public virtual string replaceVariables(string expression)
{
int openIndex = expression.IndexOf(EvaluationConstants.OPEN_VARIABLE, StringComparison.Ordinal);
if (openIndex < 0)
{
return(expression);
}
string replacedExpression = expression;
while (openIndex >= 0)
{
int closedIndex = -1;
if (openIndex >= 0)
{
closedIndex = replacedExpression.IndexOf(EvaluationConstants.CLOSED_VARIABLE, openIndex + 1, StringComparison.Ordinal);
if (closedIndex > openIndex)
{
string variableName = StringHelperClass.SubstringSpecial(replacedExpression, openIndex + EvaluationConstants.OPEN_VARIABLE.Length, closedIndex);
// Validate that the variable name is valid.
try
{
isValidName(variableName);
}
catch (System.ArgumentException iae)
{
throw new EvaluationException("Invalid variable name of \"" + variableName + "\".", iae);
}
string variableValue = getVariableValue(variableName);
string variableString = EvaluationConstants.OPEN_VARIABLE + variableName + EvaluationConstants.CLOSED_VARIABLE;
replacedExpression = EvaluationHelper.replaceAll(replacedExpression, variableString, variableValue);
}
else
{
break;
}
}
openIndex = replacedExpression.IndexOf(EvaluationConstants.OPEN_VARIABLE, StringComparison.Ordinal);
}
// If an open brace is left over, then a variable could not be replaced.
int openBraceIndex = replacedExpression.IndexOf(EvaluationConstants.OPEN_VARIABLE, StringComparison.Ordinal);
if (openBraceIndex > -1)
{
throw new EvaluationException("A variable has not been closed (index=" + openBraceIndex + ").");
}
return(replacedExpression);
}