[[code] 1) Is this violating the phrase static classes should not have state?
2) How can I modify the functions such that they can accept any function (instead of my above situation which only works with F(TResult) and F(T, TResult). [code]
I'm currently working with a client's VB.Net code, which was developed for them by a small development shop a few years ago and which they purchased and have been maintaining and uprgrading since. This client's primary developer is out on indefinite (likely permanent) medical leave and I'm now filling in until they bring in a full timer (as I'm a contractor here). My current task is to add some functionality to a the VB.Net code they purchased. I'm finding practices and techniques in the code that absolutely baffle me and can't make the code do what I want. I'm starting to wonder if it's me and was hoping to get some thoughts on the code I've encountered.
For example: Setting a variable to accept the result of a function by calling the function with many parameters, clearing the parameters in the function, setting them to some value, calling another function with those new values, then never using the values returned by the functions. I'll add a code snippet in the first comment since this is already getting long.
I've got a little function that just changes empty and null strings to "null":
Public Function CatchString(ByVal stringValue As String) As String
If stringValue = "" Or stringValue Is Nothing Or stringValue Is DBNull.Value Then
Return "null"[code].....
I added the bit about DBNull because sometimes it gets null values from a database. This doesn't work, though, because it won't take DBNull as a parameter.I tried changing the stringValue parameter from a string to an object, but then the If statement gives this error:
Quote: Object reference not set to an instance of an object.How do I make the function accept DBNull as a parameter?
this function enables you to calculate a full arithmetic calculation , as 5*(3+2)+6 , but : it's limited with (+,-,*,/) signs . is there any way to add a support for the another signs (like : !,sin,cos,tan,root,^,log and another signs) to give the user the ability to calculate a full calculation including the other signs which cannot be calculated within the compute.datatable function ?
View 2 RepliesThis function doesn't work if I change the input argument 'pdu' from a string to an int.Would someone please help me figure out what to do here so that the checksum does not add the ascii value of the int argument but rather the actual integer value?I took out a few lines of the actual function but it adds the input argument to a packet sent out via TCP protocol.This function shows the integer value just fine in the string that gets encoded as a byte array. the checksum is wrong.!
''Public Function buildpacket(pdu As Integer) is what I want.
Public Function buildpacket(pdu As String)
Dim packet As String
[code]....
I am cleaning up some code and I have multiple classes that are 99% exactly the same. So my understanding is that my options are...
1. Create a class and all other classes inherit from it and modify it a bit
2. Create an abstract class and all classes inherit from it and modify a bit ** I took this route
3. Create an interface and all classes Implement that interface.
Here is my 'original' class below (the one that all of them look 99% identical). This class is used in an arraylist so I have a listing of all my images from a folder I have searched.
[Code]...
I'm writing a VB.NET function with a ton of overloads. I've seen that most .NET functions have parameter descriptions in IntelliSense. For example, when typing in String.Compare(, IntelliSense says Compares two specified System.String objects and returns... you get the idea. This description changes and you click through different overloaded versions of the same functions. When you start typing in something for a parameter, it describes the parameter you're currently inputting as well. Example: strA: The first string to compare..
View 5 RepliesIs there a way to view preset functions like the Int() function.
View 6 RepliesWhat I am trying to do is have a class where the functions of the same name are both instance functions and shared functions.
Public Shared Function Get...(byval xx as xx)
and
Public Function Get...
The Public Function uses a Property xx created in the constructor, whereas the Shared Function has the parameters (byval xx as xx).
Is there a way in vb.net to create a sub/function that will take as an argument some kind of pointer to another function, and allow this new sub/function to execute the passed function? What I have are 10-12 xml-rpc functions I am calling against a remote server. Each of these functions has different argument lists (one takes 1 string, another might take 3 strings and one int, etc). All of them return an object.
[Code]...
I get this error: Cannot refer to an instance member of a class from within a shared method or shared member initializer without an explicit instance of the class.
Partial Class _Default
Inherits System.Web.UI.Page
<WebMethod()> _
[Code]....
I know it has something to do with the fact that the first function is shared and the second function should probably be Public as well but I don't fully understand the reason behind it. Probably not relevant but I'm calling the web method from some javascript.
I am currently working on a project witch contains lots of functions and properties. These functions and properties are stored in the dll. If I reference to this from within my project, these functions and properties are all in the same namespace or class. (I don;t know how it is called)Example:If I type the root namespace: Functions. I get all the functions. I would like to organize them in:
Functions.Maths (All the functions involving maths)
Functions.Internet (All the functions involving the internet)
Functions.Language (All the functions involving languages)
I tried using classes but I cant access the properties when they are stored in a class. I don't know why.
I am trying to clean up my code a bit.
I made the following function:
Public Sub sqlUpdate(ByVal table As String, ByVal column As String, ByVal var1 As String, ByVal column1 As String, ByVal var2 As String)
Public CN As New MySqlConnection
Public cmd As New MySqlCommand
[CODE]...
Which is fine, if I want to use mysql update all I have to do is call something like: sqlUpdate("test", "test", 0, "test", test) I was wondering if I could do the same with the SELECT statement and make a function. I cant think of a way to do it though...
sqlConnect()
Dim cmd As New MySqlCommand
With cmd
.CommandText = "SELECT * FROM users WHERE username=""" & lblAccountName.Text & """"
[CODE]...
The data I would want to extract would be different every time.
I have a midterm project where we must replicate what our teacher has made, it is a convenience store program. I am having trouble calling the functions, he wants us to use these:
PopulateItems => Populate Items listbox based on the category selected
GetItemPrice => Retrieve the price for a given item
GetItemPriceFromPurchases => Retrieve the item price from the purchases list box (optional. You may not need
[CODE]...
So far I have the first list box populated when the form loads. However outside of that I do not know where to call the function in order to populate the second list box upon selection of the first.
If I have two threads both calling a normal function at the same that appends strings, sometime the output string is a combination from both threads as the function had not finished executing the code before it was called again... Would a shared function wait to finish first?
View 9 Replies1) Is it possible to access the Excel mathematical functions without actually opening Excel?
I was thinking of through a DLL WinAPI call or maybe a delegate function or smaller program?
2) Does anyone know of a MS link or area that gives instruction on "how to" use every function of every Windows DLL at all?
Or for all those that Microsoft have chosen to document online at least.
One to accept only file word and pdf file and the other to accept only images(.jg|.bmp|.png|.gif)
View 1 RepliesI want the Function to accept List(Of String), Array & String and similarly return List(Of String), Array & String respectively. The Function simply adds a string (month) to the input collection. I just want to use it for string, array and list with needing to think of conversions.
[Code]...
While converting types, I have found myself using both VB functions and BCL Convert.To* methods.
E.g.)
Cstr() vs. Convert.ToString()
CInt() vs. Convert.ToInt32()
CDbl() vs. Convert.ToInt64()
etc...
Are there any subtle differences that should be noted?
Is there a way to see exactly what the functions are doing. What i mean is there a way to see the class? I know what it does, i just want to know the code.
For example the function: Membership.FindUsersByName()
I'm redoing a program for my company and my boss wanted me to created the entire thing through functions...
For the task I wanted to know is it possible to have functions within functions?
Sort of like in C where we would have nested structures?
Its a FILE I/O, with robot commands, moves and verifications....
So I would find the line in an excel spreadsheet where it moves, the coordinate, put it into an array.
Take the actual results store them into a two dimensional array...etc, etc....
Another function would eventually compare the results with the moves, and within a tolerance.
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
Here's my call:
<script type="text/javascript">
function HelloWorld()
{
var yourName = $get('txtYourName').value;
[CODE]...
In order to return a value from a VB.NET function one can assign a value to the "Functions Name" or use "return value." I sometimes see these inter-mixed in the same function. Personally, I prefer the return. My question is, what is the internal difference, if any, between the two?
View 5 RepliesI've tried everything here, but the Amazon Load Balancer API just will not accept my signature.
Whatever I try, I get a "403 SignatureDoesNotMatch" response. I'm probably missing something obvious, but having spent hours trying to figure out what that is, I'm at the end of my tether.
Here's my code:
Public Sub DeregisterInstanceFromLoadBalance(ByVal strServerID As String)
Dim strURL As String
strURL = "http://elasticloadbalancing.amazonaws.com/?"
[Code].....
I have a VBA script that connects to a site.On that site, it puts in criteria to filter on a database. It then submits it.A pop up window appears asking to Open / Save / Cancel. I don't know how to interact with that window.It is possible to Save, and specify the download location without having to use Sendkeys?Note: There is no file to directly download. You have to run the report and it kicks back the file.I know this is VBA, but I think VB.NET has probably has the same result.
View 1 Repliesi have a Function in my Component(DAL), the Function Accept an input from textbox and return a dataset.
Public Function Search_lis(ByVal lis_key As Integer) As Dssearchlis
dasearchlis.SelectCommand.Parameters.Add(lis_key)
dasearchlis.Fill(Dssearchlis)
[code]....
I'm searching for a way to validate (or bypass validation for) self-signed SSL certificates using VB .Net. I found code to do this in C# and tried converting it into VB code, but I'm not having any luck.
Here is the C# code. Here is what I tried:
Imports System
Imports System.Net
Imports System.Security.Cryptography.X509Certificates
[Code]...
I have a textbox where I have already put the keypress code to accept characters and number
View 1 RepliesI am developing a s/w. I am trying to update data in table. While I save the data, it will update into table. I have a gridview which binds table data through dataset. While I update the changes it is not reflecting in the grid view.
What I will do inorder to update the changes into gridview.