check does string contain more than one white space [duplicate]

Answer 1

This is probably a fast implementation:

public static bool HasConsecutiveSpaces(string text)
{
    bool inSpace = false;

    foreach (char ch in text)
    {
        if (ch == ' ')
        {
            if (inSpace)
            {
                return true;
            }

            inSpace = true;
        }
        else
        {
            inSpace = false;
        }
    }

    return false;
}

But if you don't really need to worry about speed, just use the regexp solution given in a previous answer.

Answer 2

I assume you're looking for multiple consecutive whitespaces.
I'd use System.Text.RegularExpressions.Regex for that.

Regex regex = new Regex(@"\s{2,}"); // matches at least 2 whitespaces
if (regex.IsMatch(inputString))
    // do something