I have created a program that creates a blank database in a users account (each user has a seperate folder when registered) by pressing a command button, i have got it to create the database but when i try to populate it with a table to go to the correct folder i get an error
Constant expression is required
the code im using for this is:
Const strConnection As String = ("Provider=Microsoft.Jet.OLEDB.4.0;" & _
[code].....
I'm trying to make following subroutine work. The problem is this part of the statement.[code]I've tried everything and can't seem to come up with a constant to use here.[code]
View 3 RepliesI need to read a named range into an array. Then if the value in the 1st position matches a static value, read the value in the second position. I've been looking into array's and this is what I think will work, however I get a compile error on the columns.count "constant expression required". Is it because in the DIM statement I'm attempting 2 things? This is a macro in Excel. The range name is Data1 and the string comparison is "AnyString". The second value will be an integer.
Sub macro1()
Dim rng As Range
Dim x As Integer
Dim y As Integer
rng = Range(Data1)
[Code] .....
If I write the following inside my class,
<DefaultValue(Guid.Empty)> _
Public Property KeyValue() As Guid
I get an error on Guid.Empty "Constant expression is required."
What I'm trying to accomplish is to get rid of this line that shows up in the Designer file,
Me.TestUserControl1.KeyValue = New System.Guid("00000000-0000-0000-0000-000000000000")
I can avoid running the property's Set code with some conditionals on the Value sent when the form instances. I was just wondering if there's a way to deal with it similar to other data types.
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]...
We are using a custom API in our project which provide an attribute for class fields/members which lets the interface to present a popup of some range values like "On/OFF" and pass the corresponding values of the choice to our code. The attribute requires a string array to know that values.We have many enumerations defined for these ranges,We are thinking to use Enum.GetValues() kind method to get a string array for this method.However, As we know the field declaration do not allow dynamic values in the declaration? so is there any other of doing same thing in efficient way.To clerify the problem i will write the examples below;
Current Working
<RangeLookUp("On:1","Off:2")> Public ASimpleRangeVariable As Integer
While I wanted to do like this or kind of
<RangeLookUp(SomeMethod())> Public ASimpleRangeVariable As Integer
Public Shared Function SomeMethod() as String()
'use Enum to get all the items as string values forexample Enum.GetValues & enu,.GetValues [code]....
Where SomeMethod suppose to return string array to be passed in the RangeLookup constructor.Which means if we change enumeration then we don't have to update the declaration.i know there are better ways to do it but due to some custom API, the ground is limited.
If I run the following code in C# then it runs fine
UInt32 a a = 0x9E3779B9
But when I run the same code in VB.Net then it gives me error "Constant expression not representable in type 'UInteger'"Dim a As UInt32 a = &H9E3779B9
I'd like to understand why one type can't be converted to another type inside a constant expression.
View 13 RepliesI am trying to assign a constant with this value:
Public Const FIRST As UInteger = (0UI - 860UI)
UInteger data type hold any value between 0 and 4,294,967,295. MSDN.
If I try this code in VB.NET I get a compiler error:
Dim Test As UInteger = &HFFFFFFFF
Error: "Constant expression not representable in type 'UInteger'.
Why I can't set 0xFFFFFFFF (4,294,967,295) to a UInteger if this type can hold this value?
I have this error "Constant expresion is required" in this code
[Code]...
I have this code:
Public Class Beryllium
Public Const AtomicNumber As Byte = 4
Public Const Symbol As String = "Be"
[Code]....
I want to make a list out of all the constants (AtomicNumber, Symbol, Name and AtomicMass). I want to make the list also a constant. When I run the code above, I get an error highlighting AtomicNumber (on line on which I commented on "This line"). I tried .ToString() and CStr() but I get errors on both. Maybe there is a different way to make these constants one string or list (must be public and have new lines)?
i changed a class variable to shared so i can access it in all instances of the class, but it caused an error. what is causing this, and how can i fix it?
Private
Shared img As Bitmap
Me
.img = bgImage
how do I overcome it? I have created a class and compiled into .dll This code
[Code]...
In the following code i get a warning at line 59:Warning 1: Access of shared member, constant member, enum member or nested type through an instance; qualifying expression will not be evaluated.and.. At line 78 I get this Warning:
Warning 2 Property 'SelectedCustomer' doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used.
The program compiles and runs well, but i cant' undesrtand the reason for these warnings. Any Idea ?
1: Public Class Form1
2:
3: 'Form level members
4: Private objCustomers As New ArrayList
[code]....
When building a class library which contains many classes, all classes uses a lot of common constants and functions, what is the best to do:
1- Declare these constants and functions as public in a module.
2- In each class declare constants and functions used by individual class as private.
The first choice is good for easy and fast implementation, but re-using a class in a different project will require importing the module to the other project.The second choice require a lot of copy/paste for code snippet but a class can be re-used in different project easily.
I have a class set up to hold values on a registration form (VB.NET, MVC), and among the properties is a Password property:
[Code]...
I got this Error. below is my code.
GenerateTheList is function.Need help
Private Sub buttGenerate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttGenerate.Click
Dim thread1 As New Thread(New ThreadStart(GenerateTheList))
thread1.Start()
End Sub
While looking in the dataset designer for a database table I am doing in visual basic 2008 I found a line for expressions under the property menu for a specific column. I need to know the code that I would put in this expression line so that this column adds up the numbers I input into three other columns and displays that number in the column. I need it to automatically calculate this for each row in the database table.
View 13 RepliesI am trying to write following expression on a datacolumn. But it results in error:Replicate('*', nLevel) + NameWhere: Replicate() is a user defined function (in a module). nLevel and Name are two other columns in same data table.
View 3 RepliesI am using Flee to build a formula builder. It works great but the only problem I'm facing is that Flee doesn't understand Generic Methods I guess. I have a function called IIf declared in the expression context I'm using. [code]How can I work around this. I mean cannot , in sense, write all possible overloads of the function of all .net primitive types. What approach should I take.
View 1 RepliesDoes vb 2010 have a 'REQUIRED" property or control that allow you to make a textbox a "required" field? I googled and saw something about required property in controls in toolbox but somehow I could not find it anywhere in my vb 2010 toolbox. Would it be easier to write it? Does anyone have sample code?
View 6 RepliesFrom this code
[Code]...
If I put New Action(AddressOf PrivateMesage), then I get the following error: Bounds can be specified only for the top-level array when initializing an array of arrays. on the following code
[Code]...
I must convert string data from a CNC that is arithmetic expression to a number that I can use in a VB application that I wrote. The following is what I get out of the cnc. [18722*65536+19377]/67108864. I need to evaluate this expression in my VB ap. The format of the string is not always the same as what I have illustrated.
View 2 RepliesHow can I convert the following code into VB.Net?
private const UInt32 temp = 0xE6359A60;
I tried the following but it doesn't work.
Public Const temp As System.UInt32 = 0xE6359A60
visual basic 2008 express
' the following lines declare the variables and constants
Dim intDiameter As Integer
Const dblPI As Double = 3.14159
Const dblAREA As Double = 140125
Dim intLabel As Integer
Private Sub PizaSliceCalculator_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code]...
I made a working program to calculate piza slices, i was told i needed to declare pi and the areas as constants. when i rewrote the program it no longer works. the result keeps coming back as 0.
I am looping through all of the forms in my app, and I am needing to get a value from the form somehow.Example, say if I have the form named "This Form" and somewhere in that form, dont know if you can use the tag property for this or not, but I need to put a word like "Tall" for an external reference to the form.[code]"How do I get another value like the forms tag or something else".
View 5 RepliesExplain or send me in the right direction.
View 2 RepliesI have strMyColor = "Red".I would like to make lblMyLabel.BackColor to be red.Without using a variable the code would be this:
lblMyLabel.BackColor=Color.Red
I tried using the variable like this: lblMyLabel.backcolor="Color." & strMyColor
But the error is that a string can't be converted to System.Draw.Color. I understand that, as the string "Color.Red" is not the same as the VB constant Color.Red.Is there a way I can construct a valid vbConstant from a string?
I mean why? I mean to organize things I often turn modules into classes where all the methods are share.But then I thought, why not organize them into namespace?But then we can't declare constant in namespace.
View 10 Replies