The following function returns the part of the passed string that matches the regular expression provided. You can use this function to get the necessary data from fields in a form, etc.
The function takes three parameters: the string to validate, the regular expression, and the grouping pattern that you need. If the pattern is not found, the function returns an empty string, as shown below:
Protected Shared Function GetWithRegEx(ByVal inputStr As String,
ByVal regexStr As String, ByVal groupStr As String) As String
Dim outStr As String
Dim re As New Regex(regexStr)
If re.IsMatch(inputStr) Then
outStr = re.Replace(inputStr, groupStr)
outStr = Nothing
Here's an example of how to use it. The following code searches for 10 numbers in the input string, and if it finds them, it returns only the numbers, so that you can save them in a file or database, etc.
ublic Shared Function GetPhone(ByVal inputStr As String) As Object
Dim phoneStr As Object
phoneStr = GetWithRegEx(inputStr,
If phoneStr = Nothing Then
phoneStr = DBNull.Value