The lack of XOR Drawing feature in GDI+ was not certainly welcome in the programmer's community. I guess it will be hard to survive with this handicap. In spite of this, I would like to show how we can draw rubber-band lines and shapes in GDI+ with just a few lines of code.

     Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) 
    Dim size As Size = SystemInformation.PrimaryMonitorMaximizedWindowSize 
    bitmap = New Bitmap(size.Width, size.Height) 
    gB = Graphics.FromImage(bitmap) 
    Dim bckColor As Color = Me.BackColor 
    gB.Clear(bckColor) 
    End Sub 
    Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.MouseEventArgs) 
    Dim p As Point = New Point(e.X, e.Y) 
    x0 = p.X 
    y0 = p.Y 
    drag = True 
    End Sub 
    Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.MouseEventArgs) 
    Dim p As Point = New Point(e.X, e.Y) 
    x= p.X 
    y = p.Y 
    Dim cx As Integer = x - x0 
    Dim cy As Integer = y - y0 
    If drag Then 
    Dim gx As Graphics = CreateGraphics() 
    gx.DrawImage(bitmap, 0, 0) 
    gx.Dispose() 
    Dim g As Graphics = CreateGraphics() 
    Dim pen As Pen = New Pen(Color.Blue) 
    Select Case DrawMode 
    Case 1 
    g.DrawLine(pen, x0, y0, x, y) 
    Exit Select 
    Case 2 
    g.DrawEllipse(pen, x0, y0, cx, cy) 
    Exit Select 
    Case 3 
    g.DrawRectangle(pen, x0, y0, cx, cy) 
    Exit Select 
    End Select 
    g.Dispose() 
    pen.Dispose() 
    End If 
    End Sub 
    Private Sub Form1_MouseUp(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.MouseEventArgs) 
    Dim cx As Integer = x - x0 
    Dim cy As Integer = y - y0 
    Dim pen As Pen = New Pen(Color.Blue) 
    Select Case DrawMode 
    Case 1 
    gB.DrawLine(pen, x0, y0, x, y) 
    Exit Select 
    Case 2 
    gB.DrawEllipse(pen, x0, y0, cx, cy) 
    Exit Select 
    Case 3 
    gB.DrawRectangle(pen, x0, y0, cx, cy) 
    Exit Select 
    End Select 
    drag = False 
    pen.Dispose() 
    End Sub 
    Private Sub Form1_Paint(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.PaintEventArgs) 
    Dim gx As Graphics = CreateGraphics() 
    gx.DrawImage(bitmap, 0, 0) 
    gx.Dispose() 
    End Sub 
    Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)button1.ForeColor = Color.Red 
    button2.ForeColor = Color.Black 
    button3.ForeColor = Color.Black 
    DrawMode = 1 
    End Sub 
    Private Sub button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) 
    button2.ForeColor = Color.Red 
    button1.ForeColor = Color.Black 
    button3.ForeColor = Color.Black 
    DrawMode = 2 
    End Sub 
    Private Sub button3_Click(ByVal sender As Object, ByVal e As System.EventArgs) 
    button3.ForeColor = Color.Red 
    button1.ForeColor = Color.Black 
    button2.ForeColor = Color.Black 
    DrawMode = 3 
    End Sub 
    Private Sub panel1_Paint(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.PaintEventArgs) 
    button1.ForeColor = Color.Red 
    button1.Focus() 
    End Sub

The lack of XOR Drawing feature in GDI+ was not certainly welcome in the programmer's community.

I guess it will be hard to survive with this handicap. In spite of this, I would like to show how we can draw rubber-band lines and shapes in GDI+ with just a few lines of code.

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) 
    Dim size As Size = SystemInformation.PrimaryMonitorMaximizedWindowSize 
    bitmap = New Bitmap(size.Width, size.Height) 
    gB = Graphics.FromImage(bitmap) 
    Dim bckColor As Color = Me.BackColor 
    gB.Clear(bckColor) 
    End Sub 
    Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.MouseEventArgs) 
    Dim p As Point = New Point(e.X, e.Y) 
    x0 = p.X 
    y0 = p.Y 
    drag = True 
    End Sub 
    Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.MouseEventArgs) 
    Dim p As Point = New Point(e.X, e.Y) 
    x= p.X 
    y = p.Y 
    Dim cx As Integer = x - x0 
    Dim cy As Integer = y - y0 
    If drag Then 
    Dim gx As Graphics = CreateGraphics() 
    gx.DrawImage(bitmap, 0, 0) 
    gx.Dispose() 
    Dim g As Graphics = CreateGraphics() 
    Dim pen As Pen = New Pen(Color.Blue) 
    Select Case DrawMode 
    Case 1 
    g.DrawLine(pen, x0, y0, x, y) 
    Exit Select 
    Case 2 
    g.DrawEllipse(pen, x0, y0, cx, cy) 
    Exit Select 
    Case 3 
    g.DrawRectangle(pen, x0, y0, cx, cy) 
    Exit Select 
    End Select 
    g.Dispose() 
    pen.Dispose() 
    End If 
    End Sub 
    Private Sub Form1_MouseUp(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.MouseEventArgs) 
    Dim cx As Integer = x - x0 
    Dim cy As Integer = y - y0 
    Dim pen As Pen = New Pen(Color.Blue) 
    Select Case DrawMode 
    Case 1 
    gB.DrawLine(pen, x0, y0, x, y) 
    Exit Select 
    Case 2 
    gB.DrawEllipse(pen, x0, y0, cx, cy) 
    Exit Select 
    Case 3 
    gB.DrawRectangle(pen, x0, y0, cx, cy) 
    Exit Select 
    End Select 
    drag = False 
    pen.Dispose() 
    End Sub 
    Private Sub Form1_Paint(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.PaintEventArgs) 
    Dim gx As Graphics = CreateGraphics() 
    gx.DrawImage(bitmap, 0, 0) 
    gx.Dispose() 
    End Sub 
    Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)button1.ForeColor = Color.Red 
    button2.ForeColor = Color.Black 
    button3.ForeColor = Color.Black 
    DrawMode = 1 
    End Sub 
    Private Sub button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) 
    button2.ForeColor = Color.Red 
    button1.ForeColor = Color.Black 
    button3.ForeColor = Color.Black 
    DrawMode = 2 
    End Sub 
    Private Sub button3_Click(ByVal sender As Object, ByVal e As System.EventArgs) 
    button3.ForeColor = Color.Red 
    button1.ForeColor = Color.Black 
    button2.ForeColor = Color.Black 
    DrawMode = 3 
    End Sub 
    Private Sub panel1_Paint(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.PaintEventArgs) 
    button1.ForeColor = Color.Red 
    button1.Focus() 
    End Sub

An instructor I once had made a statement that has echoed in my head for years. When you are a programmer, you have two groups of end users, the people who will actually use the software, AND other programmers who may someday have to modify your code. With that in mind, I have always tried to write my code to be as easily readable to other programmers as possible.

Visual Studio .NET gives us some very handy tools to improve readability in our code. One that I am particularly fond of is the #region directive that allows us to collapse code in a customized manor.

Regions are created in this format,
#region MyRegion

your code here
#EndRegion

Everything that falls within the directives will be collapsible.

The method I've chosen to adapt is to create regions for each different type of element in a class (i.e. constructors, variables, methods, properties, enumerators) so that my code can be easily navigated.

Here is an example,

Visual Studio Shortcut Keys and Tips

Today, in this article, we shall see what namespace actually does and how to organize the classes using namespaces. We use namespaces to organize classes into a logically related hierarchy. Namespaces function as both an internal system for organizing our application and an external way to avoid name collision between source code and application. Because more than one company may create a class with the same name, such as Employee, when we create code, that may be seen or used by third parties. It’s highly recommended that we shall organize our classes by using a hierarchy of namespaces. By practising this, we can avoid interoperability issues on application.

To create a namespace, we simply type a keyword namespace followed by the name. It is recommended to use Pascal case for namespaces.

It is also recommended that you create at least two-tiered namespaces, which is one that contains two levels of classification, separated by a period.

Let us see sample example of a two-tiered namespace.

Above two-tiered namespace declaration is identical to writing each namespace in nested format, as shown in the following code. 

In both cases, we refer to class by using the following code.

Note

We should avoid creating a class with the same name as namespace.

Commonly used namespaces in .NET Framework
Microsoft .NET Framework is made of many namespaces, the most important one being System. The System namespace contains classes that most of the applications use to interact with operating system.

For example, the system namespace contains the console class which provides several methods, including WriteLine, which is a command that enables us to write code to an on-screen console.

We can access WriteLine method of console as follows.

A few of other namespaces that are provided by .NET Framework through the system namespace are listed below. 

• System.Windows.Forms
  Provides the classes that are useful for building applications based on windows. 

Visual Studio 2017 v15.3 or higher versions support Live Unit Testing. This feature executes the already-written test cases automatically as a programmer makes the code changes. Live Unit Testing helps a developer to do the following:

• It executes all the impacted Test Cases as a programmer modifies the code and makes sure changes do not break Unit Test Cases.
• Through the Visual Studio editor, the programmer sees the code coverage in a realistic view.
• It also indicates which line is covered or not using Live Unit Testing.
• Live Unit Testing is supported in  both .NET Framework and .NET Core.

Enabling
Live Unit Testing is only available in Visual Studio 2017 with the Enterprise edition. We can enable the Live Unit Testing by going to the following menus - Test > Live Unit Testing > Start.

After enabling the Live Unit Testing for a project, Live Unit Testing shows options as Start, Pause, Stop and Reset.

Configuration
The default configuration can be changed from the Visual Studio Menu Tool > Options > Live Unit Testing > General. We can configure the Live Unit Testing for the Battery and Memory usages, Testcase Timeout, and Logging Level can be set as needed.

Setup Project Solution

• Open the Visual Studio 2017.
• Create one Windows Library Project as “ClassLibrary1” and Change the “Class1.cs” to the “AreaCalculator.cs”.
• Right click on the solution and add a Unit Test Project as “UnitTestProject1” and change the “UnitTest1.cs” to the “AreaCalculatorTest.cs”
• Add the Reference of the “ClassLibrary1” project to the “UnitTestProject1”.
• Add the using statement “using ClassLibrary1;” to the “AreaCalculatorTest.cs” in the using statement section.
• Build the Solution.

Demo
Open the AreaCalculator.cs and add the code as per the below screenshot.
Open the AreaCalculatorTest.cs and paste the below code. I have not added the Test Method for the triangle’s area calculation and incorrectly calculated the Test Method of the square’s area, just to show some behavior of Live Unit Testing.

Replace the below code in the AreaCalculatorTest.cs file
Now start the Live Unit Testing from the Test menu, then an automatic background process triggers and we see an icon in-line with code. Description of each icon is mentioned here

• Green Tick Mark represents that this Method is covered for the unit testing.
• Cross Mark represents that this method is covered for the unit testing, but the test case failed during execution.
• Blue Negative Mark represent that this method is not covered for the unit testing so a test case needs to be created.

Below screenshots represent each icon of the Live Unit Testing

Icon’s in AreaCalculator.cs

Icon’s in AreaCalculatorTest.cs

So, with the help of Live Unit Testing of Visual Studio, a developer will know about the impact of the changes he is making, and if it's covered for unit testing or not. This is an awesome feature of Visual Studio 2017

The BackgroundWorker allows you to execute operations that take a long period of time such as database transaction or file downloads, asynchronously on a separate thread and allow the user interface to remain responsive.

Start an Operation in the Background
First, you need to add an instance of the BackgroundWorker component to your application, if you use visual studio, just drag it from the toolbox to your application or you can create it manually as follow:
BackgroundWorker backgroundWorker1 = new BackgroundWorker(); 

To start the operation in the background you have to call the RunWorkerAsync() method of the BackgroundWorker, when you call this method the BackgroundWroker starts the execution of the background operation by raising the DoWork event, the code in the DoWork event handler is executed on a separate thread.
BackgroundWorker backgroundWorker1 = new BackgroundWorker(); 
//start the operation on another thread 
private void btnStart_Click(object sender, EventArgs e) 
{ 
    backgroundWorker1.RunWokerAsync(); 
} 
//DoWork event handler is executed on a separate thread 
private void backgroundWorker1_DoWork(object sender, DoWorkeventArgs e) 
{ 
    //a long running operation 
    Thread.Sleep(5000); 
} 

You can send a parameter to the background operation using the RunWorkerAsync() method. You can receive this parameter by using the Argument property of the instance of DoWorkEventArgs in the DoWork event handler then you cast it to use it in the background operation.

BackgroundWorker backgroundWorker1 = new BackgroundWorker(); 
//start the operation on another thread 
private void btnStart_Click(object sender, EventArgs e) 
{ 
    backgroundWorker1.RunWokerAsync(2000); 
} 
//DoWork event handler is executed on a separate thread 
private void backgroundWorker1_DoWork(object sender, DoWorkeventArgs e) 
{ 
    int input = (int)e.Argument; 
    //a long running operation 
    Thread.Sleep(input); 
} 

Reporting progress of a background operation using BackgroundWorker
By using the BackgroundWorker you have the ability to report progress updates of the executing operation. To use this options you must set the WorkerReportsProgress to true.

To start report progress you call ReportProgress() method and use it to pass a parameter that have the value of the percentage of the progress that have been completed. This method raises the BackgroundWorker.ProgressChanged event. In the event handler of the ProgressChanged you can recieve the value of the progress precentage on the main thread using the ProgressPercentage property of the instance of ProgressChangedEventArgs.

BackgroundWorker backgroundWorker1 = new BackgroundWorker(); 
backgroundWorker1.WorkerReportsProgress = true; 
//start the operation on another thread 
private void btnStart_Click(object sender, EventArgs e) 
{ 
    backgroundWorker1.RunWokerAsync(); 
} 
//DoWork event handler is executed on a separate thread 
private void backgroundWorker1_DoWork(object sender, DoWorkeventArgs e) 
{ 
    //a long running operation 
    for (int i = 1; i < 11; i++) 
    {    
        Thread.Sleep(2000); 
        backgroundWorker1.ReportProgress(i*10); 
    } 
} 
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e) 
{ 
    progressBar1.value = e.ProgressPercentage; 
} 

Canceling a background operation using BackgroundWorker
With the BackgroundWorker you have the ability to cancel the background operation, to do this you first must set WorkerSupportsCancellation property to true.

The next step is to call the CancelAsync() method by doing so you set the CancellationPending property to true, by polling the CancellationPending property you can determine whether or not to cancel the background operation.

BackgroundWorker backgroundWorker1 = new BackgroundWorker(); 
backgroundWorker1.WorkerSupportsCancellation = true; 
//start the operation on another thread 
private void btnStart_Click(object sender, EventArgs e) 
{ 
    backgroundWorker1.RunWokerAsync(); 
} 
//a buttun to cancel the operation 
private void btnCancel_Click(object sender, EventArgs e) 
{ 
    backgroundWorker1.CancelAsync(); 
} 
//DoWork event handler is executed on a separate thread 
private void backgroundWorker1_DoWork(object sender, DoWorkeventArgs e) 
{ 
    //a long running operation 
    for (int i = 1; i < 11; i++) 
    { 
        Thread.Sleep(2000); 
        backgroundWorker1.ReportProgress(i*10); 
        if(backgroundWorker1.CancellationPending) 
        { 
            e.cancel = true; 
            return; 
        } 
    } 
} 

Alert the user in the completion of the background operation
When the background operation completes, whether because the background operation is completed or canceled, the RunWorkerCompleted event is raised. You can alert the user to the completion by handling the RunWorkerCompleted event.

You can determine if the user canceled the operation by using the Cancelled property of the instance RunWorkerCompletedEventArgs.
BackgroundWorker backgroundWorker1 = new BackgroundWorker(); 
//start the operation on another thread 
private void btnStart_Click(object sender, EventArgs e) 
{ 
    backgroundWorker1.RunWokerAsync(); 
} 
//a buttun to cancel the operation 
private void btnCancel_Click(object sender, EventArgs e) 
{ 
    backgroundWorker1.CancelAsync(); 
}  
//DoWork event handler is executed on a separate thread 
private void backgroundWorker1_DoWork(object sender, DoWorkeventArgs e) 
{ 
    //a long running operation 
    for (int i = 1; i < 11; i++) 
    { 
        Thread.Sleep(2000); 
        backgroundWorker1.ReportProgress(i*10); 
        if (backgroundWorker1.CancellationPending) 
        { 
            e.Cancel = true; 
            return; 
        } 
    } 
}  
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) 
{ 
    if(e.Cancelled) 
    { 
        MessageBox.Show("Operation Cancelled"); 
    } 
    else 
    { 
        MessageBox.Show("OperationCompleted"); 
    } 
} 

Return a value from the background operation
You can return a value from the background operation that in the DoWork event handler using the Result property of the DoWorkEventArgs instance, and you can receive it in the RunWorkerCompleted event handler using the Result property of the RunWorkerCompletedEventArgs instance.

BackgroundWorker backgroundWorker1 = new BackgroundWorker(); 
//start the operation on another thread 
private void btnStart_Click(object sender, EventArgs e) 
{ 
    backgroundWorker1.RunWokerAsync(); 
} 
//DoWork event handler is executed on a separate thread 
private void backgroundWorker1_DoWork(object sender, DoWorkeventArgs e) 
{ 
    //a long running operation here 
    Thread.Sleep(2000); 
    //return the value here 
    e.Result = 10; 
} 
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) 
{ 
    //recieve the return value here 
    int returnValue = (int)e.Result; 
} 

Recently, Microsoft has announced the availability of Preview of Visual Studio IntelliCode in its Build 2018 developer’s conference. This is a new experimental tool for Visual Studio users bringing more of the company’s artificial intelligence smart to software development.

A couple of months ago, I started using Visual Studio Code for my development activities. I found myself very uncomfortable with the keys and shortcuts. I have been using Visual Studio for more than 6 years now. So, I was very comfortable with the keys and shortcuts of that. The difference in shortcuts was creating a challenge for me. Should I remember a different set of shortcuts for VS Code? Should I start using some other editor?

Then, I started to customize the VS Code shortcuts. If you are also facing the same issues, then it's time you should consider customizing the Visual Studio Code shortcuts. It’s not worth spending energy on remembering a new set of shortcuts for a specific editor. Following are some tips,

1. Open keyboard shortcuts in Visual Studio Code and update the shortcuts as per your need.
   Press ctrl+K, ctrl+s to open the keyboard shortcut window. This looks something like below.



2. You can see the Edit button on the right side of the row (highlighted one). On click of the Edit button, it will ask you to change the combination you want to execute the command for.
   

   

   You can change the combination for your convenience.

1. You can open keybindings.json file and update as per your need.
   To open the keybindings.json, you need to open the Keyboard shortcuts first by pressing ctrl+k, ctrl+s. You can click on the keybindings.json file.



2. This will open the default keybindings. This is a JSON file which can be modified to get your desired shortcuts.

1. You can have your custom JSON file with your shortcut commands.
   When you open default keybindings.json file in the right-hand side window, it opens a keybindings.json file where you can write your custom keys and commands.
   

   

Given are a couple of commands I have added in the keybindings.json file to work with the VS Code. Please let me know your feedbacks/ comments. Are there better ways I am not just aware of?