Example #1
0
 private string TranslateToNETRegex(VBALikeParser.LikePatternStringContext likePattern)
 {
     StringBuilder regexStr = new StringBuilder();
     foreach (var element in likePattern.likePatternElement())
     {
         if (element.likePatternChar() != null)
         {
             regexStr.Append(element.likePatternChar().GetText());
         }
         else if (element.QUESTIONMARK() != null)
         {
             regexStr.Append(".");
         }
         else if (element.HASH() != null)
         {
             regexStr.Append(@"\d");
         }
         else if (element.STAR() != null)
         {
             regexStr.Append(@".*?");
         }
         else
         {
             var charlist = element.likePatternCharlist().GetText();
             if (charlist.StartsWith("[!"))
             {
                 charlist = "[^" + charlist.Substring(2);
             }
             regexStr.Append(charlist);
         }
     }
     // Full string match, e.g. "abcd" should NOT match "a.c"
     var regex = "^" + regexStr.ToString() + "$";
     return regex;
 }
Example #2
0
 public override IValue Evaluate()
 {
     var expr = _expression.Evaluate();
     var pattern = _pattern.Evaluate();
     if (expr == null || pattern == null)
     {
         return null;
     }
     var exprStr = expr.AsString;
     var patternStr = pattern.AsString;
     var stream = new AntlrInputStream(patternStr);
     var lexer = new VBALikeLexer(stream);
     var tokens = new CommonTokenStream(lexer);
     var parser = new VBALikeParser(tokens);
     var likePattern = parser.likePatternString();
     var regex = TranslateToNETRegex(likePattern);
     return new BoolValue(Regex.IsMatch(exprStr, regex));
 }
        /// <summary>
        /// Parses the given like pattern.
        /// </summary>
        /// <param name="likePattern">The like pattern of the like operation (e.g. in "a Like b" the b)</param>
        /// <returns>The root of the parse tree.</returns>
        public VBALikeParser.LikePatternStringContext Parse(string likePattern)
        {
            var stream = new AntlrInputStream(likePattern);
            var lexer  = new VBALikeLexer(stream);
            var tokens = new CommonTokenStream(lexer);
            var parser = new VBALikeParser(tokens);

            //parser.AddErrorListener(new ExceptionErrorListener());
            VBALikeParser.CompilationUnitContext tree;
            try
            {
                parser.Interpreter.PredictionMode = PredictionMode.Sll;
                tree = parser.compilationUnit();
            }
            catch (Exception ex)
            {
                Logger.Warn(ex, "SLL mode failed for {0}. Retrying using LL.", likePattern);
                tokens.Reset();
                parser.Reset();
                parser.Interpreter.PredictionMode = PredictionMode.Ll;
                tree = parser.compilationUnit();
            }
            return(tree.likePatternString());
        }