Did anyone else read this article under Visual Basic News? I thought it was a very bad treatment of the subject. I especially don't like articles like that when the code they post relies on Option Strict Off.
According to MSDN The And operator can act as a bitwise operator OR a logical operator.The only way to know if it is used as One operator or another is, If it is on the right side of an assignment operation? for example x = 3 AND 5. I cannot find any other instances where the bitwise operator would be used instead of the logical operator, are there?
I recently installed visual studio 2010 and am using visual basic.The problem I am having is that some operators do not show up within the editor. For example the code line below test = 3 + 5 - 6 / 7 * 4
only displays
test 3 5 - 6 / 7 * 4
the = + operators are not visible although they are there since the program will work as intended....and if I open up the .vb file in notepad everything is there. It just won't display within Visual Studio.
But it is giving me this error: Operator '!' cannot be applied to operand of type 'long'ES_NUMBER is of data type long.I tried changing it to int, string, etc. All doesn't work.
The interesting thing is, that when I try to shift any number greater than int32 in .net, it yields bad results.. Every number under int32 (2147483647) yields the same results from php and c#.net or vb.net Is there a workaround for this in .net?
I want to perform a bitwise-AND operation in VB.NET, taking a Short (16-bit) variable and ANDing it with '0000000011111111' (thereby retaining only the least-significant byte / 8 least-significant bits).
I have an abstract user control(baseModule) that has a property that I plan on using a bitwise comparison on to determine what export types are supported by that module. In the designer of a module derived from baseModule, I am presented with a combobox with the ability to just select a single value (Html, Xml, etc.) I would like to be presented with a drop-down checked listbox so I could select which values I want.How can I accomplish this inside of VS2008? I've seen other properties support this.
Public Class ExportTypes Public Enum ExportType Html = 1 Xml = 2[code]......
I'm re-writing some old application in VB.NET to C# and ASP.NET 3.5. Everything is going OK but I have this problem - and, as the database will not be changed, I must find a solution to it.The old app saves the list o desired days (from Sunday to Saturday) in a byte. This is the way it do it:
If chkDaily.Checked Then daysBitmask = 127 ' This is for a full week Else
m_ArchiveBoolean, m_HiddenBoolean, m_ReadOnlyBoolean, m_IndexedBoolean, m_CompressedBoolean are all form level booleans that's set from their appropriate Checkboxes on the form before this code runs in a BackgroundWorker.
Why is it that this code works:
Try Dim fi As New FileInfo(element) With fi If m_ArchiveBoolean = False Then
[code]....
In this 2nd one attributes are being changed, but they're the wrong ones and I can't pinpoint it right off hand.
Edit: What the overall goal of this is that if the user has the attribute checkbox checked then the file needs to have it set, other wise the attribute (if it's present) needs to be unset.
I am trying to combine three Byte values to one Long value, like System.Drawing.Color.ToArgb() does.
I've looked up reference source code to find it and converted it to VB .NET:
Return CLng((CInt(red) << 16 Or CInt(green) << 8 Or blue Or CInt(alpha) << 24) And -1)
It works fine of course, but I don't really understand why alpha shifted by 24 is last, not first (so it would be in nice order 24, 16, 8). I don't really understand bitwise operations a lot. Also, this code snippet works for 4 bytes, which is redundant for me, I need just three bytes and I wonder if Long is still required when bytes are only three, wouldn't Integer do just fine in this case?
So, my question is, how do I rewrite this code to work with just 3 parameters? Do I need to use Long? And, I know this is silly, but is it possible to make byte shifting in order 16,8,0 instead of 16,8,0,24? It's really just aesthetics, but I am awful perfectionist.
I have written a simple VB.net application which saves information to an RFID tag. I am now trying to compress my data. The solution I have come up with involves bitwire operation.Basically I store 2 numbers per 1 byte (0-9, 10 being a period, 12 possibly being a negative/positive flag,13,14,15 unused as of yet).The code I am using basically shifts the byte containing a number left, 4 spaces, then 'OR's it against another number.Therefore 12 is now represented as 00010010. The problem i'm having is decompressing. Obviously getting the '1' back is easy, as I just shift right 4, then grab it. I need to append or remove the last 4 bits.My solution after many headaches was to reverse the bit order, shift left 4, then reverse, then tostring it.
m_ArchiveBoolean, m_HiddenBoolean, m_ReadOnlyBoolean, m_IndexedBoolean, m_CompressedBoolean are all form level booleans that's set from their appropriate Checkboxes on the form before this code runs in a BackgroundWorker.
Why is it that this code works: Try Dim fi As New FileInfo(element)
i'm trying to find a way to get with vb.net info regarding logical drive such as: Total Size, Free Size and Volume label ame and to write the info to some textbox or somthing similar.
Sorting arrays are useful when you want to get the first/last/min/max logical item of a list. I.E. A list that contains numbers and you want to find the Min/Max (without LINQ), you can sort the list and pull the first/last element. It's also useful to display lists to the user in alphabetical order.
I need to test a logical expression held in a string to see if it evaluate to TRUE or FALSE.(the strig is built dynamically)For example the resulting string may contain "'dog'<'cat' OR (1>4 AND 4<6)". There are no variables in the string, it will logically evaluate. It will only contain simple operators = > < >< >= <= and AND , OR and Open and Close Brackets, string constants and numbers. (converted to correct syntax && || etc.)
I currently acheive this by creating a jscipt function and compiling it into a .dll. I then reference the .dll in my VB.NET project.
class ExpressionEvaluator { function Evaluate(Expression : String) { return eval(Expression); } }
Is there a simpler method using built in .NET functions or Lamdba expressions.
I've seen the operator Max used two different ways. The following two queries produce the same results. The MSIL code is slightly different. What is the benefit of using the Aggregate operator? Logically, is there a difference?
I have the need to express simple conditionals as program input. The input must be human readable. Is XML suited for this? For example, I have the following conditional statement:
If AnimalType = Leopard And (SourceCountry = Kenya Or TargetCountry = Kenya) Then ZooKeeper=Jack Else ZooKeeper=Jill End If
Expressing the above in XML might look something like this: <If> <Conditional> <And> <AnimalType>Leopard<AnimalType> [Code] .....
How best to represent conditional statements in XML? I haven't yet explored using attributes. I don't currently have the need for nested 'If' statements or the 'Else If' clause, but I'm going to try and work them in anyway. Perhaps the VB code is more 'readable' than XML can be in this case and I should create a custom flat-file format instead.
I am listing all logical drives with GetLogicalDrives() function and i am getting that----( A: , C: , D: , K: , M:)[code]If i checks "Get FilesCount (Drive_name)" for A: (Floppy Drive) then I gets error "DRIVE NOT READY".I want CODE WITHOUT THIS ERRORRR Even if floppy drive is empty or a CD/DVD-ROM is empty.
Can I set up a change in the font color when a certain true value comes up with a logical test - e.g. If the "value_if_true" says STOP, can I have the STOP show up in a red font and if the "value_if_false" says OK, then leave it as a black font?
I want to place the arithmetic operators in an array so I can randomly select one at a time. I am not sure how to declare and initialize them so that I can use them in an equation.