`Regex.Split`, digits

In VB.NET, it is possible to use Regex.Split to parse the numbers inside a string. We use some metacharacters to split on non-digit characters.

When all non-digit characters are treated as delimiters, we can then loop over the parts and use Integer.Parse to get the integral values from the sequences of digits.

Example

Consider the input string in this example. It contains 3 sequences of digits, and these parts are separated by non-digit parts (unless they occur at the end of string).

Step 1 We print out the input string in the program. As noted, it has 3 digit sequences of 1 or 2 characters each.

Step 2 We use Regex.Split on non-digit (D) characters. The plus means 1 or more chars in a sequence.

Step 3 We loop over the results in the collection (a String array) returned by Regex.Split.

Step 4 If the entry in the array is not Null, we parse it with Integer.Parse and add 1 to it to demonstrate we now have an Integer.

Imports System.Text.RegularExpressions

Module Module1
    Sub Main()

        ' Step 1: declare the input string containing numbers we want to extract.
        Dim input As String = "ABC 4: 3XYZ 10"
        Console.WriteLine($"String: {input}")

        ' Step 2: use Regex.Split on non-digit character sequences.
        Dim numbers = Regex.Split(input, "\D+")

        ' Step 3: loop over all results.
        For Each value As String in numbers
            ' Step 4: parse the number if it is not Null (Nothing).
            If Not String.IsNullOrEmpty(value) 
                Dim numeric = Integer.Parse(value)
                Console.WriteLine("Number: {0} (+1 = {1})", numeric, numeric + 1)
            End If
        Next

    End Sub
End ModuleString: ABC 4: 3XYZ 10
Number: 4 (+1 = 5)
Number: 3 (+1 = 4)
Number: 10 (+1 = 11)

Summary

Instead of a complex parsing routine that iterates over characters, we can use Regex.Split to extract numbers in a string. It is possible to parse the digits into Integers.

Regex.Split, digits

Example

Summary

`Regex.Split`, digits