24 game/CSharp: Difference between revisions

Line 4:

You could, for example, use the CodeDOM to dynamically compile an object that contains the expression string.

~~While~~ not necessarily a good coding practice, but certainly a short and simple route, ~~would be~~ to use System.Xml.XPath.XPathNavigator.Evaluate(string xpath) as shown here:

Or, while not necessarily a good coding practice, but certainly a short and simple route, you could use System.Xml.XPath.XPathNavigator.Evaluate(string xpath) as shown here:

public class XPathEval : I24MathParser {

Line 33:

Here is a more verbose, native solution - a lightweight math expression parser for evaluating 24 Game user input:

/// <summary>

/// Lightweight math parser - C# does not have an Evaluate function

/// </summary>

public class MathParser : I24MathParser {

/// <summary>

/// Lightweight math parser - C# does not have an Evaluate function

Line 77:

Line 73:

float Solve(string equation){

float Solve(string equation) {

//carry out order of operations

// bracketed subexpressions - for any operator

Line 96:

Line 92:

Match match = subExpression.Match(equation);

while (match.Success)

while (match.Success) {

⚫

if (match.Groups[1].Length > 0) {

{

⚫

if (match.Groups[1].Length > 0)

{

//recursively solve for subexpressions -- match group 1 excludes outer brackets

subResult = Solve(match.Groups[1].Value);

}

else

else {

{

//no more nested expressions - get final result for this subExpression

subResult = ParseEquation(match.Value);