C# Dynamic Linq 처리하기

C# Dynamic Linq 처리하기

 

https://dynamic-linq.net/

Dynamic LINQ

dynamic linq 는 동적 쿼리를 동적 문자열로 처리할 수 있도록 해줍니다.

 

아래처럼 Linq 식을 보통 사용하게 되지만

var result = context.Customers
     .Where(c => c.City == "Paris")
     .ToList();

dynamic linq 를 이용하면 아래처럼 사용할 수 있습니다.

var resultDynamic = context.Customers
     .Where("City == \"Paris\"")
     .ToList();

 

사용하기 위해선 System.Linq.Dynamic.Core Nuget package 를 설치합니다.

 

아래는 TestData Class 를 정의하여 사용하는 방법의 예시입니다.

public class TestData
{
    public string Name { get; set; }
    public int Age { get; set; }
    public string Data1 { get; set; }
    public string Data2 { get; set; }
    public int intData1 { get; set; }
    public int intData2 { get; set; }
}

List<TestData> testDataList = new List<TestData>();

// 사용 예시
var queryableData = testDataList.AsQueryable();

var where = queryableData.Where("Name == @0", "NAME0").ToList();

var avg = queryableData.Aggregate("Average", "intData1");

var and = queryableData.Where("Name == @0 and intData1 > @1", "NAME0", 3).ToList();

var select = queryableData.Select("new { Name, Data1 }").ToDynamicList();

var orderedDynamic = queryableData.OrderBy("Name, intData2").ToList();

동적 문자열로 쿼리가 가능해  다양한 조합의 쿼리식을 처리할 수 있습니다.

 

GroupBy 도 아래처럼 처리할 수 있습니다.

List<dynamic> testDynamicList = new List<dynamic>();

var queryableData = testDynamicList.AsQueryable();

// 싱글 컬럼 GroupBy
var onColumnGroups = queryableData.GroupBy("Name");

foreach (IGrouping<object, object> group in onColumnGroups)
{
    string Key = group.Key.ToString();
    var dataList = group.ToList();

    Console.WriteLine($"{Key} : {dataList.Count()}");
}

// 멀티 컬럼 GroupBy
var multiColumnGroups = queryableData.GroupBy("new (Name as Name, Data1 as Data1)");

foreach (IGrouping<object, object> group in multiColumnGroups)
{
    string Key = group.Key.ToString();
    var dataList = group.ToList();

    Console.WriteLine($"{Key} : {dataList.Count()}");
}

// 멀티 컬럼 GroupBy + 키값 및 키별 Count
var gResult = queryableData.GroupBy("new (Name as Name, Data1 as Data1)").Select("new(Key, Count() AS Count)");

foreach (dynamic result in gResult)
{
    Console.WriteLine($"{result.Key} : {result.Count}");
}

// 멀티 컬럼 GroupBy + 특정 컬럼만 선택
var multiColumnGroupsResult = queryableData.GroupBy("new (Name as Name, Data1 as Data1)", "new (Data2 as Data2, intData2 as intData2)");

foreach (IGrouping<object, object> group in multiColumnGroupsResult)
{
    Console.WriteLine($"{group.Key} : {group.Count()}");
}

 

또한 DynamicClass 를 정의하여 사용할 수도 있습니다.

DynamicProperty[] props = new DynamicProperty[]
{
    new DynamicProperty("Name", typeof(string)),
    new DynamicProperty("Birthday", typeof(DateTime))
};

Type type = DynamicClassFactory.CreateType(props);

object obj = Activator.CreateInstance(type);

type.GetProperty("Name").SetValue(obj, "kei", null);
type.GetProperty("Birthday").SetValue(obj, new DateTime(1995, 3, 14), null);

Console.WriteLine(obj);

 

 

전체 코드

using System.Linq.Dynamic.Core;

namespace DynamicLinqTest
{
    internal class Program
    {
        List<dynamic> testDynamicList = new List<dynamic>();
        List<TestData> testDataList = new List<TestData>();

        static void Main(string[] args)
        {
            Program program = new Program();
            program.SampleData(100);
            program.DynamicClass();
            program.BasicQuery();
            program.GroupBy();
            program.Expression();
        }

        private void SampleData(int count)
        {
            for (int i = 0; i < count; i++)
            {
                TestData testData = new TestData()
                {
                    Name = "NAME" + (i / 10),
                    Age = i,
                    Data1 = "Data1_" + (i / 5),
                    Data2 = "Data2_" + i,
                    intData1 = i + 1,
                    intData2 = count - i,
                };

                testDynamicList.Add(testData);
                testDataList.Add(testData);
            }
        }

        private void DynamicClass()
        {
            DynamicProperty[] props = new DynamicProperty[]
            {
                new DynamicProperty("Name", typeof(string)),
                new DynamicProperty("Birthday", typeof(DateTime))
            };

            Type type = DynamicClassFactory.CreateType(props);

            object obj = Activator.CreateInstance(type);

            type.GetProperty("Name").SetValue(obj, "kei", null);
            type.GetProperty("Birthday").SetValue(obj, new DateTime(1995, 3, 14), null);

            Console.WriteLine(obj);
        }

        private void BasicQuery()
        {
            var queryableData = testDataList.AsQueryable();

            var where = queryableData.Where("Name == @0", "NAME0").ToList();

            var avg = queryableData.Aggregate("Average", "intData1");

            var and = queryableData.Where("Name == @0 and intData1 > @1", "NAME0", 3).ToList();

            var select = queryableData.Select("new { Name, Data1 }").ToDynamicList();

            var orderedDynamic = queryableData.OrderBy("Name, intData2").ToList();
        }

        private void GroupBy()
        {
            var queryableData = testDynamicList.AsQueryable();

            // 싱글 컬럼 GroupBy
            var onColumnGroups = queryableData.GroupBy("Name");

            foreach (IGrouping<object, object> group in onColumnGroups)
            {
                string Key = group.Key.ToString();
                var dataList = group.ToList();

                Console.WriteLine($"{Key} : {dataList.Count()}");
            }

            // 멀티 컬럼 GroupBy
            var multiColumnGroups = queryableData.GroupBy("new (Name as Name, Data1 as Data1)");

            foreach (IGrouping<object, object> group in multiColumnGroups)
            {
                string Key = group.Key.ToString();
                var dataList = group.ToList();

                Console.WriteLine($"{Key} : {dataList.Count()}");
            }

            // 멀티 컬럼 GroupBy + 키값 및 키별 Count
            var gResult = queryableData.GroupBy("new (Name as Name, Data1 as Data1)").Select("new(Key, Count() AS Count)");

            foreach (dynamic result in gResult)
            {
                Console.WriteLine($"{result.Key} : {result.Count}");
            }

            // 멀티 컬럼 GroupBy + 특정 컬럼만 선택
            var multiColumnGroupsResult = queryableData.GroupBy("new (Name as Name, Data1 as Data1)", "new (Data2 as Data2, intData2 as intData2)");

            foreach (IGrouping<object, object> group in multiColumnGroupsResult)
            {
                Console.WriteLine($"{group.Key} : {group.Count()}");
            }
        }

        private void Expression()
        {
            var rangeOfNumbers = Enumerable.Range(1, 100).ToArray();
            var result1 = rangeOfNumbers.AsQueryable().Where("it in (1,3,5,7, 101)").ToArray();

            var values = new int[] { 2, 4, 6, 8, 102 };
            var result2 = rangeOfNumbers.AsQueryable().Where("it in @0", values).ToArray();

            var result3 = rangeOfNumbers.AsQueryable().Where("it % 2 = 0");

            var result4 = rangeOfNumbers.AsQueryable().Select("it % 2 == 0 ? true : false");

        }

        public class TestData
        {
            public string Name { get; set; }
            public int Age { get; set; }
            public string Data1 { get; set; }
            public string Data2 { get; set; }
            public int intData1 { get; set; }
            public int intData2 { get; set; }
        }
    }
}