACE(REPLACE(LTRIM(RTRIM(nt1.Title + ' ' + nt2.Title + ' ' + nt3.title)),'  ',' '),' ', ' و ')
       + ' ' + pt.title + ' و '
FROM   @MyNumbers  AS mn
       INNER JOIN @PositionTitle pt
            ON  pt.id = mn.id
       INNER JOIN @NumberTitle nt1
            ON  nt1.val = mn.Val1
       INNER JOIN @NumberTitle nt2
            ON  nt2.val = mn.Val2
       INNER JOIN @NumberTitle nt3
            ON  nt3.val = mn.Val3
WHERE  (nt1.val + nt2.val + nt3.val > 0)
ORDER BY pt.id DESC

IF @IntegerNumber='0'  
SET @Str=CASE WHEN PATINDEX('%[^0]%', @DecimalNumber) > 0 THEN @Negative ELSE '' END + 'صفر'
ELSE
SET @Str = @Negative  + LEFT (@Str, LEN(@Str) -2)

DECLARE @PTitle NVARCHAR(100)=ISNULL((SELECT Title FROM @DecimalTitle WHERE id=LEN(@DecimalNumber)),'')
SET @Str += ISNULL(' ممیز '+[dbo].[fnNumberToWord_Persian](@DecimalNumber) +' '+@PTitle,'')
RETURN @str

// RandomGenerator.cs
using System;
using System.Security.Cryptography;

namespace PersianCaptchaHandler
{
    public class RandomGenerator
    {
        private static readonly byte[] Randb = new byte[4];
        private static readonly RNGCryptoServiceProvider Rand = new RNGCryptoServiceProvider();

        public static int Next()
        {
            Rand.GetBytes(Randb);
            var value = BitConverter.ToInt32(Randb, 0);
            if (value < 0) value = -value;
            return value;
        }
        public static int Next(int max)
        {
            Rand.GetBytes(Randb);
            var value = BitConverter.ToInt32(Randb, 0);
            value = value%(max + 1);
            if (value < 0) value = -value;
            return value;
        }
        public static int Next(int min, int max)
        {
            var value = Next(max - min) + min;
            return value;
        }
    }
}

// NumberToString.cs
namespace PersianCaptchaHandler
{
    public class NumberToString
    {

        #region Fields
        private static readonly string[] Yakan = new[] { "صفر", "یک", "دو", "سه", "چهار", "پنج", "شش", "هفت", "هشت", "نه" };
        private static readonly string[] Dahgan = new[] { "", "", "بیست", "سی", "چهل", "پنجاه", "شصت", "هفتاد", "هشتاد", "نود" };
        private static readonly string[] Dahyek = new [] { "ده", "یازده", "دوازده", "سیزده", "چهارده", "پانزده", "شانزده", "هفده", "هجده", "نوزده" };
        private static readonly string[] Sadgan = new [] { "", "یکصد", "دوصد", "سیصد", "چهارصد", "پانصد", "ششصد", "هفتصد", "هشتصد", "نهصد" };
        private static readonly string[] Basex = new [] { "", "هزار", "میلیون", "میلیارد", "تریلیون" };
        #endregion

        private static string Getnum3(int num3)
        {
            var s = "";
            var d12 = num3 % 100;
            var d3 = num3 / 100;
            if (d3 != 0)
                s = Sadgan[d3] + " و ";
            if ((d12 >= 10) && (d12 <= 19))
            {
                s = s + Dahyek[d12 - 10];
            }
            else
            {
                var d2 = d12 / 10;
                if (d2 != 0)
                    s = s + Dahgan[d2] + " و ";
                var d1 = d12 % 10;
                if (d1 != 0)
                    s = s + Yakan[d1] + " و ";
                s = s.Substring(0, s.Length - 3);
            }
            return s;
        }

        public static string ConvertIntNumberToFarsiAlphabatic(string snum)
        {
            var stotal = "";
            if (snum == "0") return Yakan[0];

            snum = snum.PadLeft(((snum.Length - 1) / 3 + 1) * 3, '0');
            var l = snum.Length / 3 - 1;
            for (var i = 0; i <= l; i++)
            {
                var b = int.Parse(snum.Substring(i * 3, 3));
                if (b != 0)
                    stotal = stotal + Getnum3(b) + " " + Basex[l - i] + " و ";
            }
            stotal = stotal.Substring(0, stotal.Length - 3);
            return stotal;
        }
    }
}

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace PersianCaptchaHandler
{
    public class Encryptor
    {
        #region constraints
        private static string Password { get { return "Mehdi"; } }
        private static string Salt { get { return "Payervand"; } }
        #endregion

        public static string Encrypt(string clearText)
        {
            // Turn text to bytes
            var clearBytes = Encoding.Unicode.GetBytes(clearText);

            var pdb = new PasswordDeriveBytes(Password, Encoding.Unicode.GetBytes(Salt));

            var ms = new MemoryStream();
            var alg = Rijndael.Create();

            alg.Key = pdb.GetBytes(32);
            alg.IV = pdb.GetBytes(16);

            var cs = new CryptoStream(ms, alg.CreateEncryptor(), CryptoStreamMode.Write);

            cs.Write(clearBytes, 0, clearBytes.Length);
            cs.Close();

            var encryptedData = ms.ToArray();

            return Convert.ToBase64String(encryptedData);
        }
        public static string Decrypt(string cipherText)
        {
            // Convert text to byte
            var cipherBytes = Convert.FromBase64String(cipherText);

            var pdb = new PasswordDeriveBytes(Password, Encoding.Unicode.GetBytes(Salt));

            var ms = new MemoryStream();
            var alg = Rijndael.Create();

            alg.Key = pdb.GetBytes(32);
            alg.IV = pdb.GetBytes(16);

            var cs = new CryptoStream(ms, alg.CreateDecryptor(), CryptoStreamMode.Write);

            cs.Write(cipherBytes, 0, cipherBytes.Length);
            cs.Close();

            var decryptedData = ms.ToArray();

            return Encoding.Unicode.GetString(decryptedData);
        }
    }
}

// Utils.cs
using System.Text.RegularExpressions;

namespace PersianCaptchaHandler
{
    public class Utils
    {
        private static readonly Regex NumberMatch = new Regex(@"^([0-9]*|\d*\.\d{1}?\d*)$", RegexOptions.Compiled);
        public static bool IsNumber(string number2Match)
        {
            return NumberMatch.IsMatch(number2Match);
        }
    }
}

<add verb="GET" path="/captcha/" type="PersianCaptchaHandler.CaptchaHandler, PersianCaptchaHandler, Version=1.0.0.0, Culture=neutral"  />

<!-- ASPX -->
<dl>
    <dt>تصویر امنیتی</dt>
    <dd>
        <asp:Image ID="imgCaptchaText" runat="server" AlternateText="CaptchaImage" />
        <asp:HiddenField ID="hfCaptchaText" runat="server" />
        <asp:ImageButton ID="btnRefreshCaptcha" runat="server" ImageUrl="/img/refresh.png"
            OnClick="btnRefreshCaptcha_Click" />
        <br />
        <asp:TextBox ID="txtCaptcha" runat="server" AutoCompleteType="Disabled"></asp:TextBox>
    </dd>
    <dd>
        <asp:Button ID="btnSubmit" runat="server" Text="ثبت" OnClick="btnSubmit_Click" />
    </dd>
</dl>
<asp:Label ID="lblMessage" runat="server"></asp:Label>

        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
                SetCaptcha();
        }

        private void SetCaptcha()
        {
            lblMessage.Text =
            txtCaptcha.Text = string.Empty;

            var newNumber =
                RandomGenerator.Next(100, 999)
                ;

            var farsiAlphabatic = NumberToString.ConvertIntNumberToFarsiAlphabatic(newNumber.ToString());

            hfCaptchaText.Value =
                HttpUtility
                .UrlEncode(
                    Encryptor.Encrypt(
                        farsiAlphabatic
                    )
                );

            txtCaptcha.Text = string.Empty;
            imgCaptchaText.ImageUrl =
                "/captcha/?text=" + hfCaptchaText.Value;
        }

        private string GetCaptcha()
        {
            var farsiAlphabatic = NumberToString.ConvertIntNumberToFarsiAlphabatic(txtCaptcha.Text);

            var encryptedString =
                HttpUtility
                .UrlEncode(
                    Encryptor.Encrypt(
                        farsiAlphabatic
                    )
                );

            return encryptedString;
        }

        private bool ValidateUserInputForLogin()
        {
            if (!Utils.IsNumber(txtCaptcha.Text))
            {
                lblMessage.Text = "تصویر امنیتی را بطور صحیح وارد نکرده اید";
                return false;
            }

            var strGetCaptcha =
                GetCaptcha();

            var strDecodedVAlue =
                hfCaptchaText.Value;

            if (strDecodedVAlue != strGetCaptcha)
            {
                lblMessage.Text = "کلمه امنیتی اشتباه است";
                SetCaptcha();
                return false;
            }
            return true;
        }

        protected void btnSubmit_Click(object sender, EventArgs e)
        {
            if (!ValidateUserInputForLogin()) return;
            lblMessage.Text = "کلمه امنیتی درست است";
        }

        protected void btnRefreshCaptcha_Click(object sender, ImageClickEventArgs e)
        {
            SetCaptcha();
        }

Fixed In This Release of Visual Studio 2019 version 16.5

• Modified the find "List View" to work with the VsColorOutput extension.
• Fixed a regression introduced with version 16.5 where use of default indexed properties with value-types caused an internal compiler error.
• Modified find in files to preserve user settings between Visual Studio 2019 sessions.
• Fixed an issue where Goto next/previous entry failed to work in the find results list when "preview selected files in find results" is turned off.
• Fixed an issue with find when doing a regex search a pattern that did not contain regex special characters.
• Fixed the button placement in find in files tool window when its in a docked position. Changed alignments for better experience in docked mode.
• Fixed an issue where the find list view did not navigate to results when enter was hit.
• Fixed an issue where Goto next/previous entry failed to work in the find results list when "preview selected files in find results" is turned off.

Security Advisory Notice

CVE-2020-0899 Microsoft Visual Studio Elevation of Privilege Vulnerability
CVE-2020-0900  Visual Studio Extension Installer Service Elevation of Privilege Vulnerability
CVE-2020-5260  Git for Visual Studio Credential Leak Vulnerability due to insufficient validation on URLs

• DateTime.Now = Cannot provide the value: host value not found
• MSVC codegen error vector reverse_iterator x64 C++17 debug build
• C2440 error building atlenc.h with /permissive- in VS 16.4 Preview 1
• Last Visual Studio update broke NTLM authentication on Android (seems like new version of Momo would be a reason)
• Visual Studio 16.3.1 fails at compiling template code (e.g. from Basler Pylon SDK)
• Using TypeScript 3.7 for IntelliSense
• XCode 11.3 is too new all of a sudden after update to 8.4
• You uploaded an APK or Android App Bundle with invalid or missing signing information for some of its files. You need to create a valid signed APK or Android App Bundle.
• Unable to Run UWP project
• JavaScript IntelliSense not working after update 16.4.1
• Xib : Xcode is to new(rendering problem when using custom components)
• Storyboard error: 'Xcode is too new'
• Stability improvements for debugging watchOS applications.
• Adds Xcode 11.3 SDK support.
• Fixed crash when fstack-protector-strong flag is enabled.
• Fixed some inconsistent behavior with Debugger.

Security Advisory Notice

CVE-2020-0602 ASP.NET Core Denial of Service Vulnerability
CVE-2020-0603 ASP.NET Core Remote Code Execution Vulnerability
CVE-2020-0605 .NET Core Remote Code Execution Vulnerability
CVE-2020-0606 .NET Core Remote Code Execution Vulnerability

Top Issues Fixed in Visual Studio 2019 version 16.4.1

• Fixed "the write operation failed. you must first acquire write access from dataschemamodelcontroller" error trying to publish a database
• Fix ExecutionEngineException exceptions when using SignalR on iOS devices in some configurations
• Runtime Fix "CEE_RET: value type stack" crash when interpreter was enabled with some libraries
• TypeScript 3.7.3 is now included by default, which contains several fixes for issues that effect the JavaScript and TypeScript editing experience.
• May allow mitigation of a Per-Monitor awareness related crash in Visual Studio

Security Advisory Notice

CVE-2019-1349 Git for Visual Studio Remote Excecution Vulnerability due to too lax restrictions on submodule names

CVE-2019-1350 Git for Visual Studio Remote Excecution Vulnerability due to incorrect quoting of command-line arguments

CVE-2019-1351 Git for Visual Studio Arbitrary File Overwrite Vulnerability due to usage of non-letter drive names during clone

CVE-2019-1352 Git for Visual Studio Remote Excecution Vulnerability due to unawareness of NTFS Alternate Data Streams

CVE-2019-1354 Git for Visual Studio Arbitrary File Overwrite Vulnerability due to not refusing to write out tracked files containing backslashes

CVE-2019-1387 Git for Visual Studio Remote Execution Vulnerability due to too lax validation of submodule names in recursive clones

CVE-2019-1486 Live Share extension URL redirection vulnerability

These are the customer-reported issues addressed in 15.9.7:

• Crashes when expanding variables!.
• /DEBUG:FASTLINK + C7 + PCH crashes debugger.
• Native C++ application crashes because of stack corruption with VS 2017 15.9.2.
• Incorrect Release Mode code.
• Xamarin Unobserved Task Exception WebRequest.
• Link /SOURCELINK option seems to do nothing. This fixes Source Link for Managed C++ Debugging.
• Fixed an issue with corruption of AVX/MPX/AVX512 registers while Debugging.
• Update of Microsoft.VCLibs.140.00.UWPDestkop framework packages for C++ UWP DesktopBridge applications adding support for ARM64.
• Corrected incorrect version of VCToolsRedistVersion in Microsoft.VCToolsVersion.default.props.
• Corrected unsigned embedded dll for VC Redist installers.
• SSDT/Web Tools: We fixed an issue where SQL LocalDB was not installed on Polish, Turkish, and Czech locales.
• SSDT: We fixed an issue affecting SQL Server Analysis Services (Method not found exception when clicking on UI).
• SSDT: We fixed an accessibility issue which was causing the contents of a table not to be visible in the result window when using High-Contrast mode.

Security Advisory Notices

• WorkflowDesigner XOML deserialization allows code execution.
• .NET Framework and Visual Studio Spoofing Vulnerability.