using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

​

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

using Newtonsoft.Json.Converters;

using Newtonsoft.Json.Serialization;    

​

using NUnit.Framework; // Throws NUnit.Framework.AssertionException

​

//https://stackoverflow.com/questions/34191320/string-functions-in-jsonpath

​

    class TestClass

    {

        public static void Test()

        {

            Test1();

            Test2();

            Test3();

            Test4();

            Test5();

            Test6();

            Test7();

        }   

        static void Test1()

        {

            var json =

                """

                {

                "Manufacturers": [

                    {"Name" : "Acme Co"},

                    {"Name" : "Notme Co"},

                ]

                }

                """;

​

            var o = JToken.Parse(json);

            JToken acme = o.SelectToken("$.Manufacturers[?(@.Name =~ /Acme/)]");

            Assert.That(acme != null);

            Assert.AreEqual("{\"Name\":\"Acme Co\"}", acme?.ToString(Formatting.None));

            Console.WriteLine(acme?.ToString(Formatting.None));

        }

        static void Test2()

        {

            var json =

                """

                {

                "Manufacturers": [

                    {"Name" : "Acme Co"},

                    {"Name" : "NotAcme Co"},

                    {"Name" : "Notme Co"},

                ]

                }

                """;

​

            var o = JToken.Parse(json);

            JToken acme = o.SelectToken("$.Manufacturers[?(@.Name =~ /\\bAcme\\b/)]");

            Assert.That(acme != null);

            Assert.AreEqual("{\"Name\":\"Acme Co\"}", acme?.ToString(Formatting.None));

            Console.WriteLine(acme?.ToString(Formatting.None));

        }

        static void Test3()

        {

            var json =

                """

                {

                "Manufacturers": [

                    {"Name" : "ACME Co"},

                    {"Name" : "Notme Co"},

                ]

                }

                """;

​

            var o = JToken.Parse(json);

            JToken acme = o.SelectToken("$.Manufacturers[?(@.Name =~ /(?i)acme/)]");

            Assert.That(acme != null);

            Assert.AreEqual("{\"Name\":\"ACME Co\"}", acme?.ToString(Formatting.None));

            Console.WriteLine(acme?.ToString(Formatting.None));

        }

        static void Test4()

        {

            var json =

                """

                {

                "Manufacturers": [

                    {"Name" : "\nAcme Co"},

                    {"Name" : "Notme Co"},

                    {"Name" : "Notme Co\r\nAcme"},

                ]

                }

                """;

​

            var o = JToken.Parse(json);

            var acme = o.SelectToken("$.Manufacturers[?(@.Name =~ /^(?!.*Acme).*$/)]");

            Console.WriteLine(JsonConvert.SerializeObject(acme,Formatting.None));

​

            Assert.That(acme != null);

            Assert.AreEqual("{\"Name\":\"Notme Co\"}", JsonConvert.SerializeObject(acme,Formatting.None));

        }

        static void Test5()

        {

            var json =

                """

                {

                "Manufacturers": [

                    {"Name" : "Acme At The Beginning"},

                    {"Name" : "Notme Co"},

                    {"Name" : "Not Acme Co"},

                ]

                }

                """;

​

            var o = JToken.Parse(json);

            JToken acme = o.SelectToken("$.Manufacturers[?(@.Name =~ /^Acme/)]"); 

            Assert.That(acme != null);

            Assert.AreEqual("{\"Name\":\"Acme At The Beginning\"}", acme?.ToString(Formatting.None));

            Console.WriteLine(acme?.ToString(Formatting.None));

        }

        static void Test6()

        {

            var json =

                """

                {

                "Manufacturers": [

                    {"Name" : "Acme Co"},

                    {"Name" : "Notme Co"},

                    {"Name" : "Ends With Acme"},

                ]

                }

                """;

​

            var o = JToken.Parse(json);

            JToken acme = o.SelectToken("$.Manufacturers[?(@.Name =~ /Acme$/)]"); 

            Assert.That(acme != null);

            Assert.AreEqual("{\"Name\":\"Ends With Acme\"}", acme?.ToString(Formatting.None));

            Console.WriteLine(acme?.ToString(Formatting.None));

        }

        static void Test7()

        {

            var json =

                """

                {

                "Manufacturers": [

                    {"Name" : "Acme"},

                    {"Name" : "7\nchars"},

                    {"Name" : "Notme Co"},

                    {"Name" : "Ends With Acme"},

                ]

                }

                """;

​

            var o = JToken.Parse(json);

            JToken acme = o.SelectToken("$.Manufacturers[?(@.Name =~ /(?s)^.{7}$/)]"); 

            Console.WriteLine(acme?.ToString(Formatting.None));

​

            Assert.That(acme != null);

            Assert.AreEqual("{\"Name\":\"7\\nchars\"}", acme?.ToString(Formatting.None));

        }

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: {0} ({1}), {2}", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , Environment.Version, Environment.OSVersion);

            Console.WriteLine("{0} version: {1}", typeof(JsonSerializer).Namespace, typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​