New features added in C# 5.0

C# most recent version 5.0 was released on August 15, 2012 with .NET Framework 4.5 and Visual Studio 2012.

There are two main features in C# 5.0 - Async Programming and Caller Information. Let's understand both these features in details as given below.

Async Feature (Asynchronous Methods)

C# 5.0 Async feature introduces two keywords async and await which allows you to write asynchronous code more easily and intuitively like as synchronous code. Before C# 5.0, for writing an asynchronous code, you need to define callbacks (also known as continuations) to capture what happens after an asynchronous process finishes. This makes your code and other routine task such exception handling complicated.

Both the keywords are used in a combination of each other. Hence, an await operator is applied to a one or more than one expressions of an async method. An async method returns a Task or Task<TResult> that represents the ongoing work of the method. The task contains information that the caller of the asynchronous method can use, such as the status of the task, its unique ID, and the method's result.

public async Task<IEnumerable<Product>> GetProductList()
{
 HttpClient client = new HttpClient();
 Uri address = new Uri("http://dotnet-tricks.com/");
 client.BaseAddress = address;
 
 HttpResponseMessage response = await client.GetAsync("myservice/product/ProductList");
 
 if (response.IsSuccessStatusCode)
 {
 var list = await response.Content.ReadAsAsync<IEnumerable<Product>>();
 return list;
 }
 else
 {
 return null;
 }
}

Caller Information (Caller info attributes)

Caller Information can help you in tracing, debugging and creating diagnose tools. It will help you to avoid duplicate codes which are generally invoked in many methods for same purpose, such as logging and tracing.

You could get the following information of caller method:

1. 
   

   CallerFilePathAttribute

   
   

   Full path of the source file that contains the caller. This is the file path at compile time.

   
   
2. 
   

   CallerLineNumberAttribute

   
   

   Line number in the source file at which the method is called.

   
   
3. 
   

   CallerMemberNameAttribute

   
   

   Method or property name of the caller.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
 
class Example
{
 static void Main(string[] args)
 {
 Console.WriteLine("Main method Start");
 InsertLog("Main");
 MyMethodB();
 MyMethodA();
 Console.WriteLine("Main method End!");
 Console.ReadLine(); // hold on result
 }
 
 static void MyMethodA()
 {
 InsertLog("MyMethodA");
 MyMethodB();
 }
 
 static void MyMethodB()
 {
 // some code here. 
 }
 
 static void InsertLog(string method)
 {
 Console.WriteLine("{0} called MyMethodB at {1}", method,
 DateTime.Now);
 }
}
/* Output:
 Main method Start
 Main called MyMethodB at 11/17/2013 11:12:24 PM
 MyMethodA called MyMethodB at 11/17/2013 11:12:24 PM
 Main method End!
*/

In both Main and MyMethodA, method InsertLog is invoked for logging. Now we can change the above code as follows.

using System;
using System.Collections.Generic;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;
 
class Example
{
 static void Main(string[] args)
 {
 Console.WriteLine("Main method Start");
 MyMethodB();
 MyMethodA();
 Console.WriteLine("Main method End!");
 Console.ReadLine();
 }
 
 static void MyMethodA()
 {
 MyMethodB();
 }
 
 static void MyMethodB([CallerMemberName] string memberName = "", [CallerFilePath] string sourceFilePath = "", [CallerLineNumber] int sourceLineNumber = 0)
 {
 InsertLog(memberName);
 }
 
 static void InsertLog(string method)
 {
 Console.WriteLine("{0} called MyMethodB at {1}", method, DateTime.Now);
 }
}
 
/*Output:
 Main method Start
 Main called MyMethodB at 11/17/2013 10:30:11 PM
 MyMethodA called MyMethodB at 11/17/2013 10:30:11 PM
 Main method End!
 */

Hope you like these new features of C# 5.0.

How to change the root password for MySQL in XAMPP?

By default, when you install XAMPP in your windows machine, the root password for the MySQL is set to empty. But this is not recommended, as the MySQL database without a password will be accessible to everyone. To avoid this, a proper/secure password must be set to the user root. To do it in XAMPP, there are two ways.

Method 1: reset XAMPP MySQL root password through web interface:

After you started your XAMPP server, go to the browser and type the URL http://localhost/security/ (incase you've modified XAMPP server port, you need to include that port number also in previous URL). The security page will be shown where you can change the root password for MySQL. This will update the phpMyAdmin config also.

Method 2: reset XAMPP MySQL root password through SQL update:

1. Start the Apache Server and MySQL instances from the XAMPP control panel.
2. After the server started, open any web browser and give http://localhost:8090/phpmyadmin/ (if you are running XAMPP on 8090 port). This will open the phpMyAdmin interface. Using this interface we can manager the MySQL server from the web browser.
3. In the phpMyAdmin window, select SQL tab from the right panel. This will open the SQL tab where we can run the SQL queries.
4. Now type the following query in the textarea and click Go
   UPDATE mysql.user SET Password=PASSWORD('password') WHERE User='root'; FLUSH PRIVILEGES;
5. Now you will see a message saying that the query has been executed successfully.
6. If you refresh the page, you will be getting a error message. This is because the phpMyAdmin configuration file is not aware of our newly set root passoword. To do this we have to modify the phpMyAdmin config file.
7. Open the file [XAMPP Installation Path] / phpmyadmin / config.inc.php in your favorite text editor.
8. Search for the string $cfg\['Servers'\]\[$i\]['password'] = ''; and change it to like this, $cfg\['Servers'\]\[$i\]['password'] = 'password'; Here the 'password' is what we set to the root user using the SQL query.
9. Now all set to go. Save the config.inc.php file and restart the XAMPP server.