How do I use a regular expression to match strings that don't start with an empty space?

I want a regular expression 开发者_运维百科that checks that a string doesn't start with an empty space.

I want to do something like this:

Is the following ValidationExpression right for it?

string ValidationExpression = @"/^[^ ]/";

if (!String.IsNullOrEmpty(GroupName) && !Regex.IsMatch(GroupName, ValidationExpression))
{    
}

How about "^\S" This will make sure that the first character is not a whitespace character.

You can also use:

   if(GroupName.StartsWith(string.Empty)); // where GroupName == any string

Regex rx = new Regex(@"^\s+");

You can check with

  Match m1 = rx.Match("   ");  //m1.Success should be true
  Match m2 = rx.Match("qwerty   ");  //m2.Success should be false

Something like this, maybe :

/^[^ ]/

And, for a couple of notes about that :

• The first ^ means "string starts with"
• The [^ ] means "one character that is not a space"
• And the // are regex delimiter -- not sure if they are required in C#, though.