Iterate in two lists with different objects

Question

I am trying to iterate in two list with different objects.I am adding the records to a third list if they complete the following conditions when I compare listTest1 and listTest2

• If the abbrv and the date is the same I am adding the object from listTest2 to listTest3
• If the abbrv is the same but the date is different I am adding the object from listTest2 to listTest3 and I am switching the completed property to true. In addition, I am adding the record from listTest1 to listTest3.
• If the abbrv from listTest1 doesn't exist in listTest2 I am adding the record from listTest1 to listTest3.

I know that it sounds quite confusing that is why I will show you what I am getting and what I am expecting.

I am getting:

I need to get all these records but the duplicate(Test2).

static void Main(string[] args)
{
    Test1 test1 = new Test1() { abbrv = "Test1", date = new DateTime(2017, 11, 12), completed = false };
    Test1 test2 = new Test1() { abbrv = "Test2", date = new DateTime(2017, 12, 17), completed = false };
    Test1 test5 = new Test1() { abbrv = "Test5", date = new DateTime(2017, 12, 12), completed = false };
    Test2 test3 = new Test2() { abbrv = "Test1", date = new DateTime(2017, 11, 12), completed = false, abbrevName = "AbbrvName1" };
    Test2 test4 = new Test2() { abbrv = "Test2", date = new DateTime(2017, 12, 12), completed = false, abbrevName = "AbbrvName2" };
    List<Test1> listTest1 = new List<Test1>();
    List<Test2> listTest2 = new List<Test2>();
    List<Test2> listTest3 = new List<Test2>();
    listTest1.Add(test1);
    listTest1.Add(test2);
    listTest1.Add(test5);
    listTest2.Add(test3);
    listTest2.Add(test4);
    for (int i = 0; i < listTest1.Count; i++)
    {
        for (int a = 0; a < listTest2.Count; a++)
        {
            if (listTest1[i].abbrv == listTest2[a].abbrv && listTest1[i].date == listTest2[a].date)
            {
                if (!listTest3.Any(x => x.abbrv == listTest1[i].abbrv))
                {
                    listTest3.Add(listTest2[a]);
                }
            }
            else
            {
                if (listTest1[i].abbrv == listTest2[a].abbrv)
                {
                    if (!listTest3.Any(x => x.abbrv == listTest1[i].abbrv && x.date != listTest1[i].date))
                    {
                        listTest3.Add(new Test.Test2() { abbrv = listTest2[a].abbrv, date = listTest2[a].date, completed = true, abbrevName = listTest2[a].abbrevName });
                        listTest3.Add(new Test.Test2() { abbrv = listTest1[i].abbrv, date = listTest1[i].date, completed = listTest1[i].completed, abbrevName = string.Empty });
                    }

                }
                else if (listTest1[i].abbrv != listTest2[a].abbrv)
                {
                    if(!listTest3.Any(x => x.abbrv == listTest1[i].abbrv))
                    {
                        listTest3.Add(new Test.Test2() { abbrv = listTest1[i].abbrv, date = listTest1[i].date, completed = listTest1[i].completed, abbrevName = string.Empty });
                    }
                }
            }
        }
    }
}

public class Test1
{
    public string abbrv { get; set; }
    public DateTime date { get; set; }
    public bool completed { get; set; }
}
public class Test2
{
    public string abbrv { get; set; }
    public DateTime date { get; set; }
    public bool completed { get; set; }
    public string abbrevName { get; set; }
}  

Answer 1

You implemented the first two conditions correctly, but the third condition cannot be implemented in the innermost loop: you cannot tell if abbrv from listTest1 exists in listTest2 until your inner loop is over.

Add a bool variable abbrvFound indicating that an abbrv is found. Set it to false before entering the nested loop; if a match is found, set it to true.

After the loop is over, check abbrvFound to decide if you need to add listTest1 object or not.

for (int i = 0; i < listTest1.Count; i++) {
    bool abbrvFound = false;
    for (int a = 0; a < listTest2.Count; a++) {
        if (listTest1[i].abbrv != listTest2[a].abbrv)
            continue;
        abbrvFound = true;
        if (listTest1[i].date == listTest2[a].date) {
            listTest3.Add(listTest2[a]);
        } else {
            listTest3.Add(new Test.Test2() { abbrv = listTest2[a].abbrv, date = listTest2[a].date, completed = true, abbrevName = listTest2[a].abbrevName });
            listTest3.Add(new Test.Test2() { abbrv = listTest1[i].abbrv, date = listTest1[i].date, completed = listTest1[i].completed, abbrevName = string.Empty });
        }
    }
    if (!abbrvFound) {
        listTest3.Add(new Test.Test2() { abbrv = listTest1[i].abbrv, date = listTest1[i].date, completed = listTest1[i].completed, abbrevName = string.Empty });
    }
}