How to compare to list of date in C#?

I have two list of date. I have to compare both list and find missing date. My first list looks like this:

My second list looks like this

I have to find the missing date between the two list :

I tried this

var anyOfthem = firstList.Except(secondList);

But it didn't work. Can anyone help me with this ?

Solution

Well, you could use .Except() and .Union() methods :

        string[] array1 = 
        {
        "2015-07-21",
        "2015-07-22",
        "2015-07-23",
        "2015-07-24",
        "2015-07-25",
        "2015-07-26",            
        };

        string[] array2 = 
        {
        "2015-07-21",
        "2015-07-22",
        "2015-07-23",            
        "2015-07-25",
        "2015-07-26",
        "2015-07-27"
        };

        var result = array1.Except(array2).Union(array2.Except(array1));

        foreach (var item in result) 
        {
           Console.WriteLine(item);
        }

Output : "2015-07-24", "2015-07-27",