/// <summary>
/// Strips the special attributes specified at the location of start. Special attributes are a php markdown extension
/// and specified between {}. Attributes are separated with spaces. It recognizes the following attributes:
/// id, which start with a '#'. Only the first one is used
/// css classes, which start with a'.'. All specified are used
/// name=value pairs, which will end up as attributes on the element.
/// </summary>
/// <param name="str">The string we're scanning.</param>
/// <param name="start">The start (current) position.</param>
/// <param name="end">The end position. Is only valid if returned list contains at least one value.</param>
/// <returns>list of special attributes found, or null if none found or error in string format.</returns>
public static List <string> StripSpecialAttributes(string str, int start, out int end)
{
end = start;
var scanner = new StringScanner(str, start);
if (!scanner.DoesMatch('{'))
{
// not a start of a special attribute block
return(null);
}
// first find the end of the block,
scanner.SkipForward(1);
var startOfAttributes = scanner.Position;
// first find the next EOL, as the closing } has to be on this line.
scanner.SkipToEol();
var nextEolPos = scanner.Position;
scanner.Position = startOfAttributes;
scanner.Mark();
if (!scanner.Find('}') || scanner.Position >= nextEolPos)
{
// not enclosed properly.
return(null);
}
var attributesString = scanner.Extract();
if (string.IsNullOrWhiteSpace(attributesString))
{
return(null);
}
// Position is on enclosing '}' (due to the Find('}'), so we have to skip 1 character
end = scanner.Position + 1;
return(attributesString.Split(' ').Where(s => !string.IsNullOrWhiteSpace(s)).ToList());
}
