Learn to use the code editor with Visual Basic

Article
03/10/2023

In this 10-minute introduction to the code editor in Visual Studio, we'll add code to a file to look at some of the ways that Visual Studio makes writing, navigating, and understanding Visual Basic code easier.

Tip

If you haven't already installed Visual Studio, go to the Visual Studio downloads page to install it for free.

This article assumes you're already familiar with Visual Basic. If you aren't, we suggest you look at a tutorial such as Create a simple Visual Basic (VB) console app first.

Tip

To follow along with this article, make sure you have the Visual Basic settings selected for Visual Studio. For information about selecting settings for the integrated development environment (IDE), see Select environment settings.

Create a new code file

Start by creating a new file and adding some code to it.

Open Visual Studio. Press Esc or click Continue without code on the start window to open the development environment.
From the File menu on the menu bar, choose New File.
In the New File dialog box, under the General category, choose Visual Basic Class, and then choose Open.

A new file opens in the editor with the skeleton of a Visual Basic class. (You can already notice that you don't have to create a full Visual Studio project to gain some of the benefits that the code editor offers, such as syntax highlighting. All you need is a code file!)

Open Visual Studio. Press Esc or select Continue without code on the start window to open the development environment.
From the File menu on the menu bar, choose New > File.
In the New File dialog box, under the General category, choose Visual Basic Class, and then choose Open.

A new file opens in the editor with the skeleton of a Visual Basic class. (You can already notice that you don't have to create a full Visual Studio project to gain some of the benefits that the code editor offers, such as syntax highlighting. All you need is a code file!)

Use code snippets

Visual Studio provides useful code snippets that you can use to quickly and easily generate commonly used code blocks. Code snippets are available for different programming languages including Visual Basic, C#, and C++. Let's add the Visual Basic Sub snippet to our file.

Place your cursor above the line that says End Class, and type sub.

A pop-up dialog box appears with information about the Sub keyword and how to insert the Sub code snippet.
Press Tab twice to insert the code snippet.

The outline for the Sub procedure MySub() is added to the file.

The available code snippets vary for different programming languages. You can look at the available code snippets for Visual Basic by choosing Edit > IntelliSense > Insert Snippet (or press Ctrl+K, Ctrl+X). For Visual Basic, code snippets are available for the following categories:

Screenshot showing the Insert Snippet window with a list of category folders that contain Visual Basic code snippets.

There are snippets for determining if a file exists on the computer, writing to a text file, reading a registry value, executing a SQL query, or creating a For Each...Next statement, and many more.

Place your cursor above the line that says End Class, and type sub.

A pop-up dialog box appears with information about the Sub keyword and how to insert the Sub code snippet.
Press Tab twice to insert the code snippet.

The outline for the Sub procedure MySub() is added to the file.

The available code snippets vary for different programming languages. You can look at the available code snippets for Visual Basic by opening the right-click or context menu in the code editor and choosing Snippet > Insert Snippet (or press Ctrl+K, Ctrl+X). For Visual Basic, code snippets are available for the following categories:

Screenshot showing the Insert Snippet window with a list of category folders that contain Visual Basic code snippets.

Comment out code

The toolbar, which is the row of buttons under the menu bar in Visual Studio, can help make you more productive as you code. For example, you can toggle IntelliSense completion mode, increase or decrease a line indent, or comment out code that you don't want to compile. (IntelliSense is a coding aid that displays a list of matching methods, amongst other things.) In this section, we'll comment out some code.

Screenshot showing the toolbar in Visual Studio which includes buttons for adding or removing code comments.

Paste the following code into the MySub() procedure body.

' _words is a string array that we'll sort alphabetically
Dim _words = New String() {
"the",
"quick",
"brown",
"fox",
"jumps"
}

Dim morewords = New String() {
"over",
"the",
"lazy",
"dog"
}

Dim query = From word In _words
            Order By word.Length
            Select word

We're not using the morewords array, but we may use it later so we don't want to completely delete it. Instead, let's comment out those lines. Select the entire definition of morewords to the closing curly brace, and then choose the Comment out the selected lines button on the toolbar. If you prefer to use the keyboard, press Ctrl+K, Ctrl+C.

The Visual Basic comment character ' is added to the beginning of each selected line to comment out the code.

Screenshot showing the toolbar in Visual Studio which includes buttons for adding or removing code comments.

Paste the following code into the MySub() procedure body.

' _words is a string array that we'll sort alphabetically
Dim _words = New String() {
"the",
"quick",
"brown",
"fox",
"jumps"
}

Dim morewords = New String() {
"over",
"the",
"lazy",
"dog"
}

Dim query = From word In _words
            Order By word.Length
            Select word

We're not using the morewords array, but we may use it later so we don't want to completely delete it. Instead, let's comment out those lines. Select the entire definition of morewords to the closing curly brace, and then choose the Comment out the selected lines button on the toolbar. If you prefer to use the keyboard, press Ctrl+K, Ctrl+C.

The Visual Basic comment character ' is added to the beginning of each selected line to comment out the code.

Collapse code blocks

You can collapse sections of code to focus just on the parts that are of interest to you. To practice, let's collapse the _words array to one line of code. Choose the small gray box with the minus sign inside it in the margin of the line that says Dim _words = New String() {. Or, if you're a keyboard user, place the cursor anywhere in the array definition and press Ctrl+M, Ctrl+M.

The code block collapses to just the first line, followed by an ellipsis (...). To expand the code block again, click the same gray box that now has a plus sign in it, or press Ctrl+M, Ctrl+M again. This feature is called Outlining and is especially useful when you're collapsing long methods or entire classes.

The code block collapses to just the first line, followed by an ellipsis (...). To expand the code block again, choose the same gray box that now has a plus sign in it, or press Ctrl+M, Ctrl+M again. This feature is called Outlining and is especially useful when you're collapsing long methods or entire classes.

View symbol definitions

The Visual Studio editor makes it easy to inspect the definition of a type, method, etc. One way is to navigate to the file that contains the definition, for example by choosing Go to Definition anywhere the symbol is referenced. An even quicker way that doesn't move your focus away from the file you're working in is to use Peek Definition. Let's peek at the definition of the String type.

Right-click on the word String and choose Peek Definition from the content menu. Or, press Alt+F12.

A pop-up window appears with the definition of the String class. You can scroll within the pop-up window, or even peek at the definition of another type from the peeked code.
Close the peeked definition window by choosing the small box with an "x" at the top right of the pop-up window.

The Visual Studio editor makes it easy to inspect the definition of a type or class member. One way is to navigate to the file that contains the definition, for example by choosing Go to Definition anywhere the symbol is referenced. An even quicker way that doesn't move your focus away from the file you're working in is to use Peek Definition. Let's peek at the definition of the String type.

Right-click on the word String and choose Peek Definition from the content menu. Or, press Alt+F12.

A pop-up window appears with the definition of the String class. You can scroll within the pop-up window, or even peek at the definition of another type from the peeked code.
Close the peek definition window by choosing the small box with an "x" at the top right of the pop-up window.

Use IntelliSense to complete words

IntelliSense is an invaluable resource when you're coding. It can show you information about available members of a type, or parameter details for different overloads of a method. You can also use IntelliSense to complete a word after you type enough characters to disambiguate it. Let's add a line of code to print out the ordered strings to the console window, which is the standard place for output from the program to go.

Below the query variable, start typing the following code:
```
For Each str In qu
```
You see IntelliSense show you Quick Info about the query symbol.
To insert the rest of the word query by using IntelliSense's word completion functionality, press Tab.
Finish off the code block to look like the following code.
```
For Each str In query
    Console.WriteLine(str)
Next
```

Below the query variable, start typing the following code:
```
For Each str In qu
```
You see IntelliSense show you Quick Info about the query symbol.
To insert the rest of the word query by using IntelliSense's word completion functionality, press Tab.
Finish off the code block to look like the following code.
```
For Each str In query
    Console.WriteLine(str)
Next
```

Refactor a name

Nobody gets code right the first time, and one of the things you might have to change is the name of a variable or method. Let's try out Visual Studio's refactor functionality to rename the _words variable to words.

Place your cursor over the definition of the _words variable and choose Rename from the right-click or context menu.

A pop-up Rename dialog box appears at the top right of the editor.
With the variable _words still selected, type in the desired name of words. Notice that the reference to words in the query is also automatically renamed. Before you press Enter or click Apply, select the Include comments checkbox in the Rename pop-up box.
Press Enter or click Apply.

Both occurrences of words are renamed, as well as the reference to words in the code comment.

Place your cursor over the definition of the _words variable and choose Rename from the right-click or context menu.

A pop-up Rename dialog box appears at the top right of the editor.
With the variable _words still selected, type in the desired name of words. Notice that the reference to words in the query is also automatically renamed. Before you press Enter or Apply, select the Include comments checkbox in the Rename pop-up box.
Press Enter or choose Apply.

Both occurrences of words are renamed, as well as the reference to words in the code comment.

Next steps

Learn about projects and solutions