Split String By Pascal Case.cs

public static string SplitStringByCase(this string str)
{
    if (!string.IsNullOrWhiteSpace(str))
    {
        return Regex.Replace(str, "[A-Z0-9]((?![A-Z0-9].)|(?<![A-Z0-9].))", " $0").Trim();
    }
    else
    {
        return "";
    }
}
 /* 
  Ignores groupings of capital letters and numbers
  (?! is negative look-ahead, and (?<! is negative look-behind...
  so this checks to see if either 
  * next character is not a capital or number 
  or 
  * previous character is not a capital or number
  So, if either the next or the previous character is not a capital and not a number, add a space
  
  EXAMPLES:
  SimpleText => "Simple Text"
  One => "One"
  ABCCorporation => "ABC Corporation"
  IAmNotHere => "I Am Not Here"
  MixedStringBBCStructure => "Mixed String BBC Structure"
  Numbers123CauseManyProblemsIKnow => "Numbers 123 Cause Many Problems I Know"
  
  Practice online at: https://regex101.com/
  
*/