I am needing to write data to a usb device. The USB device uses a byte array (DataArray() as byte) to store the data. How can I assign a struct object (myStruct(0)) to the byte array. I run into the error "Value of type byte cannot be converted to 1-dimensional array of byte" when I try to cast the struct as a byte.
View 10 RepliesI just converted the following code from c# to vb.net. It is functional and works correctly with my company's firmware/devices. My next challenge. Previous serialport code used much more readable structs which where then converted (after building a packet) into byte() automatically as part of the serialport encoding. (this is my understanding)How could I
1. morph byte arrays 'ToSocket' and 'ToMTP' below into structs and
2. convert into byte array for Socket.BeginSend(byte(),.....) to stream out to remote devices?
Imports System.ComponentModel
Imports System.Text
Imports System.Net.Sockets
[Code]....
I'm converting a stream of bytes from a network packet into a specific struct, and vice versa. For example, when converting a short back and forth, my method looks like this:
myShort = buf(0) + (buf(1) * 256)
or the other direction:
buf(0) = myShort mod 256
buf(1) = myShort 256
When it comes to a 4 byte integer, after some experimentation I found that converting from the byte array to integer is done this way:
myInt = buf(0) + (buf(1) * 256) + buf(2) + (buf(3) * 256)
Basically adding two shorts together. I'm not quite sure to do the reverse of that, to fill the 4 bytes from myInt.
I am working on a mini project that requires me to take a 8 byte hex string that I received from the Serial Port and convert it into a Byte Array and display it on the screen.An example of the string that I receive is 01050001FFFF8FFB
I am currently using the System.Text.ASCIIEncoding.ASCII.GetBytes(str) to help me achieve this. However I realised that if this does not support extended ASCII so whatever byte that is > 7F, I will not get the right value.My current code is as follows:
vb
Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
Dim str As String
[code]....
I have a hexadecimal value
07A5953EE7592CE8871EE287F9C0A5FBC2BB43695589D95E76A4A9D37019C8
Which I want to convert to a byte array. Is there a built in function in .NET 3.5 that will get the job done or will I need to write a function to loop through each pair in the string and convert it to its 8-bit integer equivalent?
I'm calling a Windows API that gives me a byte array which represents a unicode string - the problem is that if I call Text.Encoding.ASCII.Get String on it I just get the first letter of the string. The reason for this is that byte array has an empty byte between each character. I've verified that removing these empty bytes resolves the problem by just using a simple For loop to add the bytes that do have a value in into a new byte array, then calling Text.Encoding.ASCII.GetString on that and that gives me the full string I'm expecting.I'm just wondering if there is any easier way of getting the working string though without having to do a loop and create a new byte array etc?
View 2 RepliesHow to convert memorystream byte array to csv file. I have GetExport method that converts rpt file to excelformatted memorystream and then returns that as a byte array. Is there a way to convert this byte array to a csv file? Due to some reasons I can only pass this byte array back to calling function.
Public Function GetExport(ByVal reportID As ReportID) As Byte()
Dim byteArray As Byte() = Nothing
Using expRptDoc As ReportDocument = New ReportDocument()
Dim rptFileName As String = Server.MapPath(ReportCommand.GetXMLReportPath(reportID))
expRptDoc.Load(rptFileName)
[Code] .....
I am looking for something that will convert a byte array to a string and back, anything in-build that does it as this method would:
To string:
vb
Dim b = ByteArrSerialize(Obj, Compress, EncryptKey)
Dim sb As New System.Text.StringBuilder
For Each item In b
sb.Append(Chr(item))
Next
To byte:
vb
Dim b(0 To Len(TheString) - 1) As Byte
Dim bCount As Long = 0
For Each item In TheString
b(bCount) = Asc(item)
bCount += 1
Next
i do not know why data type image on ms sql is not working ! so i choose to use varchar(max) as my datatype to store images.. but i do now know how to load it on crystal report..
View 1 RepliesI didn't think it fair to post a comment on Fredrik Mörk's answer in this 2 year old post, so I thought I'd just ask it as a new question instead..NB: This is not a critiscm of the answer in any way, I'm simply trying to understand this all before delving into memory management / the marshal class.
In that answer, the function GetByteArray allocates memory to each object within the given array, within a loop.Would the GetByteArray function on the aforementioned post have benefited at all from allocating memory for the total size of the provided array:
Dim arrayBufferPtr = Marshal.AllocHGlobal(Marshal.SizeOf(<arrayElement>) * <array>.Count)
I just wonder if allocating the memory, as shown in the answer, causes any kind of fragmentation? Assuming there may be fragmentation, would there be much of an impact to be concerned with? Would allocating the memory in the way I've shown force you to call IntPtr.ToInt## to obtain pointer offsets from the overall allocation pointer, and therefore force you to check the underlying architecture to ensure the correct method is used*1 or is there a better way? (ToInt32/ToInt64 depending on x86/64?)
*1 I read elsewhere that calling the wrong IntPtr.ToInt## will cause overflow exceptions. What I mean by that statement is would I use:
Dim anOffsetPtr As New IntPtr(arrayBufferPtr.ToInt## + (loopIndex * <arrayElementSize>))
I've read through a few articles on the VB.Net Marshal class and memory allocation; listed below, but if you know fo any other good articles I'm all ears![URL]..
I have a basic confusion between serial port and network TCP communication to devices.
My colleague uses a vb struct as the nice easy to read way to create a packet to send out via a serial port. Like this basic code sample below of his vb.net serial call followed at bottom by my c# tcp beginsend network call.
Can I use a struct as well to call out for my TCP network beginsend? By looking at the signature of BeginSend(Byte[] as the beginning of the signature for that method call to send data to a connected socket, I don't see myself being able to use a struct.
Public Structure PacketRecord
Dim SourceAddress As Integer
Dim DestinationAddress As Integer
Dim Length As Integer
[CODE].....................
in my project I use an Excel workbook as template. Right now, this workbook is located in the same directory as the exe-assembly and can be opened and manipulated by the user. To avoid this, I thought about adding the workbook to a ressource. That works. Problem: how can I convert the resulting byte-array/stream back to a workbook-object?I tried like this, but - obviously - the conversion fails:
Public Shared Sub test()
Dim wkb As Excel.Workbook
Dim bytes As Byte() = My.Resources.Template_1
[code]....
How do I convert between an image object and Byte Array?
View 1 RepliesI am working on a project and came to a junction. I have various data in a object array, myObj().
How can one convert Object Array to Byte Array
I dont know if i should be using Memory Stream, Buffer, etc.
I am getting this warning in my code, and for the most part I have ignored it.
Friend Sub StartTablet()
Dim success As Boolean
Dim eventObject As IntPtr = IntPtr.Zero
[code]....
So, I'm creating an array of labels. I have labels set up as:
labal1
label2
label3
etc...
I've declared the array as such:
Dim labelArray(5) As Label
Now, instead of assigning the labels one by one to the array (labelArray(0) = label1, labelArray(1) = label2, etc...), I was hoping to use a loop (there will be more than 5 labels). I have something like this, which obviously doesn't quite work:
For i = 0 To labelArray(i) = "label" & i Next
Is there a function that I can use to convert the labelName string to an object, or have vb.net see that as an object instead of a string?
I have an application which take image from a folder through system, Io.filestream and convert it into bytes and store into database as byte data format and same I retrive from database as byte format and convert it into image into datagirdview. now I want to convert it into again bytes from datagridview. How to possible the value of image in datagridview into byte format.
View 1 RepliesI am trying to communicate with an external device and i am trying to send a byte array to the external device via sockets but i am always getting a response the message size is too small so i am not sure what i have done wrong. Between the data type there should be no alignment present and all numbers are represented in little endian format. The char array is not null terminated as mentioned in the protocol specifications.
I have to send data based on a struct that embeds 2 other struct. So here's my vb.net code for the struct used to convert to byte array and the sending part.
Public Structure MESSAGETYPE_OIP_Login
Dim Header() As COMMANDHEADER
Dim UserName() As PSTRING
[Code]....
I 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.
In the code base I'm working in there have a method that has the signature
Public Sub SetDropDownValue(Of T As Structure)(ByVal target As ListControl, ByVal value As Nullable(Of T))
The method I am writing is passed a parameter of type object.
How can I cast the object into something that can be passed into the SetDropDownValue method?
I am trying to Convert a data field stored as IMAGE ( SQL Server 2000) using Java to a byte array using VB.NET Java uses signed numbers for a Byte array where as VB dosent. Can somone point me to how I can covert java byte array to VB byte array?
View 2 RepliesI have a text file with the following information:
-----------------------------------------------
Model: Accord
Manufacturer: Honda
Year: 2004
VIN: FJ235FJSLO323434DJS
[Code].....
how to setup my loop to insert the text data into my struct array.
Objective: Combine byte arrays, read specific sections, and then cut byte array at specified point.
Private Sub DataArrival(ByRef aBot As xyzSocket, ByRef theData As Byte())
Dim RDLength As Int32
If aBot.ReceivedData Is Nothing Then[code]....
I'm not sure if I have this right to begin with because I can't test it without having it completed.
how to upload file using fileupload control into sql database. I have class where i created insert function and getting info frm the .aspx.vb file
Class File
========
Imports System
Imports System.Data
Imports System.Data.SqlClient
[coe]....
I have 2 byte arrays. I want to merge these two byte array into 1 byte array.Usually, I just create a new byte array with length = byte array #1 + byte array #2. Then copy byte array #1 and #2 to the new byte array.do I have more efficient way to merge 2 byte array using VB.NET and .Net 4?
View 2 RepliesI would like to create a function so that I can pass a string and it will return me the binary value, I will use this later in other parts of the script but I am getting an error that I don't understand.
Private Function ConvertToMD5(ByVal OldPassword As String) As Byte
Dim NewPassword As String = ""
'The string we wish to encrypt
[code]....
On the "Return hashedDataBytes I get "Value of type '1-dimensional array of Byte' cannot be converted to 'Byte'"
I have 9 1-dimensional arrays of bytes and 1 of them is empty, I want to make the empty one equal to the others put together like you would a string:
Dim bla As String = "bla" & "bla" & "bla"
'now bla = "blablabla"
but instead:
[Code]......
How do I read a raw byte array from any file, and write that byte array back into a new file?
View 3 RepliesHow could you convert a IntPrt to a Byte Array (Byte()) ?
View 19 RepliesI have a byte array that I convert into a string like so Dim byt As Byte() = New Byte(255) {} s = New String(Encoding.ASCII.GetChars(byte))My question is when I look at the string in a debuger its clearly a normal string but when I compare it to what I know its supposed to be it doesnt equal. So i did a quick check and for some reason its return a string thats the length of 256 characters. So i did a s.trim and it still is 256 characters long.
View 1 Replies