Tutorial: Create a new WinForms app (Windows Forms .NET)

In this short tutorial, you'll learn how to create a new Windows Forms (WinForms) app with Visual Studio. Once the initial app has been generated, you'll learn how to add controls and how to handle events. By the end of this tutorial, you'll have a simple app that adds names to a list box.

Important

The Desktop Guide documentation for .NET 5 (and .NET Core) is under construction.

In this tutorial, you learn how to:

  • Create a new WinForms app
  • Add controls to a form
  • Handle control events to provide app functionality
  • Run the app

Prerequisites

Create a WinForms app

The first step to creating a new app is opening Visual Studio and generating the app from a template.

  1. Open Visual Studio.

  2. Select Create a new project.

    Create a new Windows Forms project in Visual Studio 2019 for .NET

  3. In the Search for templates box, type winforms, and then press Enter.

  4. In the code language dropdown, choose C# or Visual Basic.

  5. In the templates list, select Windows Forms App (.NET) and then click Next.

    Important

    Don't select the Windows Forms App (.NET Framework) template.

    Search for the Windows Forms template in Visual Studio 2019 for .NET

  6. In the Configure your new project window, set the Project name to Names and click Create.

    You can also save your project to a different folder by adjusting the Location setting.

    Configure new Windows Forms project in Visual Studio 2019 for .NET

Once the app is generated, Visual Studio should open the designer pane for the default form, Form1. If the form designer isn't visible, double-click on the form in the Solution Explorer pane to open the designer window.

Important parts of Visual Studio

Support for WinForms in Visual Studio has four important components that you'll interact with as you create an app:

The important components of Visual Studio you should know when creating a Windows Forms project for .NET

  1. Solution Explorer

    All if your project files, code, forms, resources, will appear in this pane.

  2. Properties

    This pane shows property settings you can configure based on the item selected. For example, if you select an item from Solution Explorer, you'll see property settings related to the file. If you select an object in the Designer, you'll see settings for the control or form.

  3. Form Designer

    This is the designer for the form. It's interactive and you can drag-and-drop objects from the Toolbox. By selecting and moving items in the designer, you can visually compose the user interface (UI) for your app.

  4. Toolbox

    The toolbox contains all of the controls you can add to a form. To add a control to the current form, double-click a control or drag-and-drop the control.

Add controls to the form

With the Form1 form designer open, use the Toolbox pane to add the following controls to the form:

  • Label
  • Button
  • Listbox
  • Textbox

You can position and size the controls according to the following settings. Either visually move them to match the screenshot that follows, or click on each control and configure the settings in the Properties pane. You can also click on the form title area to select the form:

Object Setting Value
Form Text Names
Size 268, 180
Label Location 12, 9
Text Names
Listbox Name lstNames
Location 12, 27
Size 120, 94
Textbox Name txtName
Location 138, 26
Size 100, 23
Button Name btnAdd
Location 138, 55
Size 100, 23
Text Add Name

You should have a form in the designer that looks similar to the following:

Visual Studio 2019 designer with the form open for Windows Forms for .NET

Handle events

Now that the form has all of its controls laid out, you need to handle the events of the controls to respond to user input. With the form designer still open, perform the following steps:

  1. Select the button control on the form.

  2. In the Properties pane, click on the events icon to list the events of the button.

  3. Find the Click event and double-click it to generate an event handler.

    This action adds the following code to the the form:

    private void btnAdd_Click(object sender, EventArgs e)
    {
    
    }
    
    Private Sub btnAdd_Click(sender As Object, e As EventArgs) Handles btnAdd.Click
    
    End Sub
    

    The code we'll put in this handler will add the name specified by the txtName textbox control to the lstNames listbox control. However, we want there to be two conditions to adding the name: the name provided must not be blank, and the name must not already exist.

  4. The following code demonstrates adding a name to the lstNames control:

    private void btnAdd_Click(object sender, EventArgs e)
    {
        if (!string.IsNullOrWhiteSpace(txtName.Text) && !lstNames.Items.Contains(txtName.Text))
            lstNames.Items.Add(txtName.Text);
    }
    
    Private Sub btnAdd_Click(sender As Object, e As EventArgs) Handles btnAdd.Click
        If Not String.IsNullOrWhiteSpace(txtName.Text) And Not lstNames.Items.Contains(txtName.Text) Then
            lstNames.Items.Add(txtName.Text)
        End If
    End Sub
    

Run the app

Now that the event has been coded, you can run the app by pressing the F5 key or by selecting Debug > Start Debugging from the menu. The form displays and you can enter a name in the textbox and then add it by clicking the button.

Running a Windows Forms for .NET app.

Next steps