public Boolean IsValid(String strExp, ref String strRetMsg)
{
Boolean bRet = true;
calcExprLexer lex = new calcExprLexer(new AntlrInputStream("=" + strExp));
CommonTokenStream tokens = new CommonTokenStream(lex);
calcExprParser parser = new calcExprParser(tokens);
IParseTree tree = null;
try
{
tree = parser.parse();
if (parser.NumberOfSyntaxErrors > 0)
{
bRet = false;
strRetMsg = "公式:" + "'" + strExp + "'有语法错误，请查看帮助中公式的语法要求";
}
}
catch (RecognitionException ex)
{
bRet = false;
strRetMsg = "位置：" + parser.GetErrorHeader(ex) + ":公式:" + "'" + strExp + "'有语法错误，请查看帮助中公式的语法要求";
}
return(bRet);
}
private String Computing(String strExp, Hashtable hashAllVars, ref Hashtable refVarsHash, ref String strMsg)
{
calcExprLexer lex = new calcExprLexer(new AntlrInputStream("=" + strExp));
CommonTokenStream tokens = new CommonTokenStream(lex);
calcExprParser parser = new calcExprParser(tokens);
// ParseTreeWalker walker = new ParseTreeWalker();
// calcExprBaseListener listener = new calcExprBaseListener();
EvalExprVisitor visitor = new EvalExprVisitor();
visitor.SetRefVarsHash(refVarsHash);
visitor.SetVarHash(hashAllVars);//m_varsHash);
IParseTree tree = null;
EvalResult ret = null;
try
{
tree = parser.parse();
if (tree != null)
{
ret = visitor.Visit(tree);
}
}
catch (RecognitionException ex)
{
strMsg = ex.Message;
System.Console.Error.WriteLine(ex.StackTrace);
return(null);
}
if (ret == null)
{
return(null);
}
if (ret.bInvalid)
{
return(ret.strExceptionMsg);
}
return(ret.Value1.ToString());
}