Assign A Number To A Single Variable It Does Not Equal The Same Value?
Nov 2, 2010
I have been searching the internet trying to understand in its simplist form why this behavior happens.
Dim mysingle As Single = 456.11 Dim mybool As Boolean = mysingle = 456.11
In the lines above mybool becomes false. I found this behavior when putting the single into a double I found extra digits showing. The .net documentations states a single is an approimate value I gatehr a single is a 32bit floating point number? But why are extra digits appearing when I have explicitly said what the number is.. surely the memory should store that numbers either side of my number are 0 to fill up the memory location?
I have a problem with a sql query. Through the query I am trying to search database for any occurrences of string (can be anything) in a column using the SQL LIKE command. The problem is that it works fine for most of the strings say john, jim, ji"m , but does not work when i include the following characters which are ( ' , { , } , and a single quotation mark). MYSQL query takes care of these special cases by putting them in [] block whenever user enters them .But i am getting the following error when i go to query the database using the GetSelectCommand() in VB.NET
Exception Details: System.ApplicationException: Number of values provided must be equal to the number of placeholders in query.I have checked the query over and over again .. but its fine .My database server is Sql Server 2008.So my application throws the exception in this command:
Using reader As MustDisposeDataReader = _ pmSystem.DatabaseManager.GetSelectCommand(selectStatementBuilder.ToString(), New Object() {})
Where MustDisposeDataReader is an instance of a class in an internally developed library, which inherits from System.Object. pmSystem is an instance of the class PlanManagerSystem which implements the commandlayer. GetSelectCommand() takes the select command
How do I declare/define a ResourceManager in the following code so it doesn't equal Nothing when it reaches rm.GetString("Magnitude") in the following code? My.Settings.. is returning a valid string.
I have 10 checkboxes on my screen. I have a variable setup called "case" as a string. I want to know how I can say: If checkbox1 is checked then case would be equal to "this". If checkbox2 is checked then case would = "that" Example of something I tried to cook up but didn't work because it tells me that I can't only use this in a "select case".
Dim Case as string If checkbox1.checked = true case = test1 end if If checkbox2.checked = true [Code] ......
i am using a c++ dll to control a usb device. a while back i created a vb6 program that interfaced with the dll.it worked perfectly.now i am trying to make one in vs2008.here is the header of the function i am trying to use in teh c++ dll [code]but this get no value for textbuffer.and after the function is called a few times it gives me a memory error. i think it is because the string is not fixed length.is there a way i can get this to work in vb.net without rewriting the dll
The title is to make this easy to find for others having this error. I'm new to Threading, so this is really giving me heck. I'm getting this runtime error that crashed Cassini. This is code that I'm maintaining originally developed as a website project in VS 2003 and converted to a VS 2008 website project.
For Each product As String In products If Not product.Trim().ToUpper().EndsWith("OBSOLETE") Then calls += 1
Public Partial Class WebForm1 Inherits System.Web.UI.Page Public num1 As Double[code]...
This is a part of a calculator code. When you press the button "BtnAdd" the text in TxtRes is held by the global variable "num1" and the operation number (whether add or subtract) by "oper". My problem is : OUTPUT 1: prints num1 = 25 (for example)While OUTPUT 2: prints num1=0
Why is this happening ? Isn't the value of num1 supposed to be equal everywhere in the form at a given moment ?
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.
I have a form that I am adding a set of buttons to. I am adding an event to those buttons. I need this event to function slightly to determine what button was pressed.
I need the button to simply set a string variable equal to the clicked buttons text so I can determine what button was pressed.
How can this be accomplished?
''Adding the buttons'' For Each dr In dtMenus Dim strMenuName As String strMenuName = dr.Item("strMenuName").ToString
I've been making this BlackJack program for a school project
I have 52 image files, labelled from '_1' to '_52' in my resources folder, each number corresponds to a card.
My question is, how do I get a picture box to assign the correct resource according to a variable
So, say I have
"pictDealerCard1" -> picture box which displays the first of the dealers card DealerCard1 = 37 -> random number generated through INT(RND() * 52) and resource '_37'
I need to assign a varible in a while clause. I.e., i would do it in php like this: while (!is_bool($char=$this->getChar()) in every loop, the function would assign $char a value, the is_bool function would test it, and the code INSIDE the while clause would have access to that $char.
i would like to assign the value of a combobox to a variable and use this variable as a parameter on the insert statement.see code below,code 1 works ok,but code 2 brings an error relating to wrong datatype,i cant seem to find where the problem because i think i am doing everything right.
[Code]......
i would like code 2 to work so that i can assign the variables different values at different scenarios. column serialno is a foreign key from table Stock.
I want to assign a string value to a variable in the DataGridView LostFocus event. I found that I can't just do variable = "string value, it will give me the "Unable to cast object of type 'system.eventargs' to type 'system.windows.forms.datagridviewcelleventargs'" error.
The function created by double-clicking on the datagridview is:
Private Sub DataGridViewInvoice_LostFocus(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridViewInvoice.LostFocus
I'm trying to retrieve data from an access database, but I'm trying to do it all in VB. Basically I need to query the database, and I think I've done that correctly. But then I need to assign the value in a certain field, to a variable. So for example, Dim email = orders.CustomerEmail. How to assign a value to a variable.
Below is my current code: Dim acc As New AccessDataSource() accDS.SelectCommand = "SELECT TOP 1 orders.OrderDate, orders.OrderNumber, orders.OrderProduct, orders.OrderTotal, orders.CustomerName, orders.CustomerPostCode, orders.CustomerEmail" accDS.DataFile = "~/App_Data/Database.mdb"
I get nothing but headaches when I try to update settings in the My.Settings class, or when I try to assign a newly assigned setting to a variable. Sometimes the settings update OK at run time; other times times they update only after the application closes; and other times still they appear to update at run-time, then when I close the program and reopen- they go back to the previous settings.This is how I assign a value to a my settings and how I assign a setting value to a variable.[code]
Dim code As String code= " <meta http-equiv="Content-Type" content="text/html; charset=windows-1254"> "
i think i am getting this error because of double Quotation marks "character constant must contain exactly one character."how can i assign it to a string?
I think I remember reading somewhere that it was possible to assign items to a variable if the item inherited from a base class, but I can't remember how.
I want to have a class that gets properties set and one of the properties is an error code property. I want to assign any exceptions that occur to the property, but it could be any type of exception. I remember that all exceptions inherit from the Exception class.
How can I assign an exception to a property based on the class it inherits from?
Any way to attempt to assign a variable within a data class or structure when I have the variable name as a string. Where would this be useful? Let's say I have a data class that exactly mirrors the columns of a table in a SQL database. This lets programmers easily interact with table row data as it gets passed around as an actual, specific object since Intellisense can enumerate the variables for them, etc.
However, populating such an object is tedious and repetitive--the programmer who creates the new object has to one by one match up all the members when reading from the SQL data adapter. It would be nice if they could somehow enumerate all the variables in that class and attempt to auto-assign the values from the database instead of having to build a custom population method for each new data class. A person could create a hash table or tree or something that pairs member names with actual objects.
I'm wondering if it is a typo. Do they actually really wanted to say: the implementation of the JVM is free to instead of the compiler is free to.
and my second question is that do we have this issue with C#/VB as well? (in which the ""compiler"" is free to assign a value to a variable even before the variable is fully initiated/even before the constructor function of the class of the variable is fully ran.
