.NET Data-type Smaller Than A Byte?
Jul 9, 2010How about a Nibble etc.
View 3 RepliesHow about a Nibble etc.
View 3 RepliesIm working on a FTP Server (File Transfer Protocol) where i can download files.The problem occoured when i was about to download a 4BG large file from the server when i only had 3GB RAM on the server computer and the function to read the binary files was " data = File. ReadAllBytes("Files File001.7z") "... so how do i split the binary file into smaller byte blocks like 1MB?I've been trying this which seems to have been a total failure.[code]
View 11 RepliesI don't understand that error that occurs on the second line of code below. I'm trying to skip over the first 18 bytes of a byte array that I'm accessing from a c# dll into a local vb.net byte array
View 3 Replieshow 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
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Imports System
Imports System.Data
Imports System.Data.SqlClient
[coe]....
I 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'"
Is it possible in VB to truncate a larger data type ( an int with a value greater than 255) to a smaller one, say a Byte (which only goes up to 255) in a way such that the 8LSBs of the integer are copied to the newly created byte. I have tried this using CType with the following code, however it does not work.
Dim TestByte As Byte = CType(Test, Byte)
Where the variable "Test" is an integer with a value of 419. This code always results in the Overflow exception.
[code].....
I have been working on a much larger project and came to a point where I decided threading should be used.It seems in previous version of .Net, a background worker was able to update controls that were were not created on that thread. Now, it doesn't seem to be the case.I basically just began a new small project to try and teach myself the basics.Form1 Consists of A listbox, A progress bar, a label and two buttons, one to start and one to cancel.
imports system.threading
private sub btngo(byval sender as system.object, byval e as system.eventargs) handles btngo.click
pbprogress.minimum = 0[code=....
This code appears to be updating the listbox.I can see the vertical scrollbar getting smaller, but no data is shown in the listbox. The progressbar is also updating properly while that is working, indicating proper background operation.But what it's not doing is this:
1. Label is not updating percentage
2. The form is not free to be used by the user (me)
I'm really hoping I can describe this question in an understandable way. This is a puzzle that I have not been able to begin to solve even though I (mostly) understand it. I'm just not sure where to start, and I'm really hoping someone out there can get me headed in the right direction.
I have a LARGE table of data. It describes relationships between objects. Let's say the Y-axis has items numbered 1-1000, and the X-axis has items 1-1000 also. If item #234 on the Y-axis is related to item #791 on X, there will be a mark in the table where the row and column cross. In some industries this is referred to an a Truth Table. One can, at a glance, see how many items in a system relate to each other. The marks in the table can help to identify trends and patterns.Here's some other helpful stuff about the nature of the table:
The full range of the number of relationships (r) for each item on either axis can be 1 <= r <= axisTotal.The X and Y axis will share common items, but each axis will also have items that the other axis does not.Each item will only exist once per axis. It can be on X and Y, but it would only be on each one 1 time.The total number of items on each axis will most likely NOT be equal. Each axis could have from 50 to 1000's of items.
The end result is that this is going to be a report that needs to be printed. We have successfully printed a table that had about 100-150 items on each axis on an 11in X 17in piece of paper. Any more than that and it begins to be so small it's unreadable.
What I am trying to do is split the super large tables into smaller tables, but related points need to stay together. If I grab item 1-100 on X then I would need each item they relate to from Y.I've generated a number of these tables and, while the number of relationships CAN be arbitrary, I have never seen an item relate to all other items. So in real practice the range is more like 1 <= r <= (10% * axisTotal). If an item's relationships exceed this range, it can be split up into multiple tables, but that is not optimal at all.
At the end of the day I think we, and our clients, would be happy if a 1000x1000 item table was split into 8 to 10 printed pages of smaller, related tables.One other thing worth noting, there will be no empty rows or columns in the table. Every item on both the x and y axis will relate to at least 1 item on the opposite axis.
Now I want to display picture in picturebox1.To do this I use this codes, but it does not display picture
on this line: Dim arrPicture() As Byte = CType(dt2.Rows(0)("img_path"), Byte())
it shows this message,
Unable to cast object of type 'System.DBNull' to type 'System.Byte[]'.[code]......
I am using VB2008 in VS Prof and try to convert at Byte arry stored as a Image format in Sql2000 database.
Code:
Using acnLoc As New SqlConnection(CSLoc)
acnLoc.Open()
Dim G As SqlCommand = New SqlCommand("SELECT [SignatureData] FROM [MyTable] where [OID]=@OID", acnLoc)
G.Parameters.Add("@OID", SqlDbType.Int).Value =Cint(bxShipmentno.Text.Trim())
dim P= G.ExecuteScalar() 'returns a system arry
[Code]...
i get the error in following code
Function ReadFile(ByVal sPath As String) As Byte
Dim data As Byte
data = Nothing
[Code].....
I has the following code in my vb.net:
Code: Dim sql2 As String = " SELECT * FROM Etiqa_Image_Details where TransmissionID='" & Request("id") & "' " With objDB.OpenDataReader(sql2) While .Read()
If .Item("ImageType") = "Invoice" Then imgInv.ImageUrl =
[code]....
However,i get this error while retrieving the image path(Varchar in sql server 2000) and display the image on the web.
Unable to cast object of type 'System.String' to type 'System.Byte[]'.
Actually in my database, i am just storing the image path where the image store...And now when I browsing the web, it should get the image path out and find the image through the image path and then display on the web....
For each column in data table i want to add parameter with same data type as column data type. But looks it's not that simple.
Dim cmd As New SqlCommand
Dim dType As New System.Data.SqlDbType
For Each cl As DataColumn In DataTable1.Columns
[CODE]...
How can I do this?
Why I am I getting the "type byte has no constructors" error here?
Dim stream As System.IO.MemoryStream = New MemoryStream()
bitmap.Save(stream, System.Drawing.Imaging.ImageFormat.Jpeg)
Dim image As Byte() = New Byte(stream.Length
Why does C# define Byte+Byte=Int32 instead of Byte+Byte=Byte like VB?
View 1 Replieshere's a glimpse of byte array sendFrameData just before the Exception is thrown.I'm trying to figure out why the c# code worked as listed below but the vb.net throws the error.[code..]
View 3 RepliesI have used the following code to read a memory address from a pointer and offset previously however, Now I've come to use it again and can't figure out how I got it working last time, I'm receiving the error "value of type '1-dimensional array of Byte' cannot be converted to integer" highlighting the BytesAtAddress variable in the ReadProcessMemory calls.
Public Shared Function ReadPointerFromMemory(ByVal BaseAddress As Integer, ByVal PointerOffset As Integer, ByVal BytesToRead As Integer, ByVal pHandle As IntPtr) As Integer
Dim BytesAtAddress As Byte() = New Byte(BytesToRead - 1) {}
[code]....
here's a glimpse of byte array sendFrameData just before the Exception is thrown.I'm trying to figure out why the c# code worked as listed below but the vb.net throws the error.
byte[] sendFrameData = new byte[280];
byte[] ByteArrayMessageForDevice;
byte[] toSocket_IPP;
[code].....
I am writing a VB.net client to write to and read from a named pipe in byte transmission mode.I learned from the MSDN article that CallNamedPipe() only works for message-type named pipes.
So do I have other choices, or do I have to change the pipe server code to message type.
How can I write this in an other way?System.IO.File.Copy(My.Resources.xxx, TextBox1.Text + "" + "blabla")I need to write this in an other way because I get this error:Value of type '1-dimensional array of Byte' cannot be converted to 'String'.
View 2 RepliesAt the top of the code that follows is the method in c# into which I'm attempting to pass an integer value. Is there anyway I can change the assignment statement to the byte() PDUToSend to take care of the error I currently receive; Value of type 'Integer' cannot be converted to '1-dimensional array of Byte'.
CODE:
I need to create a function which have either 1 parameter with a string as data type or 2 parameters with double as data type.Something like the substring method.
View 2 RepliesDim ScoreAddie As IntPtr = &H7FF824
Dim NewScore As Byte() = 999999
Dim p As Process
Dim myHandle As IntPtr
[code]....
Whats wrong?
I'v designed a ms access database table with one field having Datetime datatype. I can Insert data into it from vb.net front end by trns_dt DateTime.Now.DateBut when I fetch records from the tableand assign the dataset datasource as da, it shows datatype mismatch error.
daleDbDataAdapter("SelectDaily_Transactiondtp_from_dt.value dtp_To.value con)
dsDataSet
[code].....
i have a table in sql server with some fields set as Byte() (System.Byte[]) when i import them in my application to be used with linq they are converted in Binary (System.Data.Linq.Binary)why is that?is there a way to prevent this wrong translaton???if i update the database how can i update the classes that has been craeted in visual studio2008?
View 2 RepliesI have a program that calculates commission, but if the commission is nothing then I do not want it to show a zero commission. I want a message box to show a message that there is no commission earned.
View 1 RepliesMy colleague gave me a DLL that manage all database business. I wanted to invoke a function that uses Stored Procedure and return the search result. In the function receive a parameter type in ystem.Data.IDataParameter[]. Below is my codes.
[Code]...
I have a function (on vb.net) to get a data from a XMLWebService:
[Code]...
I added this lines in the form load of DataGridPrinter by Merrion in the codebank..[code]Unable to cast object of type 'System.Data.DataViewManager' to type 'System.Data.DataTable'.
View 2 Repliesevery time i run this code i get the same error
Unable to cast object of type 'System.Data.DataTable' to type 'System.Data.DataView'.
the code is
Dim plmExcelCon As New System.Data.OleDb.OleDbConnection
Dim cmdLoadExcel As System.Data.OleDb.OleDbDataAdapter
Dim PrmPathExcelFile As String
[Code]......