格式化C＃对象列表中的所有日期属性

Question

I'm having huge issues with formatting the DateTime of each date property within a list of objects. Here's a few examples of what I've tried so far:

var data = vulnerabilityList.Skip(skip).Take(pageSize).ToList()
    .Select(v => { v.PublishedDate = 
    v.PublishedDate.ToString("dd/MM/yyyy"); return v; });

and

var data = vulnerabilityList.Skip(skip).Take(pageSize).ToList()
    .Select(v => { v.PublishedDate = 
        DateTime.ParseExact(v.PublishedDate.ToString(), "dd/MM/yyyy", 
            CultureInfo.CurrentCulture); return v; });

Ultimately I want the format as 31/12/2017 and it'll be returned as JSON so it seems the data annotations on the vulnerability class are ignored. The first example doesn't compile as obviously it's trying to set a DateTime as a string, but I included it as an example of what I'm looking to do.

Thanks

Answer 1

A datetime is a representation of a date and time using a number, and it doesn't have an inherent format. It's intended for you to format it how you want it when you read it or display it to users. So doing something like this:

v.PublishedDate = (DateTime)v.PublishedDate.ToString("dd/MM/yyyy")

Is only going to set the publish date to dd/MM/yy 00:00:00 (if it did work).

I believe what you'll need to do is either change how you're parsing your JSON in the end, or store the DateTime as a string in a new property for reading.