I need the create a function with two variables Price1 and Price2 and the following rule:
if Price1 > Price2 at time t and not (Price1>Price2) at time t-1 Then
result=true
else
result=false
I should be able to use a loop to store the time t and t-1 Price1 and Price2 values.How can I do this in VB.net
I have one test class which having few variables declared in the header of the class where it will be accessed for all the subroutines and functions in the class. Here's the sample of my declaration:
Private m_dblMaxPwrLimit As Double
Private m_dblMaxPower As Double
Private m_intHalfPwrIndex As Short
Private m_intMaxPwrIndex As Short
After that, I have one Private Function which need to access some of the variables declare in above. Part of my function is show as below:
Private Function GetPmaxIndex(ByVal Serial As Short) As Boolean
Dim i As Short
Dim Total As Short
[code]....
The problem is when I step into the line of m_dblMaxPower and m_intMaxPwrIndex, I can't see the value of these variables which is suppose I can see it as in VB6. Additionally, when I put Add Watch for these variables, it showed 'unable to evaluate expression'. I guess it is not being used and I think something is wrong with my declaration but I do not how should I declare it corretly because as for VB6, we can declare all the variables in the header of the class and we can use it for all the subroutine/function within the class.
How can I use the Evaluate function in VB.net in Visual Studio 2008 so that to evaluate a string which consist of 2 variables to be evaluated.[code]...
View 2 RepliesI am using a two-dimensional array of 10 elements, but my code is extremely slow.
[code]...
I create a new empty array with every iteration of the for loop. Is there a way I can use the same array but just clear it instead?
How to declare two object in one statement for vb.net?
Example
If IsNumeric(TextBox1.Text),(TextBox2.Text) Then
lbl_answer.Text = Val(TextBox1.Text) + Val(TextBox2.Text)
Else
MsgBox("Error only number can be calculate")
End If
I can do
if isnumeric(textbox1.text) then
But I can't say
if isnumeric(textbox1.text), (textbox2.text)
How can I do so?
Description of Program/Events. I would like to come up with a number generator that takes the Total number (for this example I'll say 20), divides it by 2, and does alternating additions so the end result will generate a list like this:
1, 11, 2, 12, 3, 13, 4, 14, 5, 15, 6, 16, 7, 17, 8, 18, 9, 19, 10, 20.
I can understand the arithmetic, just can't work out how to express this in code. The end result would be save in a .Txt file (I have added a SaveFileDialog1 control, but figure I need to get the result before I work on the export).
Dim StartValue As Integer
Dim EndValue As Integer
Dim TotalValue As Integer
' Convert input to numeric variables.
StartValue = Val(StartNumTextBox.Text)
[Code] .....
Why are static variables set equal to 0 in the declaration when 0 would be the default value of the numeric variable anyway when it's first declared? Not including the "=0" in the static declaration seems to work with no problem.
View 2 RepliesThe code below allows me to enter an integer in to the text boxes, but if I enter a decimal in any it throws an error. How do I validate decimal values in addition to integers?
Private Function numeric() As Boolean
'validate text boxes as numeric
Dim blnnumeric As Boolean = False
[Code]....
is there any function to validate if a string has only numerical characters? I can cross character for character and verify if it is a number. But I look for something simpler or if already a function like that exists.
I cannot use IsNumeric or IsDigit because it returns numbers to True with point or comma.
I need only numeric characters (no comma nor points
When I am writing a sub or function that does some calculations etc. I often need a loop or a integer variable to count.
An example:
''' <summary>
''' Compare elements with the new data and perform all necessary actions.
''' </summary>
[Code]....
As you can see, variables like timespan, nullCount and seconds are declared within this sub.
My question is, is it better to declare these in the class? I can imagine that would boost performance.
Is there a numeric text box, not an up-down box, a SIMPLE numeric box into which the user can place a number, 5 boxes actually, then on command have the five boxes added and the sum displayed?
View 8 RepliesI am having trouble getting server variables remotely in VB .Net I need to basically mimic this PHP Function.
function showvar($string)
{
if(isset($_SERVER[$string]))
[Code]....
Atleast show me how to return one variable.
if this is a dumb question. I don't ever have to write anything in VB.NET.But I am passing variables named "name" to a function and sometimes it may be 1 name or 2 names, etc. I want to check in the function if its only 1 name don't add a comma, if it's 2 names add a comma. Is there a way to get how many "names" there are?
EDIT: Added my ode to make my question a little more clear. sorry for not doing it before.
My Code:Public Function GenerateCSV(byval str as string, byval str1 as string, byval str2 as string, byval GrpName as string)
[Code]...
I wanted to know if u define a dimension in a function or subroutine and that func/sub is called say 5 times, does the memory new block of memory get assigned to it every time the func/sub is run or does it use the one it got assigned the first time?
View 6 RepliesI'm trying to make an application that calls a function to create a timer, but I cant use WithEvents or Private inside of a function or sub, Is there any way to do this?
View 5 RepliesI have 3 variables. Lets call it "a", "b" and "c". These 3 variables can "independently" have 3 different values. Lets say: "1", "6" and "10". when you think of them as combination; there are (3^3) 27 combinations. I am told that it can be done through the recursive functions. However i am not a good developer to handle with that. Would u please help me?
- 3 variables and 3 different values are simplified. In fact; the numbers of variables and different values can vary.
- i know only the language, visual basic in .net; please don't answer in other coding languages.
additional note: i am going to put the these combinations in the string format into a collection.. for example "1;1;1", "1;6;1", "1;6;10".. and so on..
I have the following code:
Public Function StoreFields()
Dim Lockbox, Cash_Deposit_Date, Batch_Number
Lockbox = Xdocument.DOM.selectSingleNode("dfs:myFields/dfs:dataFields/d:tbl_GC100/@Lockbox").Text
[code].....
I have tested the variables in the Functions and the are correct.
I've been looking at threading to make my webapplications more responsive. I've found out how to thread a sub that takes no variables and doesn't return anything, but I can't find out how to achieve this for a function that takes variables and returns something. here is an example
[Code]...
I am reading a data file and storing them in an array of string.Data is random, could be like "1","2","133,18" but sometimes there can be missing values like "?".Once I load the data in the array, I want to check if at least a majority (like 60% of them) are numeric values.If yes, then I wanna track down the higher and lowest value in the array, and output a range of 5.Loop through the array
If 60% of them are numbers (integers or decimals) then find highest value, find lowest value end if produce range
If for example lowest = 1 and highest = 100, range of 5 means 0,20,40,60,80,100 (so 5 ranges are 0-20, 20-40, 40-60, 60-80, 80-100).Also if the ranges turn to have decimals due to weird numbers, I would like to round them up.My problem is, in order to find highest and lowest when there are non numeric values in the array like "?", how should I handle those? I was thinking of something like Double.NaN but I would have to have an array of doubles.
I'm trying to evaluate a lastname and then set a value. so first two characters of last name btw M-MI would be M1, MJ-MZ would be M2
View 1 Repliesif i do not need to evaluate all the expressions, am i right to say that there are benefits and no disadvantages of using AndAlso compared to using And
example:
if a=b And f=g And y=k
can be better done with:
if a=b AndAlso f=g AndAlso y=k
I have this code and it evaluates to false instead of a string. All its doing is building a string.
[Code]...
This is probably a basic question, but I have never used this syntax before. Can someone tell me in detail how this expression evaluates to true? [Assuming IsOdd is a boolean type].
Dim i As Integer = 3
IsOdd = (i And 1) = 1
I am using a class to check for certain words in my application to prevent SQL Injection. In the class, there is a for loop that tries to match a specific word with the words from a blacklist. If there is a match, I must redirect to the system's error page. However, when a match is found and I try to redirect, I keep getting the error "Unable to evaluate expression."
[Code]....
So I am trying to evaluate 3 conditions in an if statement. Its not working how I would assume it should. I basically want to do this:
vb.net
If PGN = &HEF007E And PGNData(0) = &H58 And (PGNData(1) And &H40) = &H40 Then IgnOn = True Else IgnOn = False
If I write it in that manner it gives inconsistent results. If I workaround by writing it this way it works perfectly:
vb.net
If PGN = &HEF007E And PGNData(0) = &H58 Then
If (PGNData(1) And &H40) = &H40 Then IgnOn = True Else IgnOn = False
Endif
What is the proper way to do this with only one if statement?
I am looking for a way to simplify algebraic expressions in VB.NET. It is preferred if you can give me a link to a pre-written library or class.
View 1 RepliesI have functions in my program that stop after it reaches a Return line but I need the function to continue in case what I want the function to return changes. Is there a workaround for this or a way to force the function to continue after a return?
I made a Test Program to demonstrate the problem. It is a Form that contains only a button.
Here is the source code:
[Code]...
The messagebox always says "It returned False" when if it continued going through the code like I want it to it would have returned true.
I have an LLBLGen Pro project which has generated VB.Net 2.0 Self Servicing code.I have a function to return a list of custom structures based on a search using the generated code.I would like to supply a Dictionary of FieldNames and Values to this function and for each one add a new Predicate Expression to the search.How can I check the String within the dictionary that represents the Field name and work out which EntityField to add the Predciate Expression for?
Dim dbFiles As New AllFilesCollection
Dim dbFilter As New PredicateExpression
If Not String.IsNullOrEmpty(ClientName) Then
[code].....
I have this line in some
Integer.TryParse(ThisRow.Item("DatumID").ToString, n)
ThisRow is a datarow. The "DatumID" in this case happens to be an empty string, but is not Null. When I break on this line, and try to evaluate it by highlighting it and pressing Shift+F9, I get the message "Unable to evaluate expression". Interestingly, it is actually evaluating correctly (since the item holds an empty string, TryParse returns False).
I have tested this in every way I could think of (mostly I thought I had left out a parenthesis in my expression, but that wasn't true). So why won't that expression evaluate when tested, even though it is actually working correctly?
I am new to VB.NET and I keep telling myself there must be a better way to do what I need to do several times a day which is look into a list and see if that one field is set to true anywhere in that list.
So far, I've been using the For Each statement:
[Code]...
But I know some of the other languages can do something like: if ListOfPlayers(*).isActive == true
which just seems more concise and to the point.