Passing A Variable To A Sub Procedure By Reference?
Oct 20, 2009
passing a variable to a sub procedure by reference. Not sure I understand how it works. Here is the code.
Private Sub bntcompute_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bntcompute.Click
Dim x, y As Double
Is the newly modified variable actually being Passed back? and If so where in the statement is it passed back. is it being passed back to the call getnumbers or is it passed back to the statement displaysum?
In a tic tac toe game I am making there are two blocks of code that are identical except that they access different arrays:[code]Arrays plyrTaken and plyrPairs are used in the first block and cmptrTaken and cmptrPairs are used in the second. Is it possible to wrap these blocks into one Sub Procedure passing the different arrays when the procedure is called?
project, but have decided to take another direction on it, after much and continued struggling.I started out trying to use data binding, but was advised to use straight SQL statements in the code. So what I'm trying to do now: I have 2 forms, frm1 and frm2. frm1 has a combobox, which is showing all the data fine from a table, and an OK button. Upon clicking on this button, I need frm2 to load, correctly populating its textboxes and comboboxes with the corresponding data, based on the selection made on frm1. This is what I have so far:
I need to write a procedure which will allow me to set readonly attributes for certain objects, for example:My form contains two text boxes box1, box2.My sub procecdure will contain code which sets box1.readonly() = true, but i dont want to name the "box1" in the sub procedure but pass it as a parameter....I thought this could be achieved using :
private sub disableobject(byval inobject as system.object) inobject.readonly() = true end sub
I am trying to complete a homework and seem to get stuck at the last point of passing arrays and avriables to a sub to do the calculations to produce the desired result of sales tax but can;t seem to accomplish that so far.
This may not be the place to ask this, if not, you can move this post to the SQL forum but I have an application that I'm building which pulls dates from a database. The start value is stored as payPeriodStart date and I add 7 days to get the end date. What I need to know is, is it possible to store those values and pass them to a Stored Procedure? Currently my stored procedures have "static" dates in them ie:
where dateadd (n, Timestamp, '12/31/1899') - ([LoggedIn]/1000)/60/1440+1 Between '10/3/2010' and '10/10/2010'
I have an application that I'm building which pulls dates from a database. The start value is stored as payPeriodStart date and I add 7 days to get the end date. What I need to know is, is it possible to store those values and pass them to a Stored Procedure? Currently my stored procedures have "static" dates in them ie:
I am struggling with trying to pass values to a stored procedure, I am creating new records on my table by the values are not passing to the table.Here is my persistance class.
Public Function createDMRIssue(ByVal ItemNumber As String, ByVal IssueStatus As String, _ ByVal ProblemDescription As String, ByVal p_AuditResults As String, _ ByVal DMRDate As String, ByVal p_IssueCategory As String, _ ByVal p_DMRInitiator As String, ByVal p_QtyUnacceptable As Integer, _ ByVal p_ProductType As String, ByVal p_OrderNumberm_dmrissue As String) Me.Connection()
I have an application that I'm building which pulls dates from a database. The start value is stored as payPeriodStart date and I add 7 days to get the end date. What I need to know is, is it possible to store those values and pass them to a Stored Procedure? Currently my stored procedures have "static" dates in them i.e.: where dateadd (n, Timestamp, '12/31/1899') - ([LoggedIn]/1000)/60/1440+1 Between '10/3/2010' and '10/10/2010'
Here is my code for the form that will be passing the variables payPeriodStartDate and payPeriodEndDate to the stored procedure: Code: Private Sub Button1_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles startpayrollButton.Click Dim ssql As String = "select MAX(payrolldate) AS [payrolldate], " & _ "dateadd(dd, ((datediff(dd, '17530107', MAX(payrolldate))/7)*7)+7, '17530107') AS [Sunday]" & _ "from dbo.payroll" & _ [Code] .....
And lastly since I'm calling those variables payPeriodStartDate and payPeriodEndDate, I assume that my sql query will have to change as follows: where dateadd (n, Timestamp, '12/31/1899') - ([LoggedIn]/1000)/60/1440+1 Between payPeriodStartDate and payPeriodEndDate Is that correct?
I would like to create a stored procedure that will call any webservice by passing to the stored procedure the webservice name/url and its parameters. I would like this instead of adding web refference each webservice one by one.
I have three items in my checkbox list, what I want to do is for the user to select either one of them in any combination and pass these values to my sql server stored procedure which then returns data according to the values passed to it in the where clause and binds this data to a gridview. However, at the moment in my sp I have three I parameters, in the case of the user selecting one item from the list not enough arguments will have been passed to the procedure. I'm not sure how to go about doing this
I have the following code passing a dataView variable to a function and I am getting the following warning:"Variable 'cl' is passed by reference before it has been assigned a value. A null reference exception could result at runtime."
Function Editclass() Dim cl As DataView Bindclass (SqlConnection2, cl)
my issue could be found simple but I'm founding it difficults in regard of dealing with array concept in oracle and vb.netI will start by showing to you a code done in oracle side1-this script should be executed in hr schema2-create a table and call it job_testas
create table job_test as select * from jobs where 1=2
I have a radgrid bound to a SqlDataSource that includes a hidden, readonly column that stores a pk. I want to pass the value bound to that column to a stored procedure for Updates but the default behavior when the column is readonly is not to pass the parameter to the sqlDataSource. My question is whether there is a way to pass that value without having to go into the code behind. Here is a snippet of my asp markup.
If I set readonly="false" on the It works fine but then the user can edit the primary key value which is not desired. I know work arounds in code behind but is there any way to do it straight in the markup?
VB Imports System.Data.SqlClient Public Class frmMain
I have three ways of adding parameters to my query commented out above. The all seem to return 1781 records (which is all of the records) and will not filter out to what the UserName variable equals which should reduce it to 32 rows.
I use a Console.WriteLine to show that the UserName is indeed my username. But it seems to not be getting passed to the query properly. I tested the Stored Procedure before even starting in on the program, so I know it functions properly. I just don't know what I'm missing from a VB.NET perspective to get the same results into my DataTable.
In a nutshell, I am selecting values from a checked box column in a grid view. After checking the boxes I have a function that concatenates each customer number into a string called @CusList to use a parameter for a stored procedure Public Function SelectCusList()
Dim CusShow As String Dim CusStr As String Dim CusList As String CusStr = ""
Public Class Form1 Public Contestant As New ContestantClass Public HighScore1 As New ContestantClass Public HighScore2 As New ContestantClass Public HighScore3 As New ContestantClass [Code] .....
The problem I'm having is the first time I take a value, it gets inserted in the right section. The second time I insert a value, it inserts it in the correct place AND updates the previous value I inserted with the new value. So apparently when I'm doing: HighScore1 = Contestant It's pointing contestant AT highscore1 rather than taking the name, company, and score from contestant and then storing it in highscore1. How I can pass that info by value rather than by reference?
I'm still working on the code in this thread [URL] and as I mentioned in that thread, I thought that passing objects around between methods would probably be bad for performance (perhaps not really noticeably at first but maybe if I did it enough then it could have an impact).
1. When you pass a reference type to a method using ByVal then what is actually 'copied' ? I understand that ByVal copies the object into the local method that you are calling where as ByRef passes a reference to the actual object so you can work with the original object. So when you have a Reference type and you pass this ByVal then does copy the entire object or does it just copy a 'reference' to the object?
2. When working with an object that relates to a 'physical' item, such as a file on disk or a network stream between two connected machines, then what happens when you pass it around between methods (this might be irrelevant depending on the answer to the first question) ? I mean if I have a NetworkStream object that represents the data stream coming from a remote computer, if I then pass that ByVal into another method then does that mean I am still working with the same data stream or a copy of it or what?
The case is that I have two comboboxes (country and state) and a simple code to populate the state combobox accordingly depending on the selected country. Ok this is simple and easy, and this code is within the country combo change event.The case is that I have more than one pairs of those comboboxes and I wouldnt like to repeat all the populate code into every country combo change event.Actually I would like to have only one function and just call it passing as parameter a reference to the combobox I want to populate. Then I could use that reference into the function.
I have a function that accepts a String by reference:Function Foo(ByRef input As String)
If I call it like this:
I want it to do something different than if I call it like this:Dim myString As String = Nothing Foo(myString) Is it possible to detect this difference in the way the method is called in VB .NET?All the logic is in the second overload, but I want to perform a different branch of logic if Nothing was passed into the function than if a variable containing Nothing was passed in.
The code below works for the class that I hard coded "XCCustomers" in my RetrieveIDandName method where I use CType. However, I would like to be able to pass in various classes and property names to get the integer and string LIST returned. For example, in my code below, I would like to also pass in "XCEmployees" to my RetrieveIDandName method. I feel so close... I was hoping someone knew how to use CType where I can pass in the class name as a string variable.
Note, all the other examples I have seen and tried fail because we are using Option Strict On which disallows late binding. That is why I need to use CType.I also studied the "Activator.CreateInstance" code examples to try to get the class reference instance by string name but I was unable to get CType to work with that.When I use obj.GetType.Name or obj.GetType.FullName in place of the "XCCustomers" in CType(obj, XCCustomers)(i)I get the error "Type 'obj.GetType.Name' is not defined" or "Type 'obj.GetType.FullName' is not defined"
I have a List(Of AddlInfo) with AddlInfo being an object. I'm trying to pass addlInfoList by reference into a function of another class:
This works if I'm not passing the reference into another class, but when I try to do this, I get the following error: Overload resolution failed because no accessible 'Sort' can be called with these arguments:
I know strings are immutable, so the minute you change a string reference's value .NET makes a brand new string on the heap. But what if you don't change the value of a string reference; rather, you simply pass it into a function ByVal -- does this operation copy the string value on the heap as well? My inclination is "no," but I'd like to confirm.
For example: Public Function IsStringHello(ByVal test As String) As Boolean Return (String.Compare(test, "Hello") = 0) End Function
Calling program: Dim myWord as String = "Blah" Dim matchesHello as Boolean = IsStringHello(myWord)
I know passing myWord by value makes a copy of the reference to "Blah", but since I have not tried to change the string itself, would it make another copy of the string on the heap?
I am using a function that is provided by the maker of an IO device that I'm using and the call for this device turns on and off the 16 ports on the IO device by sending the value true or false to the board. The call is as follows:
I have two sub procedures. Both are triggered by button clicks. The first one contains the SQL connect and the Insert statement strings. The second button I just want to show a message box containing the strings. Is there a way to use a variable from the first sub procedure?[code]
I have a variable that gets a value in a js function. I need to get its value as a double into a vb.net variable. I have tried putting the variable into a label then grabbing it from the label in vb.net as shown in the code below:
Dim SecondName As String = SecondNameTxtBox.text()Is the above statement a correct one?Here I want to assign the value of the text box into tat "SecondName".If it's wrong, please tell me the correct way to write this statement.