DsRule

DsRule stands for Domain-specific Rule.

What is DsRule?

DsRule is used to parse domain-specific expression (in string) to Linq Expression and execute.

Install

dotnet add package DsRule

Usage

The simplest case is parsing below expression

var result = DsRuleExecutor.Execute<int>("1 + 1");
// result is 2

A more complicated example for domain-specific expression

var model = new Employee { FirstName = "Vincent", LastName = "Any", Age = 30 };
var dsExpr = "FirstName = 'Vincent' AND Age > 25";

var result = DsRuleExecutor.Execute<Employee, bool>(model, dsExpr);
// 'result' is true

You can also use expresion in Where caluse

var employees = new List<Employee> { ... }; // A list of employees
var filtered = employees.Where("FirstName = 'Vincent' AND Age > 25");

For more examples, please refer to Examples

Domain-specific language grammar

Kind	--	Description
Comparand	+, -, *, /
Comparison	<, >, <=, >=, =, !=, <>
Keyword	not, and, or, true, false, null
Keyword	in	Used for Array
Keyword	now, today	Will be parsed to DateTime.Now and DateTime.Today