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StringCollection.Add Method

Adds a string to the end of the StringCollection.

Namespace:  System.Collections.Specialized
Assembly:  System (in System.dll)

'Declaration
Public Function Add ( _
	value As String _
) As Integer

Parameters

value
Type: System.String

The string to add to the end of the StringCollection. The value can be Nothing.

Return Value

Type: System.Int32
The zero-based index at which the new element is inserted.

StringCollection accepts Nothing as a valid value and allows duplicate elements.

If Count is less than the capacity, this method is an O(1) operation. If the capacity needs to be increased to accommodate the new element, this method becomes an O(n) operation, where n is Count.

The following code example adds new elements to the StringCollection.

Imports System
Imports System.Collections
Imports System.Collections.Specialized

Public Class SamplesStringCollection   

   Public Shared Sub Main()

      ' Creates and initializes a new StringCollection. 
      Dim myCol As New StringCollection()

      Console.WriteLine("Initial contents of the StringCollection:")
      PrintValues(myCol)

      ' Adds a range of elements from an array to the end of the StringCollection. 
      Dim myArr() As [String] = {"RED", "orange", "yellow", "RED", "green", "blue", "RED", "indigo", "violet", "RED"}
      myCol.AddRange(myArr)

      Console.WriteLine("After adding a range of elements:")
      PrintValues(myCol)

      ' Adds one element to the end of the StringCollection and inserts another at index 3.
      myCol.Add("* white")
      myCol.Insert(3, "* gray")

      Console.WriteLine("After adding ""* white"" to the end and inserting ""* gray"" at index 3:")
      PrintValues(myCol)

   End Sub 'Main

   Public Shared Sub PrintValues(myCol As IEnumerable)
      Dim obj As [Object]
      For Each obj In  myCol
         Console.WriteLine("   {0}", obj)
      Next obj
      Console.WriteLine()
   End Sub 'PrintValues

End Class 'SamplesStringCollection 


'This code produces the following output. 

'Initial contents of the StringCollection: 

'After adding a range of elements: 
'   RED 
'   orange 
'   yellow 
'   RED 
'   green 
'   blue 
'   RED 
'   indigo 
'   violet 
'   RED 

'After adding "* white" to the end and inserting "* gray" at index 3: 
'   RED 
'   orange 
'   yellow 
'   * gray 
'   RED 
'   green 
'   blue 
'   RED 
'   indigo 
'   violet 
'   RED 
'   * white 
'

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
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