I'm new to VB.NET and want to parameterise the SQL Connection Strings in my VB.NET App. I've added a function to my Main Form to retrieve the App.config File like:
Imports System.Configuration
Imports System.Configuration.ConfigurationSettings
Public Class MainMenu [code]....
In my other forms when i want to reference the Connection String, i get an error saying getConnStr is not declared?
Private Sub UpdDept_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Try
myconnection = New SqlConnection(getConnStr()) <=============
Dim mycommand As New SqlCommand()
why i get this when i've declared the Function as Public?
How to give another function's returned value in LINQ.[code]but in above query I should write code to store the return value of GetObjProperty Value(p) and add obj-p and returnValue combination to the dictionary.The last line below code is wrong. but please suggest me how to correct it. My intention is, I want output collection(say dictionary) of each fruitname and its color(returned by other function call) for all the fruits which the GetFruitColor is not nothing(it can be empty or valid string).[code]In above code last line is wrong. So how to put getFruitColor in k, how to correct it to save the k value and give me output as dictionary of fruit and k value.
Why this code doesn't work? It returns an unexpected value actually total = 0. total = Cscore(TextBox1.Text) * CDbl(TextBox2.Text)
When trying this total = TextBox1.Text * TextBox2.Text It returns the expected value but I need to pass textbox1.text to the function to get the desirable value
The function is this Public Function Cscore(ByVal score As Integer) As Double Select Case score Case score = 100 Return 5.0 Case score >= 95 [Code] .....
When the AlertsSettings.xml is not present the Appsettings is assigned to nothing. The variables that follow that definition rely on the existance of that information which will normally be set by the load method. But when there is a problem and either of the variables do not get a value how do I handle that in the code that relies on those values. The Settings class deserializes an xml document and assigned values to properties.
Sub Main() Dim Appsettings As Settings = Settings.Load("AlertsSettings.xml") Dim AlertsServer As String
This should be a fairly common question, but I haven't found a straightforward answer anywhere.
If I instantiate an object within a function in VB.NET and return it, does it return it be reference or by value. IE - should I be worried about performance if I write something like this:
Public Function ret_obj_func() As big_object Dim ret_obj As New big_obj(<lots of stuff>) Return ret_obj End Function
If I call this function from somewhere else, will it instantiate the object in the ret_obj and then create a deep copy to pass back a copy to the caller, Or will it just pass back a reference?
I'm trying to establish a connection to my SqlDatabase while getting the connection string from a function. This will eventually lead to dealing with the appconfig file, but for now I'm just getting the basics established.
Imports System.Data.SqlClient Public Class Form1 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Combobox with bound rowsource, but I want to change the displaymember to a string returned by a procedure. In Access/VBA I would have a little function to build the string, then simply code the recordsource of the cbo as:
"SELECT ClientIDS, fnGetName([ClientIDS]) AS ClientName FROM tblPerson ORDER BY fnGetName([ClientIDS])".
Pretty straightforward, but I've messed around with this for hours in VS2005/VB to no avail.SELECT ClientIDS, fnGetName
I have a 2 dimensional array of groupboxes that I use to populate a form setup so the first indice is a tab number and the second is the groupbox number.The user can dynamically add tabs to the tabcontrol but I need to add and populate groupboxes to the new tabpage and I can use existing groupbox data in the array for default values.I understand I have to code a deep clone of the source groupbox as it has textboxes in it so I want to add a cloneGBox function that returns a new, populated groupbox when I pass in the x,y indices for the source groupbox in my array.
dim gbx as groupbox = cloneGBox(x,y) and code cloneGBX as public function cloneGBox (byval x as integer, byval y as integer) as groupbox
I have the code below. The code returns a string in (IntersectingPoints) for X and Y. I need X and Y values to be in single and stored in an array to deal with later.[code]...
Have seen some solutions for C# but do not know how to solve the issue in VB.NET.
Query:
Dim Query = (From t In myEntities.Bookings Where(t.Ref = Someid) Select t.People).Sum()
t.Ref field is an Int and so is t.People.
The SomeId value is the primary key of the related table. This issue is that there will not always be records in the Bookings table with a Ref value of Someid - so the query throws the following error.
I have seen others have got around this problem with catching the error, but from reading up on this and as per the error information it seems there should be a solution (in VB.NET) to cast the query or some of the fields in the query to nullable types?
Error is as follows:
The cast to value type 'Int32' failed because the materialized value is null. Either the result type's generic parameter or the query must use a nullable type.
If I instantiate an object within a function in VB.NET and return it, does it return it be reference or by value. IE - should I be worried about performance if I write something like this:
Public Function ret_obj_func() As big_object Dim ret_obj As New big_obj(<lots of stuff>) Return ret_obj End Function
If I call this function from somewhere else, will it instantiate the object in the ret_obj and then create a deep copy to pass back a copy to the caller, Or will it just pass back a reference?
I have a Class MessageIndex which holds an integer. I have a custom DataGridViewComboBoxCell which has a MessageIndex variable. If the MessageIndex is not set, the cell acts as a normal DataGridViewComboBoxCell; if the MessageIndex is set, then the GetValue and SetValue methods of the DataGridViewComboBoxCell are overridden so as to return the value of the object from its DataSource at the index of the integer stored in the MessageIndex.
As far as I can tell from stepping through the code, that actually works fine. The object returned by the GetValue function is fetched from the DataSource, based on the integer stored in the MessageIndex.
The problem is that when the DataGridView is displayed, all of the cells are blank. The values of the cells can then be set using the ComboBox dropdown, which appears to work fine.
But why are the initial selections not being displayed? As I say, as far as I can tell, the correct information is being retrieved by the GetValue function of the DataGridViewComboBoxCells when the form is initially displayed. It's just not ending up on the screen.
When I declare two datatables and fill them both from a datatable returned by a function in class, that when i filter the one it seems to filter the other aswell?
For example:
I declare the datatable and initiate my class:
Dim DatatableOne As New Datatable Dim DatatableTwo As New Datatable
Dim MyClass As New MyClass
I then call the function that returns a datatable and apply it to datatable1 and 2 Then fill two DataGrids with the table:
1) The first function (call it GetValues()) returns values in a SQL database as a list via a stored proc. One of the fields is DateTimeSubmitted. All of this data is displayed on my webpage using a repeater control. It works fine.
2) The second function (call it NiceDate()) I created to change the DateTimeSubmitted to a nice date such as "one minute ago" or "yesterday".
My problem is I have no idea which is the best part of the process to do the conversion (at point of data extraction or in pageload etc.) or in fact how to do the conversion.
I'm a new user of VB.Net. I do have doubt on accessing a user defined Function or Sub. In some place of program, I do see the term "Call" when using the Function/Sub. In some other place without "Call". But both works perfectly. May I know the difference between the two.
m using a public variable called globalquery & a global function retriveToDataGrid() it works perfectly fine under same class /form ..... but when i try to access it from a different form , it gives no error and nothing happens
Public Sub retriveDataToDataGrid() Try Dim connStr As String = "Database=shahopticals;" & _ "Data Source=localhost;" & _
I have a new solution with 5 projects inside. a data access layer, database, 2 class libraries, and the main form. These are all components that I had worked on to get to this point of combining into 1 solution. Now what I have run into is I can not the actual functions in the class libraries. I can get to the class level, but that is it. ere is a sample line of code I need to get working. Once I get this one line, the rest will be obvious: Temperature is on the main form. get for options is "Equals, GetHashCode, GetType", etc... Before this I had bult, compiled, and referenced these classes separately, and it worked fine. I know this is going to be an easy answer, I'm just not seeing it for some reason.
I have a camera for which the complete source code with header files(.h) and all libraries files(.lib) are given in VC++. Now if I want to access the function calls in the header files and in turn the functions in the library from VB.NET, I am required to write a wrapper DLL for accessing the function calls which I never did till now.
I want to make an numerical integration method with takes in an analytic function and integrate it over a specific interval. For the numerical integration procedure I want to use some procedures in nr.com. The problem is that these are programmed in C++ and they uses functors to pass a function to the integration method. How can I do this in VB 2010?
I want to initialize the function (i.e. set a=1,b=0 for function y(x)=a*x+b) and then pass the function to the integration method. Then when the integration method call the function it only calls the function with one parameter (i.e. x since a,b is already set)
What is the best way to do this in VB2010?I want to make a general integration method where I can pass any single valued function and integration limits.
I have just started using VB, and from what I have found so far it seems like the tools you have is
- to us a delegate for the function - to use a lambda expression for the function - send a pointer/adressOf - to create a function class/structure and submit this to the function
As for now I am most inclined to create a function-class. But I am not really sure how.F.ex. I make different classes for each "uniqe function" I want to integrate, but how can I pass them to the integration function when I need to specify the argument type in the integration-function-call?This seems like a basic problem which applies to many Math operations, so I think it would be very useful to clarify this.
I'm trying to undersatnd the syntax of calling a funciton and it seem confusing when I'm using a web service in ASP.net. Maybe this question should be in an ASP forum, but it is a VB question. This simple web service allows you to type in your name and it response with an alert box with you name.
My question is, How can you call a function with 2 arguments when the function is only defined for one. I understand that the second argument is actually a method that handling the respons, but how can you interchange function arguments for methods and how do you know that there are methods for
Basically in visual basic 6 I could access word tables in existing templates with the code owordactivedoc.tables(1).select() where owordactivedoc refers to the active word document and tables(1) refers to the first table in the template.Trying the same code in VB 2003 just leads to errors. Secondly how do I access bookmarks or alternatively word variables.Furthermore how do one deploy web.services. For example the current program I am building is for another computer. Simply copying the web service to Inetpubwwwroot dont work because it is not picked up by the Internet Information Services program. I have to create the web service in vb2003 on the other computer change msconfig manually. Copy and paste the existing service vb file in the created folder replacing the empty vb file.