Android Question String function! replace group of chars with a single char

Dim strVar As String="My name is Beja from the state of ********* located in the USA"
strVar=strVar.Replace(strVar.SubString2(strVar.IndexOf("*"),strVar.LastIndexOf("*")+1),"*")
Msgbox(strVar,"")  'displays only one star in sentence

Msgbox(ReplaceManyWithOne("My name is Beja from the state of ********* located in the USA","*"),"")  'displays only 1 star in sentence

Sub ReplaceManyWithOne(strVar As String,MyChar As String) As String
    Return strVar.Replace(strVar.SubString2(strVar.IndexOf(MyChar),strVar.LastIndexOf(MyChar)+1),MyChar)
End Sub

Dim strVar As String="*I am ** and I am from ****, have a nice day*"
Dim OldLength As Int = 0
Do While OldLength <> strVar.Length
   OldLength = strVar.Length
   strVar = strVar.Replace("**","*")
Loop

Dim Txt As String = "***Regex *** is******** **your * * * friend**** ******** ** ***"
Dim Pattern As String = "([*])\1+"
Dim Replacement As String = "*"

Dim Matcher1 As Matcher
Matcher1 = Regex.Matcher(Pattern, Txt)

Dim r As Reflector
r.Target = Matcher1
Label1.Text = r.RunMethod2("replaceAll", Replacement, "java.lang.String")

    Dim TestStr As String = "** Test *** Removal ***** ***"
    Log(RemoveDuplicates("*",TestStr))

Sub RemoveDuplicates(ThisChar As String, TargetString As String) As String

    Do While TargetString.Contains(ThisChar & ThisChar)
        TargetString = TargetString.Replace(ThisChar & ThisChar,ThisChar)
    Loop
    Return TargetString
End Sub