To check whether the string value has numeric value or not in C#

Question

I am having an string like this

string str = \"dfdsfdsf8fdfdfd9dfdfd4\"

I need to check whether the string contains number by looping through the array.

Answer 1

If you are looking for an integer value you could use int.TryParse:

int result;
if (int.TryParse("123", out result))
{
    Debug.WriteLine("Valid integer: " + result);
}
else
{
    Debug.WriteLine("Not a valid integer");
}

For checking a decimal number, replace int.TryParse with Decimal.TryParse. Check out this blog post and comments "Why you should use TryParse() in C#" for details.

If you need decimal numbers, you could alternatively use this regular expression:

return System.Text.RegularExpressions.Regex.IsMatch(
   TextValue, @"^-?\d+([\.]{1}\d*)?$");

And finally another alternative (if you are not religiously against VB.NET), you could use the method in the Microsoft.VisualBasic namespace:

Microsoft.VisualBasic.Information.IsNumeric("abc");