Check if a string start with any character in a list

Question

I want to check whether a string starts with any character in a list. My current implementation in C# is as follows:

char[] columnChars = new char[] { 'A', 'B', 'C', 'D', 'E' };
private bool startWithColumn(string toCheck)
{
   for(int i=0; i<columnChars.Length; i++)   
     if (toCheck.StartsWith(columnChars[i]+""))
     {
       return true;
     }

   return false;
}

I would like to know if any solution is better?

Answer 1

Turn the check around and see if the first character is in the allowable set.

 char[] columnChars = new char[] { 'A', 'B', 'C', 'D', 'E' };
 private bool startWithColumn(string toCheck)
 {
     return toCheck != null
                && toCheck.Length > 0
                && columnChars.Any( c => c == toCheck[0] );
 }

Answer 2

You can get the first character out of a string easily enough:

char c = toCheck[0];

And then check whether it's in the array:

return columnChars.Contains(c);