I've been using text.indexof() to see if a string is located inside another string, however is it it possible to do a case sensitive/insensitive search option? I've been looking around Google and not having much luck with it.
A huge bonus would be if it could count the number of occurrences inside the string!
There are several overloads of IndexOf that take a StringComparison parameter, allowing you to specify the various culture and case-sensitivity options.
For example:
Dim idx As Integer = haystack.IndexOf(needle, StringComparison.OrdinalIgnoreCase) As for counting occurrences, there's nothing built-in, but it's pretty straightforward to do it yourself:
Dim haystack As String = "The quick brown fox jumps over the lazy dog" Dim needle As String = "th" Dim comparison As StringComparison = StringComparison.OrdinalIgnoreCase Dim count As Integer = CountOccurrences(haystack, needle, comparison) ' ... Function CountOccurrences(ByVal haystack As String, ByVal needle As String, _ ByVal comparison As StringComparison) As Integer Dim count As Integer = 0 Dim index As Integer = haystack.IndexOf(needle, comparison) While index >= 0 count += 1 index = haystack.IndexOf(needle, index + needle.Length, comparison) End While Return count End Function 
Replace that take a StringComparison argument. I have a C# extension method to do this and I can paste that in if you like. (I'm not very fluent in VB myself and don't have time to translate it at the moment. Sorry.)