I'm working with byte arrays and building and disassembling Int16/UInt16 and Int32/UInt32 from them. I'd like to not worry about the Sign bit until I return the final value and just have the code return the appropriate value for the data type that was requested to be converted to/from the byte array
View 3 RepliesI would like to know how to convert a unisgned byte to signed byte
Atm I got this
a
Function readSignedByte() As SByte
'-128/127
Dim b As SByte
[Code]....
it doesn't work one that well works for numbers positive over 127 if lets say ReadByte() has 128 it would give overflow error which I don't want it to give I would like it to overflow the number to negivate value aka its signed value.
I need to read signed and unsigned 8 bit, 16 bit and 32 bit values from a file stream which may be little-endian or big-endian (it happens to be a tiff file which carries the byte order indicator at the start).I initially started by writing my own functions to read the values and was able to do so for unsigned values. e.g.
Public Function ReadUInt32() As UInt32
Dim b(4) As Byte
input.Read(b, 0, 4)
[code]....
But then I started looking at signed values and my brain broke.As an alternative, I found the IO.BinaryReader which will let me read signed values directly but doesn't seem to have any way to indicate that the data is big-endian or little-endian.Is there a nice way of handling this? Failing that, can someone tell me how to convert multiple bytes into signed values (in both byte orders)?
I have been trying to compute the checksum for a line of hex code. This is to create a hex file which will be loaded onto an embedded micro.Some of you guys may not know how this is done so very briefly:
a line of hex bytes:
: 10 01 00 00 21 46 01 36 01 21 47 01 36 00 7E FE 09 D2 19 01 40
The underlined bytes are taken and summed. (in this case the decimal 960). and the bold is the checksum Only the 8LSB (or single least significant byte) is needed to compute the checksum... which in this case, 960 = 03C0 in hex, so only C0 is needed.Two's complement is then taken:
step 1) logical not of C0 which is
step 2) add one (integer)
BIN...........DEC...HEX
[code]....
So here is the code I have been using: (quick mention that in the string passed, the hex bytes are all grouped together, there are no space characters)
Public Sub CreateLine(ByVal Data As String)
'Dim BDataArray(DataLength) As Byte
Dim IDataArray(Data.Length) As Integer
[code]....
where i get into trouble is where i commented 'i get into trouble'. My code works, but it's rather crude Now, in that line i first convert the hex value (string) "SChecksum" into an integer. I want to NOT this, so I get my step 2 from my explanation. However, the results appears to be a signed logical NOT. which gives me the wrong answer. My hashed togther version simply subtracts 256 before the not, in order to give me the correct answer.
Basically, I would love for someone to chime in and point out the flaws in my function, and push me towards figuring out the 'proper' way of doing this. Also I can't quite wrap my head around what would happen in the case a string were passed to my function that is over 16 bits, but I imagine I would have to subtract a larger value than 256, before doing the NOT in this case?(whilst we're on the subject of functions, I've used a 'sub', in which case should I used a sub, and which case should I use a function?).
In VB .Net this code:
Dim t As UInt64
t = UInt64.MaxValue
t += 2UL
causes an overflow. It is my understanding that in C it "wraps". Assuming that is true, is there a way to mimic this in VB? I need this for an implementation of UInt128 I am trying to write.
I have query that involves a cross-language operation, namely converting 4 SBytes to a signed integer. The source language for this operation is Java, which utilizes the ByteBuffer in order to extract a signed integer from the data stream. The inner workings of ByteBuffer are at best a black box to me, as I haven't been able to find any hints to what actually goes on when Java extracts the integer. [Code]
View 2 RepliesI am working on a UDP Client/Server, and currently i have them sending back and forth strings, which i convert to bytes, and then open the bytes to read. I want to now send an Object instead of those strings, which includes multiple unsigned integers and strings.
View 39 RepliesOkay, so I have to convert letters to numbers, each letter in the alphabet is assigned a value that I've assigned. But I need to run through a textbox letter by letter, and convert that letter to the numbers that I have, and append. So if I had a textbox with "JANE", it would output 942383312318265498643 assuming that the following letter values were true
A - 833123
B - 2277765
C - 33935654
[code].....
using Visual Web Dev 2008 Express and i am having an error when converting a set of integers to string. see code below. I cannot work out what it is that i am typing incorrectly. For ref, i return ten 0's as the result.
Dim numbers(9) As Integer
For i As Integer = 0 To numbers.Length - 1
numbersString &= numbers(i).ToString & " "
Next
textbox2.text = numbersString
I tried coding for an application that will display the positive integers, negative integers and zero entered in a inputBox. for some reason it keeps crashing down.here is my code. paging all visual basic professionals. [code]
View 6 RepliesBasically I have and array of integers that vary in size. I need to compare each number to each other number and display which number is repeated. For example:
Dim ints() As Integer = {1,2,2,5,4,6}
The number that shows up more than once is 2.
How can I run through the array and compare each integer with the numbers in the array. I tried a for loop but it didn't return the value I was looking for.
I'm learning about GAC and signing assembly! And I have some problems...1. I make a DLL having some basic functions in ONE SOLUTION (Signed and Compile)2. Then, I make a FormApp, add a reference to this DLL and using its function to do somethings in OTHER SOLUTION. No error appears!3. I run this project, so I get an error:A call to PInvoke function 'MyDLL.LunarDate:: ' has unbalanced the stack. This is likely because the managed PInvoke signature does not match the unmanaged target signature. Check that the calling convention and parameters of the PInvoke signature match the target unmanaged signature.
I tried 4 possible abilities that I can image:
1. I unsign DLL and re-add it to FormApp : It's OK
2. I sign FormApp with same pnk : The same error
[code]....
I'm searching for a way to validate (or bypass validation for) self-signed SSL certificates using VB .Net. I found code to do this in C# and tried converting it into VB code, but I'm not having any luck.
Here is the C# code. Here is what I tried:
Imports System
Imports System.Net
Imports System.Security.Cryptography.X509Certificates
[Code]...
I have an array of Bytes. Most of these are interpreted as Unsigned. On certain occasions I need to interprete the byte as signed. Why can't Byte convert to SByte? What I'm doing: I'm trying to program a disassembler for an 8-bit video game ROM. My program reads the ROM and processes each instruction. The instructions are interpreted as unsigned. Some arguments for instructions would be treated by two's complement in the original hardware, however, to make a signed number.
View 8 Repliesi want to use an unsigned 32 bit integer. According to [URL]the rage of that type is
UInteger
UInt32
4 bytes
0 through 4,294,967,295 (unsigned)
[code].....
I have an VB.Net/C# application that allows programatically:
Creates an RTF document
Open it up in Microsoft Word
Runs a Word macro that exists in the Word Template using code like this:
[code].....
Looking for some .net snippet on accessing what users are logged into a domain. I have looked through all the AD namespace and okay with that in getting static items. Specifically, NOT looking for current logged in user for a given machine(have that as well). Looking for a list of users that are currently signed into a Domain.Essentially, I want to pass a user (or list of users) to a method that will check to see if the user passed in, is currently logged into the network (AD).
View 6 RepliesI am trying to write a VB.NET program that will call a function in an unmanaged C DLL passing the structure like this:[code]What I have not been able to figure out is how to handle the "unsigned char *msg" part. How would you define this in the VB.NET Structure?
View 2 RepliesWhy does this not work ?
[code...]
I get "tostring cant be called without a narrowing conversion"
I am trying to create a UInt128 structure, based on some C code I found. The 128 bit number is stored as two UInt64's. All was going well until:1. I tried to define MaxValue and MinValue. The code I found was
[code]...
I am trying to create a UInt128 structure, based on some C code I found. The 128 bit number is stored as two UInt64's. All was going well until:
1.I tried to define MaxValue and MinValue.[code]
2. I tried to add. Apparently in C if you do the equivalent of this:[code]you do not get an overflow, the result "wraps".
here know how to do to sign a file with certificate chain and crl embedded?I don't have ideia how to do that.
View 5 RepliesI'm looking for a way to locate signature field on PDF using VB.Net Or JavaScript and Acrobat and then I want to check if it is signed or not. Here is what I have so far:
Dim page As Acrobat.CAcroPDPage
Dim annot As Acrobat.CAcroPDAnnot
page = acroPDDoc.AcquirePage(0)
[Code]....
Im finding the annotations but I dont know how to check if it is signature field or not.
Im using the SSL stream class to connect to a server and authenticate their self-signed certificate. My authentication code gets an error: "RemoteCertificateChainErrors". When I drill down into the X509ChainStatuses, I only see a status of "UntrustedRoot" and status information of "A certificate chain processed, but terminated in a root certificate which is not trusted by the trust provider." This seems acceptable due to the self-signed nature of their certificate. I understand that I can ignore this error. However, Id like to do as much as possible to authenticate. I have a certificate from them. Ive been told to add their cert to my root certs somehow. How do I correct my code use this cert in authentication?
[Code]...
I need to be able to write signed bytes to a serial port using SerialPort.Write() method, except that method only takes byte[] arrays of unsigned bytes, how would i write a signed byte to the serial port?For what I'm working on the particular command takes values from -1700 to 1700.
View 1 RepliesHow can I write a signed byte (sbyte) to unmanaged memory using VB.NET? I can use Marshal.WriteByte() to write an unsigned byte, but there doesn't appear to be an overload for signed bytes.
View 1 RepliesI'm new to VB.Net. I'm using a library call setInstance(ByVal instance As UInteger) in my VB.Net code. The parameter I need to pass is an Integer. Is there anything I need to do to convert the integer parameter to an unsigned integer? The number is garunteed to be positive and less than 10.
View 3 RepliesI'm trying to generate random dates in between two dates that are selected with a date and time selection control.Ideally, I would like to get the 'ticks' of each date, generate a random number between those, and then convert that back into a date.However I'm getting arithmetic overflow errors when I try to generate a random number from the between the ticks. I've tried many approaches - directly seeding with both the low and high date ticks, as well as subtracting.
Private Function randomDate() As ULong
Dim rand As New Random(Date.Now.Ticks Mod Integer.MaxValue)
Dim holder As ULong = DateTimePicker2.Value.Ticks - DateTimePicker1.Value.Ticks
[code].....
Newbie here I need to send a email with and attached file (a *.xls file) The condition is that the e-mail need to be signed and crypted. I already got a digital certificate sign (provided by Verisign). I also read something about X509Certificate2 Class on MSDN, and something about Outlook interop Model. My idea was use the Outlook Interop Model Class (from Outlook 2007) but i have no idea how to do this.
View 1 RepliesHow can I implement a two's complement in VB.NET using unsigned integer types such as Byte, UShort, UInteger and ULong? Can I cast a UInteger to an Integer?
View 1 Replies