Determine If An Object Is A DateTime?
Oct 22, 2010The following works fine in c# (assuming value is an object):
if (value is DateTime)
What is the equivalent check for VB.NET?
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How To Determine If DateTime Is Not Set
Jan 11, 2010In VB6 if I wanted to see if a datetime field wasn't set, I could do something like if myDate = 0 then. I tried that with VB.NET and it can't compare to an integer. How do we do this now? I found the Ticks property, so if myDate.Ticks = 0 does seem to work, but I'm not sure if that's the "right" way to do it. None of the other things I've tried have been successful.
Dim dt As New DateTime
If dt.Ticks = 0 Then MsgBox("dt.Ticks = 0") 'this fires
If IsDBNull(dt) Then MsgBox("IsDBNull(dt)") 'doesn't fire, so no good
If Not IsDate(dt) Then MsgBox("Not IsDate(dt)") 'doesn't fire, so no good
'If dt Is Nothing Then MsgBox("dt is nothing") 'not legal syntax
Determine Local Representation Of A Specific GMT Datetime?
Nov 12, 2010I want to get the date value for
Nov 1, 2010 00:00:00 GMT
expressed in my local time.What is the best way? Currently, I am doing this:
Dim NovGmt As Date = New Date(2010, 11, 1, 0, 0, 0)
Dim Nov1AsLocal As Date = GetGmtExpressedAsLocal(NovGmt)
Private Function GetGmtExpressedAsLocal(ByVal gmtDate As Date) As Date
[code].....
tell me difference between the Date and DateTime datatypes? Is DateTime newer than Date or is it just a synonym for Date? If the latter, why have both?
DateTime - Call To Determine Daylight Savings Time?
Sep 3, 2010Is there a way in VB.Net to determine if the timezone the current system has daylight savings time in effect? Of course I can get the offset from GMT using the "z"/"zz" formatting option, but that doesn't tell me if DST is in effect for the current timezone or if the current timezone is in standard time...or if DST/Standard time aren't even an issue in the timezone for the system.
View 4 RepliesManipulate The Dates To Determine Which Date Will Be 30 Days More Then The Datetime Control?
Sep 17, 2011how to manipulate the dates to determine which date will be 30 days more then the datetime control I have on my form. i need to take the chosen date from the DateTime control, and determine what date it will be in 30 days. Eventually I will use this process to search through the database to print monthly reports.
View 4 RepliesDetermine Which Object In An Object Graph Caused A SerializationException?
Jan 12, 2011I'm deserializing an object and in certain cases it works fine, however in others it fails. The exception is essentially meaningless to me, but there has to be a way to figure out where exactly it failed so i redirect my debugging.
[Code]...
Determine If List(Of Object) Contains Control Object ?
Nov 8, 2010How to know if a List(Of T) contains any control object without using a loop ?This doesn't work
Dim lstObject As New List(Of Object)
lstObject.Add("STRING")
lstObject.Add(2)
[code].....
Set The DateTime Object To The Date?
Nov 27, 2009how can i set the DateTime object to the date i want? dim DT as DateTime
DT.Date="2/2/2004 12:00:05"
Using DateTime Picker Object?
Jul 22, 2009I have a datetimepicker object and a label. Now i want when i choose a date from datetimepicker the label.text to be the next month of the chosen date. I wrote the following code, but it doesn`t work. What is the problem with it?
Private Sub DateTimePicker42_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles DateTimePicker42.ValueChanged
Dim dateincome As Date
[Code].....
.net - Determine Is An Object Is A Structure?
Mar 4, 2011I'm looking for a similar "IsStructure" function. Is there some other way to determine if T is a structure but not an intrinsic type?
Public Shared Function MySub(Of TData)(ByVal t As TData) As TData
Dim IsClass As Boolean
IsClass = GetType(TData).IsClass
End Function
Note that using IsPrimitive and IsValueType on Nullable(Of Integer) and a Structure returns the same results, False and True, respectively.
.net - Determine The Size Of An Object?
Aug 22, 2011Public Class A
Private aa As Integer
Dim bb As Integer
Public cc As Integer
[code]....
what is the size of the object oA?and what if Class A and B contain methods?(I meant the size of object)what if inherited class B contains overridden methods?(size of object)what if inherited class B contains variables with same name as in Class A?(size of object)I need theoretical answer. Does those access specifiers Private,Dim,Public make any difference in allocating memory because of their different scopes?On what basis memory is allotted for a method? etc.
C# - DateTimeFormat - Output From A DateTime-Object
Sep 15, 2010I dont get following desired output from a DateTime-Object: 2010-03-29 13:15:00
My default localization is de-DE, so a simple ToString gives me: 29.03.2010 13:15:00
What I've tried is to create a DateTimeFormatInfo Object from US-Culture and use its DateTimePatterns but without success:
Dim usDateFormat As Globalization.DateTimeFormatInfo = New Globalization.CultureInfo("en-US", False).DateTimeFormat
usDateFormat.DateSeparator = "-"
ruleResult.Claim.Last_Updated_Date.ToString(usDateFormat.ShortDatePattern)
Output: 3.29.2010
What is the best way (readable,fastest) to get my desired DateTimeFormat(i need sometimes the short Date and sometimes the Date and Time like in my example above)?
Why does my DateTimeFormatInfo approach not work and makes it a performance difference when using the String.Format or ToString("yyyy-MM-dd HH:mm:ss") solutions instead of a private shared(static) DateTimeFormatInfo-Object? I'm calling this function at least 30k times and there are many Dates to format inside.
How To Retrieve DateTime Object From Database
Feb 23, 2009I have a problem in retrieving dateTime object from the database. I have this :
Return CBO.FillCollection(Of ObjectInfo)(CType(DataProvider.Instance().ExecuteReader("sp_SelectAll"), IDataReader))
Then When I want to display the date from the collection I get from the stored procedure. the date was truncated. It shows only the timein the ObjectInfo..there is a field call _mydate as DateTime.
String To A Date Or DateTime Object?
Dec 11, 2010I have some some dates as strings in the format dd/mm/yyyy which I need to convert to DateTime object.uggest a simple routine which I can use inside a Loop which produce these Strings.
View 2 RepliesDetermine The Type Of A Passed Object?
May 19, 2009I am still developing this function, but here is what I am intending it to do. This function will accept an Object, then try to determine its type. There are a specific set of types I am looking for: Integer, Boolean, Date, String. What I have so far is pretty privative, but it seems to be working so far:
Private Function DataType(ByVal entry As Object) As ValueType
Try
If IsNumeric(entry) Then
[Code].....
Determine Type Of Object In A Collection?
Oct 28, 2009I can't figure out how to determine the type of an object in a collection. I want to do a For Each ... Next loop over the items in the DropDownItems collection of a ToolStripMenuItem. For those items that are ToolStripMenuItems themselves I want to take some kind of action. (The collection can contain other types of items, such as ToolStripSeparators). So I need to say something like: If Typeof(item) = ToolStripMenuItem Then .
View 1 RepliesDetermine Whether Graphics Object Is For A Printer?
May 11, 2009We would like to know whether there is any way to interrogate a Graphics object and determine whether it is to be used to print or to render to some other canvas. We're aware of an API call that can be used but would prefer to avoid that route if possible. There's also the possibility of simply passing a flag in with the Graphics object that is True from a PrintPage event handler and False from elsewhere, but that's not ideal either. We're looking for a managed property or method accessible via the Graphics class itself, but nothing's jumping out.
View 20 RepliesDetermine What Type Of Object Is The Sender Of An Event?
Nov 25, 2011Heres my sub:
Dim onThisTable as String ="Name"
Private Sub skill_mouseHover(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button1.MouseHover, button2.MouseHover, panel1.MouseHover, panel2.MouseHover, pbox1.MouseHover
[Code]....
Now I wish to give onThisTable a different value depending what the user pass over (panel or a pbox or a button) but I cant find what is the correct way to compare what type it is ...
Private Sub skill_mouseHover(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button1.MouseHover, button2.MouseHover, panel1.MouseHover, panel2.MouseHover, pbox1.MouseHover
[Code]....
VS 2008 : Passing MySQL Parameter As Object Instead Of DateTime?
Jun 13, 2011I am having trouble with a mySQL query with the .NET connector. When I create the query, it automatically creates my parameters as objects. I usually change the type to the correct type, which in this case is Date, but I get different results passing in the parameter as a date.When I do "Preview Query" as an object, I get the correct results, but bad results as a Date. I would just leave them as objects, but it errors out when I try to pass a date in.Here's the part of my query that I'm having trouble with:
(Tickets.Resolved >= str_to_date(@startDate, '%m/%d/%Y')) AND (Tickets.Resolved <= str_to_date(@endDate, '%m/%d/%Y')) AND
(Tickets.Status = 'resolved' OR
Tickets.Status = 'rejected')
Determine That An Object (button) Make Collusion With Clone Of Itself
Jul 10, 2011Let's say we have object A and object B (Picturbox for e.g) Iwant to move A from its position to B's position straightly .what is the mathmatical equalation to get the X,Y coordinator that A must move from its position straightly to B's positionI have another thing ,I would like to know how can I determine that an object (button for e.g) make collusion with a clone of itself.
View 1 RepliesDetermine The Type Of Object To Use To Store A Linq Query?
Jul 3, 2010I am using VB .Net for this, so I don't have access to var or this would be a simple matter.Right now my query is as follows
[code]...
So I used this query in LinqPad to help me determine what the object would look like. I got back a IOrderQueryable(Of RSError) which then contained a IGrouping(Of String, RSError) for each grouped collection of objects returned by the query.However I ended up with the current object type of errors as IOrderedQueryable(Of IGrouping(Of String, RSError)) because of the cast error I am getting in VS.
[code]...
I'm not sure how to get rid of the VB$AnonymousType_1 Part of the returned object.Am I even on the right track here or am I missing something completely?
Using Datatype Object And Determine Datatype In Class Property - Several Integers Columns That Are Null In The Db?
Mar 8, 2010anything wrong with using datatype object and determine datatype in class property? I have a typed dataset and it has several integers columns that are null in the db. and when I make a call it throws exception.is there anythign wrong with setting it as object in my dataset.. changing the throw exception property to Nothing and passing it to my property as integer?
for each row in myDS.DataTable
cRate.CustID = row.CustID
next row
and in my class
Public Property CustID() As Integer
Get
Return _custID[code].............
.net - Determine If "object Is IEnumerable" (C# Syntax)?
Dec 1, 2011I've seen a lot of posts for how to do this in C#, but I'm working in VB and they don't work and I can't seem to get them to convert. Anyone know this? C# is something like: if (x is IEnumerable)
[Code]...
Convert String To Datetime & Calculate The Datetime?
Mar 23, 2011how to convert string to datetime and calculate date
View 3 RepliesMatch A Certain DateTime Value With Current System DateTime
May 7, 2010I'm trying to match a certain DateTime value with the current system DateTime. I have a timer and a label on a form. Timer interval is set to 1000. When the form loads, the timer starts ticking. As soon as the current DateTime matches the value of the variable, it shows a message in the label. When I'm writing the following code, the values don't match even if the current system DateTime is equal to the variable. Label1 isn't showing 'Times Matched':[code]The default format of 'Now' is the same as I have stored in dtmVar variable. So there's no question of format mismatch. Does that mean 'Now' is not actually a DateTime property? Provided, my O.S. is Windows Vista Ultimate and all date/time settings are set to default.
View 1 RepliesMatch A Certain DateTime Value With The Current System DateTime?
May 1, 2010I'm trying to match a certain DateTime value with the current system DateTime. I have a timer and a label on a form. Timer interval is set to 1000. When the form loads, the timer starts ticking. As soon as the current DateTime matches the value of the variable, it shows a message in the label.
When I'm writing the following code, the values don't match even if the current system DateTime is equal to the variable. Label1 isn't showing 'Times Matched':
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
Dim dtmNow As DateTime
[Code]....
Why is it so? The default format of 'Now' is the same as I have stored in dtmVar variable. So there's no question of format mismatch. Does that mean 'Now' is not actually a DateTime property? Provided, my O.S. is Windows Vista Ultimate and all date/time settings are set to default.
Update Datetime Field With Empty Datetime?
Aug 8, 2011datetime1 and datetime2now two fields are have data ( date )in table recordi want to update only datetime2 is an emptyi am using visual basic 2010 ( visual studio 2010
View 1 RepliesC# - Compare Datetime.Now With A Datetime Variable
Dec 27, 2010I try to compare Datetime.Now with a Datetime variable I set, using the Datetime.CompareTo() method. I use a timer to compare these every second and display the result, but as the current time approaches the time I set, the result changes from 1 to -1, but never 0, which means these two are never equal. I'm suspecting the Datetime structure contains milliseconds?
View 7 RepliesChallenge - DateTime Minus DateTime?
Mar 14, 2011Assume the following program is started at 1:59:01 AM on 3/13/2011 in the United States. The first time Timer1 ticks what will be the value of the TimeSpan (ts)?
Public Class Form1
Private Sub Timer1_Tick(sender As System.Object, _
e As System.EventArgs) Handles Timer1.Tick
[code].....
VS 2010 Add Datetime Into Sql - Datetime - Field
Jan 29, 2011I'm trying to add the date and time of Today into a Sql-database-field that has the datetype datetime.
[Code]...
the msgbox gives me the following result: 29/01/2011 18:49:21 my sqlException gives me the following error: 102 - Incorrect syntax near '18'. Is it better that i set the datatype to char in my sql database? It's maybe a bit easier? When I do that, can I calculate with these date?
