Sort List by string converted to int

Question

I have a list of Int saved as String and I would like to order them. I came up with the following solution:

sortList = sortList.OrderByDescending(x => Convert.ToInt32(x.Number)).ToList();

It works perfectly, but only if the list only contains numbers. For example, if there is one item that is a string like "???" the sorting totally fails.

Expectation:

['313', '309', '119', '49', '???']

Result:

['309' '49' '313' '119' '???']

Answer 1

So you need to use int.TryParse() and return a low value for invalid strings:

sortList = sortList.OrderByDescending(x =>
    {
        int i;
        return int.TryParse(x.Number, out i) ? i : int.MinValue;
    });

I use OrderByDescending instead of OrderBy as the expected result you showed is in descending order.