C# compare two List collection objects

	namespace MyPOC
	{
	partial class TestLists
	{
	public void GetDeltaData()
	{
	List<Emp> listSource = new List<Emp>();
	listSource.Add(new Emp() { EmpID = 4, EmpName = "D" });
	listSource.Add(new Emp() { EmpID = 1, EmpName = "A1" });
	listSource.Add(new Emp() { EmpID = 2, EmpName = "B" });
	List<Emp> listTarget = new List<Emp>();
	listTarget.Add(new Emp() { EmpID = 1, EmpName = "A", isActive = true });
	listTarget.Add(new Emp() { EmpID = 3, EmpName = "C", isActive = true });
	listTarget.Add(new Emp() { EmpID = 2, EmpName = "B", isActive = true });
	List<Emp> listDelta = new List<Emp>();
	bool isExistInTraget = false;
	//loop tr all listSource
	foreach (var sour in listSource)
	{
	//loop tr all listTarget
	foreach (var tar in listTarget)
	{
	if (tar.EmpID == sour.EmpID)
	{
	isExistInTraget = true;
	if (tar.EmpName != sour.EmpName)
	{
	//Add EmpID, EmpName to listDelta and Active = true from source// This is update action
	listDelta.Add(new Emp() { EmpID = sour.EmpID, EmpName = sour.EmpName, isActive = true });
	//remove tar from listTarget
	listTarget.Remove(tar);
	}
	else
	{
	//remove tar from listTarget
	listTarget.Remove(tar);
	}
	break;
	}
	}
	if (!isExistInTraget)
	{
	//New item from listSource
	//Add EmpID, EmpName to listDelta and Active=true
	listDelta.Add(new Emp() { EmpID = sour.EmpID, EmpName = sour.EmpName, isActive = true });
	}
	}
	//By this time: listTarget will have only records, which are not there in Source system, mean we have to deactivate these records from Target
	foreach (var tar in listTarget)
	{
	//Add each record to listDelta by Active=false
	listDelta.Add(new Emp() { EmpID = tar.EmpID, EmpName = tar.EmpName, isActive = false });
	}
	}
	}
	public class Emp
	{
	public int EmpID { get; set; }
	public string EmpName { get; set; }
	public bool isActive { get; set; }
	}
	}

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