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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.Select(x => x.LogId).Intersect(lstXYZ.Select(y => y.LogId));
		foreach (string item in res)
		{
			Console.WriteLine(item);
		}
	}
}