assigning Null value to datetime in C#

Hi,

How can I assign Null value to datetime?

Re: assigning Null value to datetime in C#

Since DateTime is a value type (like int), a Null value cannot be assigned to it. In this instance many people use DateTime.MinValue or DateTime.MaxValue instead.

Re: assigning Null value to datetime in C#

You can use Nullable Types to achieve that.

DateTime? dateSample;
dateSample.Value = null;

//or

Nullable<DateTime> dateSample2;
dateSample2.Value = null;

Re: assigning Null value to datetime in C#

n.ocampo

You can use Nullable Types to achieve that.

DateTime? dateSample;
dateSample.Value = null;

//or

Nullable<DateTime> dateSample2;
dateSample2.Value = null;

Nullable types is correct, but your example is not :-( You cannot assign null to the Value property, it is of type 'DateTime'.

DateTime? dateSample;
            dateSample = null;
            //or 
            Nullable dateSample2;
            dateSample2 = null;

Re: assigning Null value to datetime in C#

Nullable<DateTime> _myDateTime;

will work, you should be able to set it to null

Check for nulls:

if (object.myDateTime != null)

if (object.myDateTime.HasValue)

hope this helps

Re: assigning Null value to datetime in C#

iainpb

Nullable<DateTime> _myDateTime;

will work, you should be able to set it to null

Check for nulls:

if (object.myDateTime != null)

or

if (object.myDateTime.HasValue)

This must be my picky day ;-) The example does not work. 'object' is a reserved word, the name used in the sample is _myDateTime, so it should be:

if (_myDateTime != null) ...

if (_myDateTime.HasValue) ...

Re: assigning Null value to datetime in C#

Re: assigning Null value to datetime in C#

m_Date = _Date != null ? _Date : (Nullable<DateTime>)null;

Re: assigning Null value to datetime in C#

You can also write code like

m_Date = dr.IsDBNull(dr.GetOrdinal("_Date")) ? (DateTime?)null : (DateTime?)Convert.ToDateTime(dr["_Date"]);

Re: assigning Null value to datetime in C#

you need to assign like this in C#

DateTime? variablename = null;