This blog defines IndexOf() and LastIndexOf()
methods.
Indexof() method
To find the index of the first occurrence of
the specified substring. Use the ideal IndexOf String Function for this, which
is available in the .NET Framework's base class library.
IndexOf(String str) As Integer
Here,
str - The parameter string to check its occurrences
LastIndexOf() method
To find index position of the last occurrence
of a specified String within this instance.
For example
Module
Module1
Sub Main()
Dim myStrings As
String() = {"hello",
"be", "or",
"hello", "to",
"be"}
Dim myString As
String = [String].Join(".",
myStrings)
Dim index As
Integer = myString.IndexOf("he")
Console.WriteLine("""be""
first occurs at index " & index & " of
myString")
index =
myString.LastIndexOf("lo")
Console.WriteLine("""be""
last occurs at index " & index & " of
myString")
index =
myString.IndexOf("b"c)
Console.WriteLine("'b'
first occurs at index " & index & " of
myString")
index =
myString.LastIndexOf("b"c)
Console.WriteLine("'b'
last occurs at index " & index & " of
myString")
End Sub
End
Module