/// <summary>
/// Parses the the specified expression into a
/// <see cref="BooleanExpression"/>.
/// </summary>
/// <param name="expression">An expression.</param>
/// <returns>A <see cref="BooleanExpression"/>
/// object that is the root of the parse tree.</returns>
public BooleanExpression Parse(string expression)
{
this.lexer = new LexicalAnalyzer(expression);
this.MoveNext();
BooleanExpression c = this.ParseOrOperator();
this.AssertTokenType(TokenType.EndOfFile);
return c;
}
/// <summary>
/// Parses the the specified expression into a
/// <see cref="BooleanExpression"/>.
/// </summary>
/// <param name="expression">An expression.</param>
/// <returns>A <see cref="BooleanExpression"/>
/// object that is the root of the parse tree.</returns>
public BooleanExpression Parse(string expression)
{
this.lexer = new LexicalAnalyzer(expression);
this.MoveNext();
BooleanExpression c = this.ParseOrOperator();
this.AssertTokenType(TokenType.EndOfFile);
return(c);
}
private void HighlightTokens()
{
this.SelectionStart = 0;
this.SelectionLength = this.Text.Length;
this.SelectionUnderlineColor = UnderlineColor.None;
this.SelectionUnderlineStyle = UnderlineStyle.None;
LexicalAnalyzer lexer = new LexicalAnalyzer(this.Text);
TokenType lastToken = TokenType.Any;
for (TokenType tokenType = lexer.MoveNext(); tokenType != TokenType.EndOfFile; tokenType = lexer.MoveNext())
{
this.SelectionStart = lexer.CurrentMatch.Index;
this.SelectionLength = lexer.CurrentMatch.Length;
switch (tokenType)
{
case TokenType.And:
case TokenType.Or:
case TokenType.Not:
this.SelectionColor = Color.Blue;
break;
case TokenType.Identity:
case TokenType.Role:
this.SelectionColor = Color.Navy;
break;
case TokenType.Word:
case TokenType.QuotedString:
if (lastToken == TokenType.Identity || lastToken == TokenType.Role)
{
this.SelectionColor = Color.Navy;
}
else
{
this.SelectionColor = Color.Black;
}
break;
default:
this.SelectionColor = Color.Black;
break;
}
lastToken = tokenType;
}
}
