Q:

Unit testing body of properties

This is my Code
public class AssistanceRequest : DocumentBase
{
    public AssistanceRequest()
    {
        RequestTime = DateTime. Now;
        ExcecutionTime = DateTime. MaxValue;
    }

    public AssistanceRequest(int amount, string description, DateTime?  requestTime) : this()
    {
        //Check for basic validations
        if (amount <= 0)
            throw new Exception("Amount is not Valid");
        this. Amount = amount;
        this. Description = description;
        this. RequestTime = requestTime ??  DateTime. Now;
    }

    private long Amount { get; set; }

    private DateTime requestTime { get; set; }

    public DateTime RequestTime
    {
        get { return requestTime; }
        set
        {
            if (value ! = null && value < DateTime. Now)
                throw new Exception("Request Time is not Allowed");
            requestTime = value;
        }
    }

As you can see I have a validation in my Set body.  I need to test it. 
and I try to call the constructor in my Tests.  but I get Exception in Constructor ( act ) before assertion.  How to make my tests right? 
This is my Test:
[Theory]
    [MemberData("RequestFakeData")]
    public void Should_Throw_Exception_RequestDate(int amount, string description, DateTime requestDate)
    {
        var manager = new AssistanceRequest(amount,description,requestDate);
        manager. Invoking(x => x.SomeMethodToChangeRequestTime).ShouldThrowExactly<Exception>()
    }

    public static IEnumerable<object[]> RequestFakeData
    {
        get
        {
            // Or this could read from a file. :) 
            return new[]
            {
            new object[] { 0,string. Empty,DateTime. Now. AddDays(1) },
            new object[] { 2,"",DateTime. Now. AddDays(-2) },
            new object[] { -1,string. Empty,DateTime. Now. AddDays(-3) },
            };
        }
    }

I get the Error in about this Line:
var manager = new AssistanceRequest(amount,description,requestDate);

the constructor is trying to set the property so it gets the Exception.  and does not get to the assertion. 
My question is: How can I test this without changing my constructor? 

A:

I found the solution and for those who check later on I put it right here. 
If we want to test these types of Exceptions in xUnit it may get a little tricky.  
I read an article here: http://hadihariri.com/2008/10/17/testing-exceptions-with-xunit/
it helped me out to edit my Code and get the right answer. 
I changed my Tests like this:
[Theory]
    [MemberData("RequestFakeData")]
    public void Should_Throw_Exception_RequestDate(int amount, string description, DateTime requestDate)
    {
        Exception ex = Assert. Throws<Exception>(() => new AssistanceRequest(amount,description,requestDate));
        Assert. Equal("Request Time is not Allowed",ex. Message);
    }

    public static IEnumerable<object[]> RequestFakeData
    {
        get
        {
            return new[]
            {
            new object[] { 1,string. Empty,DateTime. Now },
            new object[] { 2,"",DateTime. Now. AddDays(-2) },
            new object[] { 1,string. Empty,DateTime. Now. AddDays(-3) },
            };
        }
    }

hope it would be helpful.