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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;

public class Program
{
	class ABC
	{
		public string LogId;
		public string Name;
	}

	class XYZ
	{
		public string LogId;
		public string Name;
	}

	public static void Main()
	{
		List<ABC> lstABC = new List<ABC>()
		{new ABC()
		{LogId = "1", Name = "somename1"}, new ABC()
		{LogId = "2", Name = "somename2"}, new ABC()
		{LogId = "3", Name = "somename3"}, new ABC()
		{LogId = "4", Name = "somename4"}, new ABC()
		{LogId = "5", Name = "somename5"}};
		List<XYZ> lstXYZ = new List<XYZ>()
		{new XYZ()
		{LogId = "1", Name = "somename11"}, new XYZ()
		{LogId = "2", Name = "somename22"}, new XYZ()
		{LogId = "3", Name = "somename33"}, new XYZ()
		{LogId = "8", Name = "somename8"}, new XYZ()
		{LogId = "9", Name = "somename9"}};
		var res = lstABC.Where(x => (lstXYZ.Any(y => y.LogId == x.LogId))).Select(x => x.LogId).ToArray();
		foreach (string item in res)
		{
			Console.WriteLine(item);
		}
	}
}