Input date to webapi - datetime

Question

I am using webapi2. I have a property in model is start date whose datatype is datetime. I want to pass the date as "dd-mm-yyyy" format. But if i send, i am getting 400 bad request. Could you please help me out. Note, I am using Fluent validation for the model validation.
public class Item
{
public DateTime? StartDate { get; set; }
public string Id { get; set; }
}

Answer 1

I want to pass the date as "dd-mm-yyyy"`
You have 3 options.
Option ISO8601
Don't pass it as "dd-mm-yyyy". Pass it instead in ISO8601 format (yyyy-MM-dd). That is the correct way to serialize DateTimes to string and also for then communicating that string representation between tiers. This format is a standard, widely used, unambiguous, and almost all frameworks that I am aware of have built in mechanisms for outputting DateTimes to that format and parsing them from that format.
Displaying a DateTime formatted as "dd-mm-yyyy" is a presentation layer concern and it should stay there and not "bleed" into the other application layers.
Option Formatters
Use custom code, like a Json Converte or an ActionFilterAttribute, to read the incoming DateTime.
Option String
Accept a string parameter instead and handle your own parsing inside the controller's method.
I honestly do not recommend the last 2 options. Instead use ISO8601: a standard, unambiguous, widely accepted means of communicating a DateTime.

Answer 2

I have created a custom value provider factory and am using the default model binding.
public class OrderValueProviderFactory<T> : ValueProviderFactory where T : class
{
public override IValueProvider GetValueProvider(HttpActionContext actionContext)
{
var querystring = actionContext.Request.GetQueryNameValuePairs().ToDictionary(x => x.Key.ToLower(), x => x.Value);
return new OrderValueProvider<T>(querystring);
}
}
public class OrderValueProvider<T> : IValueProvider
{
readonly Dictionary<string, string> querystring;
public OrderValueProvider(Dictionary<string, string> _querystring)
{
querystring = _querystring;
}
public bool ContainsPrefix(string prefix)
{
return true;
}
public ValueProviderResult GetValue(string key)
{
T obj = (T)Activator.CreateInstance(typeof(T));
PropertyInfo[] properties = typeof(T).GetProperties();
foreach (var property in properties)
{
if (property.PropertyType == typeof(string))
{
property.SetValue(obj, querystring.GetStringValue(property.Name.ToLower()));
}
else if (property.PropertyType == typeof(DateTime?))
{
property.SetValue(obj, querystring.GetDateTimeValue(property.Name.ToLower()));
}
else if (property.PropertyType == typeof(int))
{
property.SetValue(obj, querystring.GetIntValue(property.Name.ToLower()));
}
}
return new ValueProviderResult(obj, "", CultureInfo.InvariantCulture);
}
}