Assigning null value to datetime object

Question

0.00/5 (No votes)

See more:

VB

Hi, can anyone explain me how to assign a null value to a datetime object in vb.net.
thanks in advance

Posted 17-Jul-11 21:25pm

s.faizaan7

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Toniyo Jackson · Accepted Answer · 2011-07-17T21:27:00

Solution 1

Dim dt as DateTime = System.DBNull.Value

Posted 17-Jul-11 21:27pm

Toniyo Jackson

Updated 17-Jul-11 21:28pm

v2

Comments

s.faizaan7 18-Jul-11 3:32am

no, it gives error as value type of dbnull cannot be converted to date.
The problem is i have a date time picker with a checkbox, whenever the checkbox is unchecked the dtp is disabled. at this point of time i want to assign null value to my dtp

Simon_Whale 18-Jul-11 4:54am

You can't assign null value to a date you need to use the nullable(of datetime) to make it work e.g

Dim dt as nullable(of datetime) = nothing

Cimak666 12-Feb-19 15:37pm

great idea ! ! ! Works perfect!

s.faizaan7 19-Jul-11 6:34am

thank u...it works

Toniyo Jackson 19-Jul-11 6:38am

You are welcome :)

Frankie-10589807 25-Jun-16 10:59am

Trying to Pass a null value to sql database from an empty textbox control in vb.net
Here is the code i've tried:

dim MyItem as new ItemRegClass
Dim DateReturned as date
If txtDateReturned.Text.Trim = "" Then
MyItem.DateReturned = DBNull.Value
Else
MyItem.DateReturned = CDate(txtDateReturned.Text.Trim)
End If

The error message i got is "Value of type 'System.DBNull' cannot be converted to 'Date'."

Any help with this will be appreciated.
Thanks

Abhinav S · Accepted Answer · 2011-07-17T21:30:00

Solution 2

If you are using .Net 2.0 or greater, you can always use a nullable type.

Declare your field as DateTime? dt;
Then set dt = null;

UPDATE:
In VB.NET, use this:

Dim dt As System.Nullable(Of DateTime)
dt = Nothing

Posted 17-Jul-11 21:30pm

Abhinav S

Updated 17-Jul-11 21:36pm

v2

Comments

Toniyo Jackson 18-Jul-11 3:32am

He is using VB.Net?

Member 10235047 12-Nov-13 4:17am

dtpscheDt.Text = Null

Tarun.K.S 18-Jul-11 3:37am

Done!

Toniyo Jackson 18-Jul-11 3:40am

This will not work. Please see OP comment in my answer

Tarun.K.S 18-Jul-11 3:38am

5 for the solution.

s.faizaan7 18-Jul-11 3:39am

still no go. it is giving the following error
'SqlDateTime overflow. Must be between 1/1/1753 12:00:00 AM and 12/31/9999 11:59:59 PM.' when i'm trying to execute the sqlcommand

s.faizaan7 18-Jul-11 3:41am

yes Toniyo i'm using vb.net in front end from which i'm passing this value to my dll which is in c#

kmh72756 20-Jul-11 1:27am

You need to redefine your column in SQl Server to ALLOW NULL.