Question

How to use char to as array index in VB.NET

Answer 1

Imports System
  
Public Class Test
    Public Shared Sub Main()
        Dim count_chars As Integer() = New Integer(255) {}  ' 256 = ASCII table size
		Dim str As String = "bbaddddccce"
  
		For i As Integer = 0 To str.Length - 1
			count_chars(Convert.ToInt32(str(i))) += 1
        Next
  
        For i As Integer = 0 To 256 - 1
            If count_chars(i) > 0 Then
				Console.WriteLine(i & " " & count_chars(i))
            End If
        Next
		
    End Sub
End Class
  
  
  
' run:
'
' 97 1
' 98 2
' 99 3
' 100 4
' 101 1
'
  

 

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Answer 2

Imports System
  
Public Class Test
    Public Shared Sub Main()
        Dim count_chars As Integer() = New Integer(26) {}  ' 256 = ASCII table size
		Dim str As String = "bbaddddccce"
  
		For i As Integer = 0 To str.Length - 1
			count_chars(Convert.ToInt32(str(i)) - Convert.ToByte("a"c)) += 1
        Next
  
        For i As Integer = 0 To 26 - 1
            If count_chars(i) > 0 Then
				Console.WriteLine(i + Convert.ToByte("a"c) & " " & count_chars(i))
            End If
        Next
		
    End Sub
End Class
  
  
  
' run:
'
' 97 1
' 98 2
' 99 3
' 100 4
' 101 1
'

 

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