VB.Net Tutorial/Data Type/String and Byte Char Array

Convert String to Char using System.Convert.ToChar

<source lang="vbnet">Imports System.Collections public class ConvertToChar

  public Shared Sub Main
              Dim c As Char
              c = System.Convert.ToChar("A")
       Console.WriteLine(c)
  End Sub

End class</source>

A

Loop through characters in string and display reversed

<source lang="vbnet">Module Tester

  Sub Main()
     Dim string1 As String
     Dim characterArray As Char()
     Dim i As Integer
     Dim quotes As Char = ChrW(34)
     string1 = "hello there"
     characterArray = New Char(5) {}
     For i = string1.Length - 1 To 0 Step -1
        Console.WriteLine(string1.Chars(i))
     Next
  End Sub " Main

End Module</source>

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Reorder chars in a string

<source lang="vbnet">Public Class Tester

   Public Shared Sub Main
       Dim counter As Integer
       Dim position As Integer
       Dim holdChar As Char
       Dim jumbleMethod As New Random
       Dim quote As String = "abcedfg"
       Dim chars() As Char = CType(quote, Char())
       For counter = 0 To chars.Length - 1
           position = jumbleMethod.Next Mod chars.Length
           holdChar = chars(counter)
           chars(counter) = chars(position)
           chars(position) = holdChar
       Next counter
       Dim result As String = New String(chars)
       Console.WriteLine(result)
   End Sub

End Class</source>

cfabdge

String and char array

<source lang="vbnet">Public Class Tester

   Public Shared Sub Main
       Dim quote As String = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
       Dim charArray() As Char = CType(quote, Char())
       charArray(6) = "!"c
       Dim result As String = New String(charArray)
       Console.WriteLine(result)
   End Sub

End Class</source>

aaaaaa!aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Strings And Byte Arrays

<source lang="vbnet">Public Class Tester

   Public Shared Sub Main
       Dim quote As String = "AAAAAasdfasdfasdfasdfasdfasdfasdfadsfasdfadsfads"
       Dim bytes() As Byte
       " ----- Assumed to be all ASCII character.
       bytes = System.Text.Encoding.UTF8.GetBytes(quote)
       bytes(46) = 33    " ASCII exclamation point
       Console.WriteLine(System.Text.Encoding.UTF8.GetString(bytes))
       " ----- Works with all character sets.
       bytes = System.Text.Encoding.Unicode.GetBytes(quote)
       bytes(92) = 63    " ASCII question mark
       bytes(93) = 0
       Console.WriteLine(System.Text.Encoding.Unicode.GetString(bytes))
   End Sub

End Class</source>

AAAAAasdfasdfasdfasdfasdfasdfasdfadsfasdfadsfa!s
AAAAAasdfasdfasdfasdfasdfasdfasdfadsfasdfadsfa?s

ToCharArray methods

<source lang="vbnet">Imports System.Text Module Tester

  Sub Main()
     Dim string1 As String = "hello"
     Dim i As Integer
     Dim charArray() As Char = string1.ToCharArray()

     " display contents of charArray
     For i = 0 To charArray.Length - 1
        Console.WriteLine(charArray(i))
     Next
  End Sub " Main

End Module</source>

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Use IndexOf to locate a character in a string

<source lang="vbnet">Module Tester

  Sub Main()
     Dim letters As String = "abcdefghijklmabcdefghijklm"
     Dim searchLetters As Char() = New Char() {"c"c, "a"c, "$"c}
     
     Console.WriteLine(letters.IndexOf("c"c))
     Console.WriteLine(letters.IndexOf("a"c, 1))
     Console.WriteLine(letters.IndexOf("$"c, 3, 5))
  End Sub " Main

End Module " modIndexMethods</source>

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Use LastIndexOf to find a character in a string

<source lang="vbnet">Module Tester

  Sub Main()
     Dim letters As String = "abcdefghijklmabcdefghijklm"
     Dim searchLetters As Char() = New Char() {"c"c, "a"c, "$"c}
     
     Console.WriteLine(letters.LastIndexOf("c"c))
     Console.WriteLine(letters.LastIndexOf("a"c, 25))
     Console.WriteLine(letters.LastIndexOf("$"c, 15, 5))
  End Sub 

End Module</source>

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