RuleEngine

Purpose

This simple rule engine is a .NET Standard library 2.0, which uses Microsoft's DLR DynamicExpressionParser in the background. The goal was to make a simple engine which is easy to use and compatible with many projects.

Use

Instantiating the kernel

The IKernel interface is implemented with Kerner in order to support Inverson Of Control.

IKernelruleEngine=newKernel();

Role of the IRule

The engine is designed to use any object as a rule which implements IRule interface in order to make it easy to use with an ORM.

publicinterfaceIRule{stringKey{get;set;}stringExpression{get;set;}}

//...voidAddRule(IRulerule);//...

Simple Validation

String expressions can be simply against the object passed to the engine.
Creating a fact:

varfact=newPerson{Age=37,Income=45000,NumberOfChildren=3};

Validating the fact:

varresult=ruleEngine.Validate(fact,"(f.Age > 3 && f.Income > 100000) || f.NumberOfChildren > 5");// result = false

Validate All

More than one expreession can be added to the engine

varrules=newList<Rule>{newRule{Key="1",Expression="(f.Age > 3 && f.Income < 50000) || f.NumberOfChildren > 2"},newRule{Key="2",Expression="(f.Age > 3 && f.Income > 100000) || f.NumberOfChildren > 5"}};ruleEngine.AddRules(rules);// Validate against all rules when no key passedvarresult=ruleEngine.ValidateAll(f);// result = false// Only validate against rules with the matching keyvarresult=ruleEngine.ValidateAll(f,"1");// result = true

Validate Any

The calls are the same as the case of validate all, however it returns true if any case is true.

varrules=newList<Rule>{newRule{Key="1",Expression="(f.Age > 3 && f.Income < 50000) || f.NumberOfChildren > 2"},newRule{Key="2",Expression="(f.Age > 3 && f.Income > 100000) || f.NumberOfChildren > 5"}};ruleEngine.AddRules(rules);// Validate against all rules when no key passedvarresult=ruleEngine.ValidateAny(f);// result = true// Only validate against rules with the matching keyvarresult=ruleEngine.ValidateAny(f,"1");// result = true