// Proof for https://stackoverflow.com/questions/77849553/how-to-apply-multiple-conditions-in-datatable-select-in-c-sharp#77849553

​

using System;

using System.Collections.Generic;

using System.Data;

using System.Reflection;

public class Program

{

    public static void Main()

    {

        string json = @"[

  {

    ""id"": 1623,

    ""customer_type_id"": 645,

    ""covered_patient_type"": ""Outpatient"",

    ""expectation"": ""filtered out""

  },

  {

    ""id"": 1624,

    ""customer_type_id"": 645,

    ""covered_patient_type"": ""Inpatient"",

    ""expectation"": ""filtered out""

  },

  {

    ""id"": 1625,

    ""customer_type_id"": 64501,

    ""covered_patient_type"": ""Outpatient"",

    ""expectation"": ""filtered out""

  },

  {

    ""id"": 1626,

    ""customer_type_id"": 64501,

    ""covered_patient_type"": ""Inpatient"",

    ""expectation"": ""selected""

  },

  {

    ""id"": 1627,

    ""customer_type_id"": 64501,

    ""covered_patient_type"": ""Outpatient"",

    ""expectation"": ""filtered out""

  },

  {

    ""id"": 1628,

    ""customer_type_id"": 64501,

    ""covered_patient_type"": ""Inpatient"",

    ""expectation"": ""selected""

  },

  {

    ""id"": 1629, 

    ""customer_type_id"": 64501,

    ""covered_patient_type"": ""Outpatient"",

    ""expectation"": ""filtered out""

  }

]";

        System.Data.DataTable dt = Newtonsoft.Json.JsonConvert.DeserializeObject<System.Data.DataTable>(json);

        System.Data.DataView dvOrg = new System.Data.DataView(dt);

        foreach(System.Data.DataColumn column in dt.Columns)

        {

            Console.WriteLine($"{column.ColumnName}: {column.DataType}");

        }

        Console.WriteLine();

        // example that works:

        Console.WriteLine("Filter By one column: customer_type_id='64501'");

        var filterResult = dvOrg.Table.Select("customer_type_id='64501'", "id DESC");

        foreach(var row in filterResult)

        {

            Console.WriteLine($"ID:{row["id"]}, expectation:{row["expectation"]}, customer_type_id:{row["customer_type_id"]}, covered_patient_type:{row["covered_patient_type"]}"); 

        }

        Console.WriteLine();

        // filter by two columns

        Console.WriteLine("Filter By two columns: customer_type_id='64501' and covered_patient_type='Inpatient'");

        filterResult = dvOrg.Table.Select("customer_type_id='64501' and covered_patient_type='Inpatient'", "id DESC");

        foreach(var row in filterResult)

        {

            Console.WriteLine($"ID:{row["id"]}, expectation:{row["expectation"]}, customer_type_id:{row["customer_type_id"]}, covered_patient_type:{row["covered_patient_type"]}"); 

        }

        Console.WriteLine();

        Console.WriteLine("What if covered_patient_type is an enum?");

        List<PatientData> data = Newtonsoft.Json.JsonConvert.DeserializeObject<List<PatientData>>(json);

        dvOrg = new System.Data.DataView(dt);

        foreach(System.Data.DataColumn column in dt.Columns)

        {

            Console.WriteLine($"{column.ColumnName}: {column.DataType}");

        }

        Console.WriteLine();

        // example that works:

        Console.WriteLine("Filter By one column: customer_type_id='64501'");

        filterResult = dvOrg.Table.Select("customer_type_id='64501'", "id DESC");

        foreach(var row in filterResult)

        {

            Console.WriteLine($"ID:{row["id"]}, expectation:{row["expectation"]}, customer_type_id:{row["customer_type_id"]}, covered_patient_type:{row["covered_patient_type"]}"); 

        }

        Console.WriteLine();

        // filter by two columns

        Console.WriteLine("Filter By two columns: customer_type_id='64501' and covered_patient_type='Inpatient'");

        filterResult = dvOrg.Table.Select("customer_type_id='64501' and covered_patient_type='Inpatient'", "id DESC");

        foreach(var row in filterResult)

        {

            Console.WriteLine($"ID:{row["id"]}, expectation:{row["expectation"]}, customer_type_id:{row["customer_type_id"]}, covered_patient_type:{row["covered_patient_type"]}"); 

        }

    }

}

​

public class PatientData

{

    public int id { get;set; }

    public int customer_type_id { get;set; }

    public PatientType covered_patient_type { get; set; }

    public string expectation { get; set; }

}

public enum PatientType

{

    Inpatient = 0,

    Outpatient = 1

}

public static class DataListExtensions

{

public static DataTable ToDataTable<T>(this List<T> items)

{

    DataTable dataTable = new DataTable(typeof(T).Name);

    PropertyInfo[] Props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);

    foreach (PropertyInfo prop in Props)

    {

        dataTable.Columns.Add(prop.Name);

    }

    foreach (T item in items)

    {

        var values = new object[Props.Length];

        for (int i = 0; i < Props.Length; i++)

        {

            values[i] = Props[i].GetValue(item, null);

        }

        dataTable.Rows.Add(values);

    }

    return dataTable;

}

}