Stripping out non-numeric characters in string

Question

Hey Im looking to strip out non-numeric characters in a string in ASP.NET C#

So i.e 40,595 p.a.

would end up with 40595

Thanks

Answer 1

Here is the code using Regular Expressions:

string str = "40,595 p.a.";

StringBuilder convert = new StringBuilder();

string pattern = @"\d+";
Regex regex = new Regex(pattern);

MatchCollection matches = regex.Matches(str);

foreach (Match match in matches)
{
convert.Append(match.Groups[0].ToString());
}

int value = Convert.ToInt32(convert.ToString()); 

Answer 2

Feels like a good fit for a regular expression.

var s = "40,595 p.a.";
var stripped = Regex.Replace(s, "[^0-9]", "");

"[^0-9]" can be replaced by @"\D" but I like the readability of [^0-9].

Answer 3

public static string RemoveNonNumeric(string value) => Regex.Replace(value, "[^0-9]", "");

Answer 4

If you're working in VB and ended up here, the ".Where" threw an error for me. Got this from here: https://forums.asp.net/t/1067058.aspx?Trimming+a+string+to+remove+special+non+numeric+characters

Function ParseDigits(ByVal inputString as String) As String
  Dim numberString As String = ""
  If inputString = Nothing Then Return numberString

  For Each c As Char In inputString.ToCharArray()
    If c.IsDigit Then
      numberString &= c
    End If
  Next c

  Return numberString
End Function

Answer 5

There are many ways, but this should do (don't know how it performs with really large strings though):

private static string GetNumbers(string input)
{
    return new string(input.Where(c => char.IsDigit(c)).ToArray());
}