Some key areas of focus uncovered by this investigation were:
Being mindful of memory allocations to minimize GC pause times
Keeping long-running calls non-blocking/asynchronous
Minimizing calls to external resources (such as other web services or the database) with caching and grouping of requests
In this short video Nate shows us how to use Entity Framework 7 in a cross platform way (on a mac in this case). One of the guiding principles (as outlined by Rowan in an earlier video) was the ability to use EF7 on any kind of device. This video shows the culmination of that work.
//It's only for code review purpose!
using System.Data;
using System.Data.SqlClient;
using System.Web.Configuration;
public sealed class SqlHelper
{
private SqlHelper() { }
// Send Connection String
//---------------------------------------------------------------------------------------
public static string GetCntString()
{
return WebConfigurationManager.ConnectionStrings["db_ConnectionString"].ConnectionString;
}
// Connect to Data Base SqlServer
//---------------------------------------------------------------------------------------
public static SqlConnection Connect2Db(ref SqlConnection sqlCnt, string cntString)
{
try
{
if (sqlCnt == null) sqlCnt = new SqlConnection();
sqlCnt.ConnectionString = cntString;
if (sqlCnt.State != ConnectionState.Open) sqlCnt.Open();
return sqlCnt;
}
catch (SqlException)
{
return null;
}
}
// Run ExecuteScalar Command
//---------------------------------------------------------------------------------------
public static string RunExecuteScalarCmd(ref SqlConnection sqlCnt, string strCmd, bool blnClose)
{
Connect2Db(ref sqlCnt, GetCntString());
using (sqlCnt)
{
using(SqlCommand sqlCmd = sqlCnt.CreateCommand())
{
sqlCmd.CommandText = strCmd;
object objResult = sqlCmd.ExecuteScalar();
if (blnClose) CloseCnt(ref sqlCnt, true);
return (objResult == null) ? string.Empty : objResult.ToString();
}
}
}
// Close SqlServer Connection
//---------------------------------------------------------------------------------------
public static bool CloseCnt(ref SqlConnection sqlCnt, bool nullSqlCnt)
{
try
{
if (sqlCnt == null) return true;
if (sqlCnt.State == ConnectionState.Open)
{
sqlCnt.Close();
sqlCnt.Dispose();
}
if (nullSqlCnt) sqlCnt = null;
return true;
}
catch (SqlException)
{
return false;
}
}
}
protected void BtnTest_Click(object sender, EventArgs e)
{
SqlConnection sqlCnt = new SqlConnection();
string strQuery = "SELECT COUNT(UnitPrice) AS PriceCount FROM [Order Details]";
// در این مرحله پارامتر سوم یعنی کانکشن باز نگه داشته شود
string strResult = SqlHelper.RunExecuteScalarCmd(ref sqlCnt, strQuery, false);
strQuery = "SELECT LastName + N'-' + FirstName AS FullName FROM Employees WHERE (EmployeeID = 9)";
// در این مرحله پارامتر سوم یعنی کانکشن بسته شود
strResult = SqlHelper.RunExecuteScalarCmd(ref sqlCnt, strQuery, true);
}
/// <summary>
///
/// </summary>
/// <param name="sqlCnt"></param>
/// <param name="cntString"></param>
/// <returns></returns>
public static SqlConnection Connect2Db(ref SqlConnection sqlCnt, string cntString)
Microsoft plugged as many as 89 security flaws as part of its monthly Patch Tuesday updates released today, including fixes for an actively exploited zero-day in Internet Explorer that could permit an attacker to run arbitrary code on target machines.
Rider EAP 20 fixes a number of bugs, improves .NET Core support, has better NuGet performance, supports Xamarin Android applications, comes with Node.js tooling from WebStorm (including SpyJS), can generate ResX files, executes T4 templates (needs Windows and Visual Studio SDK), adds support for scratch files, … Too much for one sentence, as you can see from the full list of fixes. We’ll highlight a few, read on!
The next stop for .NET 7 is General Availability, one month out, as Microsoft today shipped .NET 7 Release Candidate 2.
Tap is a Javascript library for easy unified handling of user interactions such as mouse, touch and pointer events.
Tap handles this for you
public class User
{
public string Name { set; get; }
} public record User
{
public string Name { set; get; }
} var user = new User(); user.Name = "User 1";
public record User(string Name);
var user = new User("User 1");
// Error: Init-only property or indexer 'User.Name' can only be assigned
// in an object initializer, or on 'this' or 'base' in an instance constructor
// or an 'init' accessor. [CS9Features]csharp(CS8852)
user.Name = "User 1"; public record User(string Name);
using System;
using System.Collections.Generic;
using System.Runtime.CompilerServices;
using System.Text;
using CS9Features;
public class User : IEquatable<User>
{
protected virtual Type EqualityContract
{
[System.Runtime.CompilerServices.NullableContext(1)]
[CompilerGenerated]
get
{
return typeof(User);
}
}
public string Name
{
get;
set/*init*/;
}
public User(string Name)
{
this.Name = Name;
base..ctor();
}
public override string ToString()
{
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append("User");
stringBuilder.Append(" { ");
if (PrintMembers(stringBuilder))
{
stringBuilder.Append(" ");
}
stringBuilder.Append("}");
return stringBuilder.ToString();
}
protected virtual bool PrintMembers(StringBuilder builder)
{
builder.Append("Name");
builder.Append(" = ");
builder.Append((object?)Name);
return true;
}
[System.Runtime.CompilerServices.NullableContext(2)]
public static bool operator !=(User? r1, User? r2)
{
return !(r1 == r2);
}
[System.Runtime.CompilerServices.NullableContext(2)]
public static bool operator ==(User? r1, User? r2)
{
return (object)r1 == r2 || (r1?.Equals(r2) ?? false);
}
public override int GetHashCode()
{
return EqualityComparer<Type>.Default.GetHashCode(EqualityContract) * -1521134295 + EqualityComparer<string>.Default.GetHashCode(Name);
}
public override bool Equals(object? obj)
{
return Equals(obj as User);
}
public virtual bool Equals(User? other)
{
return (object)other != null && EqualityContract == other!.EqualityContract && EqualityComparer<string>.Default.Equals(Name, other!.Name);
}
public virtual User <Clone>$()
{
return new User(this);
}
protected User(User original)
{
Name = original.Name;
}
public void Deconstruct(out string Name)
{
Name = this.Name;
}
} public virtual User <Clone>$()
{
return new User(this);
} public record User(string Name, int Age);
var user1 = new User("User 1", 21); var user2 = user1 with { Age = 31 }; var user1 = new User("User 1", 21);
var user2 = new User("User 1", 21); Console.WriteLine("user1.Equals(user2) -> {0}", user1.Equals(user2));
Console.WriteLine("user1 == user2 -> {0}", user1 == user2); user1.Equals(user2) -> True user1 == user2 -> True
public virtual bool Equals(User? other)
{
return (object)other != null &&
EqualityContract == other!.EqualityContract &&
EqualityComparer<string>.Default.Equals(Name, other!.Name) &&
EqualityComparer<int>.Default.Equals(Age, other!.Age);
} public record User
{
public string Name { get; init; }
public User(string name)
{
Name = name;
}
}
public record UserWithAge : User
{
public int Age { get; init; }
public UserWithAge(string name, int age) : base(name)
{
Age = age;
}
} var user1 = new User("User 1");
var user2 = new UserWithAge("User 1", 21);
Console.WriteLine("user1.Equals(user2) -> {0}", user1.Equals(user2));
Console.WriteLine("user1 == user2 -> {0}", user1 == user2); user1.Equals(user2) -> False user1 == user2 -> False
public abstract record Food(int Calories); public record Milk(int C, double FatPercentage) : Food(C);
Console.WriteLine(user1.ToString()); Console.WriteLine(user2.ToString());
User { Name = User 1 }
UserWithAge { Name = User 1, Age = 21 } public record Person(string Name, int Age);
public void Deconstruct(out string Name, out int Age)
{
Name = this.Name;
Age = this.Age;
} var (name, age) = new Person("User 1", 21); public record Person([Required] string Name, [Range(0, 150)] int Age);
public class PersonController
{
public IActionResult Index() => View();
[HttpPost]
public IActionResult Index(Person person)
{
// ...
}
}