I got this in my SQL statement. I "BOLDED" the problem.SELECT OrderID, CustomerID, EmployeeID, OrderDate, RequiredDate, ShippedDate, ShipVia, Freight, ShipName, ShipAddressShipCity, ShipRegion, ShipPostalCode, ShipCountry FROM Orders WHERE CustomerID =@CustomerID
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I got this in my SQL statement. I "BOLDED" the problem.
SELECT OrderID, CustomerID, EmployeeID, OrderDate, RequiredDate, ShippedDate, ShipVia, Freight, ShipName, ShipAddress, ShipCity, ShipRegion, ShipPostalCode, ShipCountry FROM Orders
[code]......
I have a "if This > That then" statement, that doesn't seem to work, as it triggers regardless that "This" is smaller than "that". Does it matter that these variables are marked as strings vs integers?
View 8 Replies[code]How do I use variables in a SQL statement?
View 20 RepliesI have a simple table in an access database that I'm using in a VS2010 project. I have a combobox control that a user can select the horse power of a motor. I then take that selected value from the control and copy it to a string variable called gstrSelectedHP. All I want to do is run a query that will pull up the full load amps of that horse power motor from the table. I have the query already, but I need to somehow put the gstrSelectedHP in the WHERE part of the query so that it only returns that value.
View 14 Replieswith the following code example:
T04Command04 = New SqlCeCommand("Update GameResults Set CN01=@T04Var02 Where Counter=@T04Var03", T04Database01)
T04Command04.Parameters.AddWithValue("@T04Var02", T04N01)
T04Command03.Parameters.Add("@T04Var03", T04ClnRec01)
T04Command04.ExecuteNonQuery()
I am trying to use two different variables in this SqlCeCommand series, to (1) update only a particular record in the database (2) with a particular variable value. However, I get the following error:
"An SqlCeParameter with ParameterName 't04var03' is not contained by this SqlCeParameterCollection."
Dim gg = From gs In AllData_TableList Order By gs.Biology Descending, gs.ChemistryDescending, gs.English Descending, gs.Frensh DescendingAll I need is to make this Statement order Dynamically like this
Dim Variable1 as string=Biology
Dim Variable2 as string=Chemistry
Dim Variable3 as string=English
[code].....
I have a listbox that is dynamically filled by certain values depending on what table has been selected from another list box. Once a value is selected, it is being graphed vs a date & time range. With my ignorance of linq: depending on what value is selected, the linq to sql statement I need to create to grab data from my database is different as I can't use an index on an anonymous type.
result = From t In db.APS _
Where t.DateTime >= startDate And _
t.DateTime <= finishDate And t.Weight = weight _
Select t.DateTime, t.TotalConcentration
t.TotalConcentration should be selected if my listbox value is "Total Concentration", but if it's something else, like "Temperature" or "Flow Rate" (connected to appropreate database columns) - this method obviously isn't going to work. I need to be able to dynamically select a specific column from the anonymous type list, or use some other method I'm unaware of to do this.
While measuring the select case performance I encounter a strange behavior of Select Case statement with the constant expression. I don't understand why its behavior is dependent on the values to be compared.
[Code]...
My stored procedure:
[Code]...
So my idea is to have (in my VB.net project) a string that could dynamically change the stored procedure "Future"
I am using an INSERT INTO ... VALUES statement in the following matter to insert data into a new row of a database:
[Code]...
How can I substitute variables for the explicit values of X and Y in this statement (for example, variables XName, XAddress supplied by user input via text box)?
Last year (2010) I came across a FANTASTIC command that allowed me to take a string of variables with a common delimiter and break it all back out into separate variables (possibly an array) with one statement.
[Code]...
As long as the delimiter was a unique specifiable character, this one-statement command could break it out into elements. my memory and point me in the right direction.
I have code, shown below, that works all except for 1 thing: The variables being passed byRef get passed, but once modified in the else section of the "if me.invokerequired" code of RecordData, the variables are never updated in the calling function. To reiterate, the calling function does not receive the updated data that is in the variables custid and amt.When debugging, I see the data change in the else section of "if me.invokerequired", but once it returns from the callback the data is missing.[code]
View 15 RepliesI define some global variables of a class as follows:
Private Class MyClass
Private var1 as Decimal
Private list1 as List(Of string)[code].....
But I found that after this form is closed, all above variables, var1, list1, list2 still exist in memory. I thought they should be collected by gc since the form is already disposed as I confirmed.
Add: I have monitored half an hour after the form is closed. But these variables are not collected by gc. I have an automatic update procedure on the form which uses above variables.Since the above variables still hold values, the automatic update procedure is always called which causes exception. (One quick fix is to check if form.isDisposed in update procedure. But I do not think this is elegeant. Besides, these variables occupy memory.)
Does the memory used in declaring variables are reclaimed by the OS when these variables go out of scope?Does the memory used be released by setting thier value to nothing? if not, then how can I force the garbage collector to run or excecute at a certain/desired time..How about in Windows Forms..How can we make sure that the memory used in initializing and showing forms be released if those forms were closed?
View 13 RepliesQuestion 1: What is the difference between "Background Worker" and "Worker Pool" as indicated within the MSDN samples provided.
Question 2: I noticed while using, AddressOf _Function_, variables cannot be passed; what would be an efficient solution to this?
Question 3: While using multithreading is it required to invoke before setting variables, or only form properties?
Question 4: While using System.Net.Sockets is it safe/efficient to use Application.DoEvents while waiting for new data; or would be using a Do While loop be fine without DoEvents since the action would be multithreaded? Note: there can be up to 2000-3000 sockets in use at a time.
I'm new in .NET programming.I have a class Form1 that includes Button1_Click event.Button1_Click creates a multiple Text Boxies at run time)Here is the class:
Public Class Form1
Dim shiftDown As Integer
Dim counter As Integer
[code].....
How do I access the resources I created in the Tools/Properties/Resoruces section? I can't remember how to do this?
View 3 RepliesI have a class that does four things: unzips and zips files, downloads and uploads files. It needs to complete all four actions for 9 different command line apps. Which means, unfortunately, that there needs to be 4 different strings for each time. All in all, I need to create 36 strings which are different command line arguments. I need to figure out the best way to accomplish this. Should I just create all 36 strings in the class? Or should I use a constructor? Or... properties? Maybe a structure?
View 1 RepliesI have this little code here in vb 2008, I created a flag var to see if the user has clicked the button "enter" so the flag would be set to true. If its true then the game would begin...
I have a label that says "Press enter to Play", and if the user presses play the flag is true, the label visible is set to false. I have the keydown event to check if the enter button has been pressed, i checked if it works and it does, but the var of the flag is always false in my other subs...
Thats the thing with vb i dont understand is when you make a public variable, and when you change the value of the var in a sub, it doesnt change globally.
CODE:
I am making a program where in form 1, the user inputs data, and the data is used in form 2.[code]There are 12 number boxes and 12 text boxes. I also tried to use a label (label 4) to test if i could even use the variables on form 1. I can't. When you press the button, It clears the text box, and removes the label.
View 6 RepliesI'm trying to get a handle on creating my own Interfaces for a project I'm working on. I know the MSDN help shows that all member signatures will become Public when implmented, etc, etc. However, if I implement the IDisposable interface provided by the framework, comments and private members and fields show up! Not only that, but some of the methods have comments and code within!
How did they do that? And can comments, private fields and members, and predetermined code be declared as part of an interface by the average developer?
I have a piece of code that returns no error but doesn't do what I expected. I want it to "select" a label then assign it a new .text value from a DB
[Code]...
the datagridview seems more complicated the I thought it would be my problem is: how can I if I added three columns to my datagridview, let the program insert something with 2 variables and in the last column i would have to do some calculations with the column2 (like the sum of all rows in column2)
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I have several classes that use a bunch of strings for directories, arguments, etc.
At the moment, they're all just declared globally within the class like so:
VB.NET
Private str1 As String = "path"
Private str2 As String = "path2"
Private str3 As String = "arg"
To me, that looks awful and doesn't seem like the proper way of doing things. So, I was thinking, should I make a property for each string and then use a constructor to initialize them?
Would that make a difference at all? Is that the proper way of doing things?Also, some strings are used in a ton of different places and they're basically just being copied from one class and pasted into another. So, do you think I should do what I suggested above, but with a class whose sole purpose is to house those strings so that the code isn't duplicated a million times everywhere? Would that be the most efficient way of doing things?
[Code]...
vb
For X = 1 To 3
AddHandler LabelX.Click, AddressOf Action_Command
Next
[Code]....
code snippets adapted to show the correct way of going about with this and perhaps explanations of the underlying concepts also.
How can i make variables stay true even after i close my program so on next run there still true?Heres the Code i am using to set the variable (if it helps) :
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim Activated As Boolean
If Activated = True Then
[code]....
BTW this is to check if the product has been activated or not.
I have 10 variables, how do I save it into a txt file with each variable a line?
View 9 RepliesI have a txt file and what to read it in a variable in vb.netSo for example :
txt file contains:
Name=Tom
Code=23423
[code]......
I am creating 2 forms (btw these is test script just to learn and understand it.) 1 form is where the info comes from like the Username and other stuff the second form is where the data will be shown.. i got it to transfer the data to second form but what im having problem with is well more of a question is how can i send the variable to a statusbar?
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