help with converter

well im basicly a noob too visual basic .NET and i need some help with this i wanted to try to make a text converter
this is what i have so far

Code:

---

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

  textBox2.Text = ConvertMe(textBox1.Text)

End Sub

Function ConvertMe(ByVal textData as String) as String

  Dim tempChar as String ' holds a character to compare to
  Dim textConversion as String 'holds the converted text
  textConversion = "" ' initialize empty string VB may already do this i don't know.

  tempChar = textConversion.SubString(0,1) ' get the first char in the string
   
  if tempChar = "a" Then
      textConversion+= "4"
  End If
   
    return textConversion
End Function

---

but i cant seem to get it to work, ne help would be very nice

Convert a string to what type ?

Is this what you want ?

VB Code:

Private Function Changeto(ByVal str As String) As String
        Dim ChangedStr As String = Nothing
        ChangedStr = Replace(str, "e", "3", 1, 3, CompareMethod.Text)
        MsgBox(ChangedStr)
    End Function
 
'Usage
Changeto("phear")

yea ill try to get that to work