Validates the syntax of this OrderByList.
            
| C# | Visual Basic | Visual C++ | 
public virtual void ValidateSyntax()
Public Overridable Sub ValidateSyntax
public: virtual void ValidateSyntax ()
            An OrderByList is valid if it is 
            non-empty (must contain at least one OrderBy 
            element) and all its OrderBy elements 
            are themselves valid.
            
| Exception | Condition | 
|---|---|
| SyntaxException | 
            If the  OrderByList does not contain at least
            one OrderBy.
             |