Have An Optional Parameter Of The Type List?
Sep 25, 2009
Is it possible to have an optional parameter of the type list?Ex.
Private Function TestFunction(Optional ByRef MyList As List(Of Double))
The real problem is giving the list a default value. When dimming a new list, you can use the code below to give it a starting value:
Dim MyList As New List(Of Double)(New Double() {1, 2, 3, 4, 5})
But even after trying many variations of the above code, I cannot get it to work as an optional parameter.
View 16 Replies
ADVERTISEMENT
Mar 22, 2012
I want to pass an optional parameter to a function of type System.Drawing.Color. The problem I am having is that when I declare the function it says "Constant expression is required" but I have tried variations of the following, including integers, full qualified indentifiers, even old vbWhite constants to no avail.
[Code]...
View 14 Replies
Feb 14, 2011
say I have two POCOs I'm using in EF code first
Public class C1
property F1 as integer
End Class
Public class C2
property F2 as String
End Class
I want to have a function that will create a list either of C1 or C2, to be used in some generic operation, such that
[Code]...
View 1 Replies
Mar 14, 2012
How can i create a optional parameter in C# as we create in VB.Net
Public Sub Demo(ByVal a As Integer,Optional ByVal b as integer=3)
End Sub
I want to declare this in C#
[code].....
View 2 Replies
Nov 1, 2010
Is there a way to pass an optional parameter to a webservice, instead of having to overload the method?If the webservice user is accessing the webservice directly, I want to do ActionA, if the user is accessing the webservice through my web interface, I want to do ActionA + ActionB.
View 1 Replies
Nov 3, 2010
how can use color as an optional parameter in a sub/function?This doesn't work.
Code:
Public Sub WriteLog(ByVal sText As String, Optional ByVal lColor As Color = Color.Blue)
'Code
End Sub
View 5 Replies
May 27, 2010
I have come across something confusing or potentially a bug in Visual Studio 2010 when defining an interface in my VB application: When defining an interface method with a default parameter of type Double, using the Double.NaN constant as the default value causes the code editor/intellisense/precompiler some issues.The following code underlines "INaNTest" and "INaNTest.DoSomething" claiming that 'DoSomething' cannot implement 'DoSomething' because there is no matching sub on interface 'INaNTest':
[code]...
where now "NaN" has been divorced from the "Double." prefix and underlined ('NaN' is not declared. It may be inaccessible due to its protection level.) The code editor has inserted invalid code again.Is there a correct solution to using Double.NaN as the default value for a method as defined on an interface, in VB.net, or is there a fundamental reason why this is impossible?
View 2 Replies
Mar 22, 2011
I have an object, called 'PERSON' This person object has a title, firstName & Surname property as well as many other which are at the moment irrelevant. It also has a read only property called Fullname which concatenates the two or three parameters mentioned above depending on an optional parameter 'withTitles' passed over when you call PERSON.FULLNAME
PERSON.FULLNAME(true) <- Will add titles if there are any
PERSON.FULLNAME(false) <- Will give the name without the title
Public ReadOnly Property FullName(Optional ByVal withTitle As Boolean = False) As String
[Code]...
I get an error: PERSON does not contain a property of 'FullName'. If I change this to any other property that does not take a parameter it works as expected. Now I'm guessing that the binding procedure can't handle optional or mandatory parameters for object properties, is this right? Is there a better way to do it? I thought about looping through the collection to add them manually but that kinda defeats the object of DataBinding!
View 1 Replies
Jul 28, 2010
I have a problem during defining a Sub routine in VB.Net. I am defining a sub routine which is as under
Private Sub ActivateControls(rdbutton as RadioButton, Optional txt as Textbox, Optional txt2 as Textbox)
End sub
When I call this sub routine It gives me the Error that Each Optional Parameter must specify a default value. So, Here I can't understand that what can be the default value of a textbox. What default value I can use here to remove this error.
View 6 Replies
Apr 19, 2012
I have traditionally coded empty strings like this "", but for a couple of years now, I have been using String.Empty.I also normally never use optional parameters, but I'm refactoring a solution that's tied into my ERP, and I don't want to break anything. One of the changes was to add a parameter to proc, which pushes a new parameter into the method from which it is called. I coded it like this:
Optional BackReferenceID As String = String.Empty
But I got a syntax error "Constant expression is required." I guess String.Empty is non-deterministic??? Anyway, it seems like a bug. The workaround is of course to use double quotes.
View 1 Replies
Sep 22, 2010
I think this is a pretty basic question, but I just want to clarify. If I have a variable with a null value, and pass it as a parameter that is optional, will the parameter get the null value, or the default value?
dim str As String = "foo"
dim obj As Object
//call 1
[code].....
View 1 Replies
Nov 13, 2011
I tried the following, but i get the error
constant expression is required
Public Sub ExampleSub(ByVal Test as string,
Optional ByVal fromDate As System.Nullable(Of DateTime) = Date.Today)
'A Great sub!
[Code].....
View 3 Replies
Apr 10, 2009
I am hardcoding an insert statement to a database, based on certain details a user enters into a windows form. The form has a few textbox and datetimepicker controls for the purpose. This form enters a single row in a single table in the database.The table has a few possible null columns defined, in those cases where the user does not have any data for those columns at that particular time.
I have to provide controls for passing data to those null columns nevertheless. In my case, I have two such columns that accept null values, and two corresponding controls - a textbox and a datetimepicker. The datetimepicker has a checkbox added to it so that if it is supposed to be null it doesn't pass the default current date value, and remains unchecked to explicitly specify that it is supposed to be null. By default it is unchecked.
My code is structured as follows:
Form1:
'the sub referenced here resides in a dll file in my dataaccesslayer code, and in my actual example is referenced properly.
'I have shortened the code here for simplicity
[code]....
Now it gives me an error whenever the code comes to the executenonquery(), and says something to the tune of "SqlDateTimeOverflow. Must be between 1/1/1753 12:00:00 AM and 12/31/9999 11:59:59 PM."
I think the value of 'Nothing' from the subprocedure's paramter is not being assigned to the sqlcommand's parameter as a database NULL, which is what I need to pass to the database.I know instead of using optional parameters I can easily create overloaded subprocedures where one sub allows not passing values where the column(s) is supposed to null and other overloaded subs permit combinations of which column(s) are null or not. But it is simple as long as there is just one, or at the most two null columns in a table. If I have dozens of null values in a table that the user can choose to enter or not in a data entry form?
View 7 Replies
Sep 18, 2009
My problem is this (apologies if this is a little long ... hang in there):I can define a function in VB.NET with optional parameters that wraps a SQL procedure:
Sub Test(OptionalByVal Arg1 As Integer _
Optional ByVal Arg2 As Integer _
Optional ByVal Arg3 As Integer
[code].....
View 7 Replies
Jan 18, 2010
How can I create a nullable numeric optional parameter in VB.NET?
View 3 Replies
Mar 9, 2011
I want to have a "template" function that can receive different parameter and a type parameter, like:[code]But Vb told me that tupeList is not defined... is there a way I can do that?
View 2 Replies
Dec 20, 2011
I am using Stanav's PdfManipulation2.AddImageToPage(..., Pages) for iTextSharp library (v5.1.3) and was not able to add the image to specific pages: e.g. to add to only page 1 and 3 of a five pages PDF
Dim Pages() As Integer
Pages = New Integer() {1, 3}
PdfManipulation2.AddImageToPage(..., Pages)
Calling AddImageToPage() with the the optional Pages parameter will add the image to all pages though.
View 14 Replies
Sep 7, 2010
I want to specify an List(Of String) as an Optional function argument. But i am unable to initialize it in the function declaration.
View 1 Replies
Jun 7, 2011
I have a storedproc accepts parameters in XMLtype as
CREATE OR REPLACE PROCEDURE GetDetails(
p_para IN XMLTYPE,
[code].....
View 1 Replies
Nov 19, 2010
i am getting all filenames from a directory.parsing out the directory names & the .vb extension then converting those filesnames to classes.Every file in the LPCriteria direcotry is its own class with a "Evaluate" function.[code]
View 1 Replies
Apr 12, 2010
I have implemented inheritance for two parent classes called Table and Field. Each parent class has several child classes. In the Table parent class, I created a method that expects parameter List(Of Field).
I get an error when trying to pass in parameter List(Of ChildField) to the method that expects a parameter of List(Of Field). The error message is as below:
Value of type
'System.Collections.Generic.List(Of
com.hlb.icisbatch.data.ChildField)'
[Code]....
View 2 Replies
Jun 11, 2012
I need to create a function which have either 1 parameter with a string as data type or 2 parameters with double as data type.Something like the substring method.
View 2 Replies
Jan 20, 2011
If I create a list for a TextBox:
[Code]....
I am able to only add controls that are of type TextBox. My question to you is, can I create a List to hold more than one control type or do I have to create a list for each control type?
View 8 Replies
Feb 26, 2012
For each column in data table i want to add parameter with same data type as column data type. But looks it's not that simple.
Dim cmd As New SqlCommand
Dim dType As New System.Data.SqlDbType
For Each cl As DataColumn In DataTable1.Columns
[CODE]...
How can I do this?
View 4 Replies
Sep 12, 2011
I have a question about ASP.Net, visual basic I have 2 LINQ query's, the first one works, the second one doesnt, produces a
"Unable to cast object of type 'System.Data.Objects.ObjectQuery'1[SelmaV2.Products]' to type 'System.Collections.Generic.List'1[System.String]'.
[Code]....
View 1 Replies
Aug 13, 2011
I'm trying to code a class of RandomNumber. One of the class methods needs to populate a "List (Of RandomNumber)" ... which was passed as a parameter to the method ... with 10 random numbers between 1 and 50. DEAD SIMPLE :)
View 6 Replies
Apr 8, 2009
This is kind of two questions (one more specific than the other).If I have a method like this:[code]Can I qualify Foo against another type (for instance can I require that Foo be a String that also implements IInterface?).I'm imagining something vaguely similar to this:[code]Additionally, is there any way to qualify the Type parameter?For instance, can I require that the Type I take as a parameter is of a particular class tree?I should mention that I am using this in the context of a property of an attribute so the class declaration itself cannot be generic (this is purely focused on qualifying a method parameter rather than typing a class and its methods).
View 3 Replies
Mar 19, 2012
I did create a XDateTime class that is able to handle inaccurate date and time. This class has all the CType operators required to convert to and from a string and it has been fully tested during the last months.
[Code]...
View 1 Replies
Mar 7, 2010
I've searched for an answer and found some c#-examples, but could not get this running in vb.net:
I thought of something like the following[code]...
I know, I can create a new instance with the Activator.Create... methods, but how to create an array of this type or just declare a new variable?
View 3 Replies
Jan 4, 2011
I'm trying to create a function to parse out all values in a multidimensional Array with all but one dimension given. The details are not relevant, but for this function I need to return an one-dimensional Array containing values of the same type the original multidimensional Array has.To pass any Array with any dimension to my function, I declared the type of this parameter as Array. However, how would I create a new Array of that specific type (e.g. Integer)?Currently I have the following code:
Function GetRow(ByVal arr As Array) As Array
Dim result As (...) 'This should be Integer() if arr contains Integers, etc.
Return result
[code].....
View 1 Replies