String in VB.net – String Function in VB.net with Example

What is String in VB.net?

The String in VB.net is a sequence of characters collectively referred to as a string.

The text value is saved in a string variable that is created using the String keyword. System.String is the name of the string class, which includes all of the string’s functions.

In VB.net, you can use strings as an array of characters, however, the more common practice is to use the String keyword to declare a string variable.

Declaration and Initialization of String in VB.net

The following are the different ways to Declare and Initialize the String Variable using the String Keyword in VB.net.

'Declaration of the String variable  
Dim str As String  
Dim abc As String  
  
' Initialization of String variable  
Dim str As String = "Welcome to IT SOURCECODE."  
Dim str1 As String = "Hello World!"  
  
' Initialize a null string  
Dim str2 As String = Nothing  
  
' Initialization of an empty string  
Dim name As String = String.Empty   
  
' Creating a String from char  
Dim letter As Char() = {"H", "E",  "L", "L", "O" }  

In the above declaration of string, we have defined the string variable with the string keyword and initialized the string variable with value based on our requirements.

Creating A String Object in VB.net

You can create a String Object in VB.net using one of the following methods:

• By assigning a string literal to a String variable

• By using a String class constructor

• By using the string concatenation operator (+)

• By retrieving a property or calling a method that returns a string

• By calling a formatting method to convert a value or object to its string representation

Let’s create an example to demonstrate the uses of String objects in VB.net.

Module strings
   Sub Main()
      Dim fname, lname, fullname, greetings As String
      fname = "Angel Jude"
      lname = "Suarez"
      fullname = fname + " " + lname
      Console.WriteLine("Full Name: {0}", fullname)

      'by using string constructor
      Dim letters As Char() = {"H", "e", "l", "l", "o"}
      greetings = New String(letters)
      Console.WriteLine("Greetings: {0}", greetings)

      'methods returning String
      Dim sarray() As String = {"Hello", "From", "IT", "SOURCECODE"}
      Dim message As String = String.Join(" ", sarray)
      Console.WriteLine("Message: {0}", message)

      'formatting method to convert a value 
      Dim waiting As DateTime = New DateTime(2022, 06, 25, 12, 00, 1)
      Dim chat As String = String.Format("Message sent at {0:t} on {0:D}", waiting)
      Console.WriteLine("Message: {0}", chat)
      Console.ReadLine()
   End Sub
End Module

When the above code is compiled and executed, it produces the following result:

Full Name: Angel Jude Suarez
Greetings: Hello
Message: Hello From IT SOURCECODE
Message: Message sent at 12:00 PM on Saturday, June 25, 2022

You can test the above example here! ➡ VB.net Online Compiler

Immutable String Object in VB.net

The String Object In VB.net is immutable. It means that once we have created a string object, it cannot be modified during its execution.

If we modify an existing value in a string object through addition and subtraction, it discards the old value of an instance in memory and creates a new instance to hold a new value.

Furthermore, if we want to perform any operation in the String object, we must define an object every time to create a new String object.

So, in that case, the string provides the System.Text.StringBuilder class to modify a string without creating a new object.

Properties of the String Class in VB.net

The String Class in VB.net has the following two properties:

1. Chars

Gets the Char object at a specified position in the current String object.

2. Length

Gets the number of characters in the current String object

Methods of the String Class in VB.net

The String class has numerous methods that help you in working with the String Objects in VB.net.

The following table provides some of the most commonly used methods:

Example Programs of the Methods of the String Class in VB.net

The following example demonstrates some of the methods mentioned above.

Example Program of Comparing String in VB.net:

Module strings
   Sub Main()
      Dim str1, str2 As String
      str1 = "This is test"
      str2 = "This is text"
      
      If (String.Compare(str1, str2) = 0) Then
         Console.WriteLine(str1 + " and " + str2 + " are equal.")
      Else
         Console.WriteLine(str1 + " and " + str2 + " are not equal.")
      End If
      Console.ReadLine()
   End Sub
End Module

When the above code is compiled and executed, it produces the following result:

This is test and This is text are not equal.

You can test the above example here! ➡ VB.net Online Compiler

Example Program of String Contain String in VB.net:

Module strings
   Sub Main()
      Dim str1 As String
      str1 = "This is test"
      
      If (str1.Contains("test")) Then
         Console.WriteLine("The sequence 'test' was found.")
      End If
      Console.ReadLine()
   End Sub
End Module

When the above code is compiled and executed, it produces the following result:

The sequence ‘test’ was found.

You can test the above example here! ➡ VB.net Online Compiler

Example Program of Getting a Substring in VB.net:

Module strings
   Sub Main()
      Dim str As String
      str = "I am a Programmer and I have no Life"
      Console.WriteLine(str)
      
      Dim substr As String = str.Substring(23)
      Console.WriteLine(substr)
      Console.ReadLine()
   End Sub
End Module

When the above code is compiled and executed, it produces the following result:

I am a Programmer and I have no Life
have no Life

You can test the above example here! ➡ VB.net Online Compiler

Example Program of Joining Strings in VB.net:

Module strings
   Sub Main()
      Dim strarray As String() = {
         "I am Angel Jude Suarez",
         "And i am graduated of Bachelor of Science in Information Technology",
         "I am a programmer",
         "And I have no life"
      }
      Dim str As String = String.Join(vbCrLf, strarray)
      Console.WriteLine(str)
      Console.ReadLine()
   End Sub
End Module

When the above code is compiled and executed, it produces the following result:

I am Angel Jude Suarez
And i am graduated of Bachelor of Science in Information Technology
I am a programmer
And I have no life

You can test the above example here! ➡ VB.net Online Compiler

Summary

In this tutorial we discuss the String Function in VB.net with Example, Declaration, and Initialization of String in VB.net, and the Method of String Class in VB.net.

In visual basic, String is a keyword and it is useful to represent a sequential collection of characters that is called a text.

In visual basic, the String keyword is useful to create a string variable to hold the text which is a sequential collection of characters.

PREVIOUS

Loops

NEXT

Date and Time