Working with Data Structures in VB.NET NameValueCollection

In VB.NET, a NameValueCollection is a special type of collection that stores key-value pairs. Each key is unique and gets associated with a value. In this page, we will discuss how to work with NameValueCollection in VB.NET.

Syntax

Here is the syntax for creating a NameValueCollection:

Dim obj as New NameValueCollection

Here is the syntax to add a key-value pair to the NameValueCollection:

obj.Add(Key,value)

You can also use the indexer to add or update a key-value pair:

obj(Key) = value

Here is the syntax to access a value by key:

obj(Key)

Example

Here's an example of how to create, add, and access values in a NameValueCollection:

Dim obj As New NameValueCollection()

'Adding values to collection
obj.Add("Name", "John")
obj.Add("Age", "30")
obj.Add("Location", "California")
obj.Add("Skills", "VB.NET")

'Accessing values from the collection
Dim name As String = obj("Name")
Dim age As Integer = Integer.Parse(obj("Age"))
Dim location As String = obj("Location")
Dim skills As String() = obj.GetValues("Skills")

'Printing the values on the console
Console.WriteLine("Name: " & name)
Console.WriteLine("Age: " & age)
Console.WriteLine("Location: " & location)
Console.WriteLine("Skills: ")
For Each skill In skills
    Console.WriteLine(skill)
Next

Output

The output of this code will be:

Name: John
Age: 30
Location: California
Skills:
VB.NET

Explanation

In this example, we create a new NameValueCollection and add key-value pairs using the Add method. We then retrieve the values using the Item property, which accepts the key as the index. We also use the GetValues method to retrieve all the values associated with a particular key. Finally, we print the values to the console.

Use

NameValueCollection is useful when you want to store and access key-value pairs. It is commonly used when working with HTTP requests and responses, as well as configuration files.

Important Points

• The NameValueCollection stores key-value pairs.
• Each key in NameValueCollection is unique.
• You can access a value in NameValueCollection by using the Item property or the GetValues method.

Summary

In this page, we discussed how to work with NameValueCollection in VB.NET. We covered the syntax, example, output, explanation, use, and important points of NameValueCollection. By using NameValueCollection, you can easily store and access key-value pairs in your VB.NET applications.