Dealing With Null Terminated String?
Feb 1, 2010Is there any way to convert null terminated string to normal string.I mean I can easily make a program to find the location of vbnull but there has to be a built in function for that.
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Convert Null Terminated String To Normal String?
Dec 16, 2009Is there any way to convert null terminated string to normal string.I mean I can easily make a program to find the location of vbnull but there has to be a built in function for that.
View 1 RepliesReading A Null Terminated Byte?
Mar 29, 2011I'm reading a binary file. Apparently its older, and some of its values are based not on position, but on null terminated bytes. Position 17 thru 35 represents a value, however, if their is a null byte at 30, then you get garbage if you try to read 17 thru 35 as a value...
I need to read, specifically, from 17 to 29 in this instance because pos 30 is a null byte.
Have to read it byte by byte, no problem. Not sure though the syntax of comparing a null byte specifically.
If you need a sample of the binary file, I can post it.
C# - Returning List Of Null-terminated Strings From External Function Into .NET
Mar 29, 2012I am trying to call an external C++ function using VB.NET (answers in C# are fine, I can convert back) which returns a list of device names. This comes in the form of a pointer to a null-terminated array of null-terminated char arrays (correct me if I've misunderstood what I'm dealing with) with a function signature:
long GetNames(char*** names)
Most of the answers to similar questions I've found have involved something more like:
long GetNames(char** names, int length)
It appears from what I've read that I need to give it an IntPtr but I'm uncertain as to how this should be initialized, and in my case I don't know the length of the array. At the moment, in the VB module, I have:
<DllImport("MyExternal.dll", CallingConvention:=CallingConvention.Cdecl)> _
Function GetNames(ByRef names as IntPtr) As UInteger
End Function
I've tried calling the function by passing an IntPtr initialized as IntPtr.Zero or using Marshall.AllocHGlobal, but I always get an AccessViolationException.
Any ideas on how I should be calling this function and how I get the return value into a managed string array would be greatly appreciated.
EDIT: I've found a sample function call in native C as follows:
char **tmplist;
GetNames(&tmplist)
Asp.net - SQLDataReader: Dealing With Null Values?
Feb 9, 2010Some tables I am dealing with have null values and are throwing errors. So far ive tried a few solutions to deal with the nulls with no success.Here are the code samples from my efforts so far;
If (r("datemodified").Equals(DBNull.Value)) Then
datemodified = String.Empty
Else[code]....
i have ran the query and it is working ok (i.e all the cols exist)
Dealing NULL Values In SQLDataReader
Jan 12, 2012Dim myreader As SqlDataReader = cmd.ExecuteReader
'read information from the database and give the values to the arguments(column_1, and column_2)
While myreader.Read
column_1 = myreader.GetString(1)
column_2 = myreader.GetString(2)
.....
I get an error when the data returned from myreader.GetString(2) is NULL. How do I check for nulls before assigning column_2 a value?
Dealing With A Null In A Varbinary Field
Aug 3, 2009I'm trying to test a varbinary(max) field to see if it's null. I'm trying to figure out if it's a null or not in the select statement, hoping to avoid having to do this locally for every row of the returned dataset. This is the SQL I'm using,
[Code]....
SQLDataReader: Dealing With Null Values?
Jul 8, 2010Some tables I am dealing with have null values and are throwing errors. So far ive tried a few solutions to deal with the nulls with no success.
Here are the code samples from my efforts so far;
If (r("datemodified").Equals(DBNull.Value)) Then
datemodified = String.Empty
[code].....
Properly Dealing With Null Database Values In .net?
Jan 1, 2012I am looping thorugh a datatable and and printing each row to the console and I keep on getting a dbnull error. I inserted an if statement in my loop to try and catch it, but I can't seem to get it to work.
[Code]...
.net - What To Do When Dll Return A String Not Correctly Terminated
Mar 10, 2009I have an third part dll that have a function that returns a string.When I call the function I got for example "123456" back. At least it seams like that, but when i do mystring.length it does not return any length. If I set the text property of a label it shows "123456".
When I have the string I got from the dll I send it to a webservice function:
rem call dll and get string
dim mystring as string=mydll.getstring()
rem Send it to the webservice
webservice.SaveString(mystring)
The webservice crashes with an webexeption ("protocoll error") when I send in the string I got from the dll. If I instead send it like this:
rem call dll and get string
dim mystring as string=mydll.getstring()
rem Send it to the webservice
dim FixedString as string = mid(mystring,1,6)
webservice.SaveString(mystring)
Then it works and everything is fine. That leads me to think that the string I got from the DLL is in someway not terminated correct.And I dont know how to fix it from vb.net (I cant change the DLL)and I dont know in beforehand how long the string will be.The dll does only work on site when specific hardware is connected so I can't sit at the office trying to fix this in dev-environment. So I would like to have some possibly solutions to this before I go to the customer again.
Edit 1:I tried to just do a loop that looped from 1 to 100 (because I dont know the real length) and tried to copy all characters that <>"" to a new variable but it didnt work. I didnt try other variants because the day was over and I had to leave the customer site.
Edit 2:The DLL Im talking to is made in VB6. That DLL is talking to other DLLs that is made in C++ (I think).
My program < - > vb6-DLL <-> c++-DLL <-> hardware
Sql :: String Or Binary Data Would Be Truncated. The Statement Has Been Terminated?
Jan 2, 2012String or binary data would be truncated. The statement has been terminatedAs I've looked back on my backend or code. It looks like there's a conflict adding a TWO LABEL DATA in one column because I would like to join the (Year)-(StudentNumber)Here's the code of my INSERT INTO Statement
INSERT INTO
[Student_Information] (StudentID, LastName, FirstName, MiddleName, Gender,
ContactNumber, Citizenship, Religion, Birthday, Address)
[code].....
String Or Binary Data Would Be Truncated - Statement Terminated
Mar 8, 2012This gets data from Excel and puts it into a table. The first 2 rows of data are placed into the table. All the fields columns are the same type and nothing is larger than it should be name is varchar(30) team is varchar(3) pos is varchar(2) rest are int or double. I place an i in front of integers s in front of string and so on. The 3rd row crashes with the following message at Command.ExecuteNonQuery() String or binary data would be truncated. The statement has been terminated.
Option Strict Off
Imports System.Data.OleDb
Imports System.Data.SqlClient
Public Class Form1
[Code] .....
String Or Binary Data Would Be Truncated The Statement Has Been Terminated?
Jul 4, 2011Protected Sub cmdOK_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmdOK.Click
Dim medID, medName, comment As String
[code].....
Error : String Or Binary Data Would Be Truncated.The Statement Has Been Terminated
Apr 16, 2009Am using Vb.NET 2008 and SQL 2008. I have a problem, when the execution reaches daAdapter.Update(dtTable) then I receive this error ""String or binary data would be truncated.The statement has been terminated"" Then the record fails to update.Below is the complete code. Thanx in advance.
Dim SQLCon As SqlConnection
Dim SqlQuery, SqlQuery1 As String
Dim daAdapter As SqlDataAdapter
[code]....
Error- 'String Or Binary Data Would Be Truncated.The Statement Has Been Terminated'
Feb 27, 2012iam trying to insert some values to SQLServer 2005 Database.The following error displaying.I changed the corresponding column size,still the error persists.how can i sove this error-:'String or binary data would be truncated.The statement has been terminated'
Me.Personal_detailsdbTableAdapter.Insert(Me.FirstnameTextBox.Text, Me.LastnameTextBox.Text, _
Me.PassportnoTextBox.Text, Me.PlaceofbirthTextBox.Text, _
Me.SexTextBox.Text, Me.DobDateTimePicker.Value.ToString)
This is the SQL Database Table Design
firstnamenvarchar(50)Checked
lastnamevarchar(20)Checked
passportnonvarchar(50)Unchecked(Primary Key)
[code]....
.net Log In With MS Access 3 Attempts Then Account Will Terminated/lock?
Mar 15, 2012I need to be able to terminate/locked the account in vb.net if the user input wrong username/password in my Log In form like 3 attempts is good. and be able to enabled the account also as an Admin.
View 12 RepliesDB Null String Need Values
Jun 9, 2012I doing a project for my office. In that I am showing the values and strings from a particular table based on the date range and vendor selection. It is working fine with the date range. Except within the date range if the particular reader has no data it throws an error message like dbnull string.
[Code]...
How To Convert Null Value To String
May 23, 2010foreach (PropertyInfo PropertyItem in this.GetType().GetProperties()) {
PropertyItem.SetValue(this, objDataTable.Rows[0][PropertyItem.Name.ToString()], null);
}
In one of the loops i get this exceptional error:
Object of type 'System.DBNull' cannot be converted to type 'System.String'.
The error occurs because one of the fields in the database has no value (null), so the string property could not handle it. How can I convert this null to string? I'm trying to avoid checking on every loop is current value is null or not.
Remove A Null From A String?
Nov 4, 2009This should be simple but apparently it's not. I have a text file, 694 bytes. At byte 500 there's a null in the file. I've tried reading it as text and binary and I end up with a string, 694 bytes long. But anyting I do with this string fails because it appears to stop at character 500. I can do a ? asc(mystring.substring(549,1)) and I get 9 (tab). Print character 550 and I get 0. Print character 551 and I get 32 (space). How do I get rid of this null?
View 5 RepliesAsp.net - Converting Null String To Date?
Jun 24, 2011The user will select an entry in a gridview, which then redirects them to a form that is populated with the data from the selected row (thus making the gridview editable in a more user friendly way). Null values are accepted by the DB and I would like to show null date values as blank (or " ") in the corresponding text boxes. Instead I get the error:
Conversion from type 'DBNull' to type 'Date' is not valid.
Here is my code:
'preceded by connection code
Dim sqlcmd As String = "SELECT * from Master WHERE RecNum = @recnum"
'Dim sqlCmd As New OleDb.OleDbCommand("SELECT * from Master WHERE RecNum = @recnum", connection)
Dim FileCommand3 As New OleDb.OleDbCommand(sqlcmd, connection)
[code]....
Assigning Null Value To String Variable
Jul 4, 2010How can I assign a variable which may contain a null value to a variable which is declared as Dim var1 as String and then use that variable to insert into access database table?
View 3 RepliesConvert NULL String To Decimal?
Mar 30, 2010I tried this
Dim value As
String
Dim returnValue As
[code]....
Error - Value Cannot Be Null. Parameter Name: String
Feb 23, 2011I get the following exception for the code shown below. The error occurs when i request access token.I downloaded the latest dll(2.3.1) from the twitterizer website.
{"Value cannot be null. Parameter name: String"}
Dim OAuthTokens As New OAuthTokens
Dim accessToken As New Twitterizer.OAuthTokenResponse
accessToken = OAuthUtility.GetAccessToken(ConsumerKey, ConsumerSecretkey, "oauth_token", "oauth_verifier")
Null String Yield An Error
Sep 10, 2009I have the following code below which has an error. When the checkbox is set to true and for example change the "role", and click save the following error is given;
"Index was outside the bonds of the array".
I know the reason of the error but don't know the solution..
The TxtPayCont is a concatenation of title, fname, and lname in an array. Therefore, if all the fields have values, then it works fine. So if it is Mr Jones Tim, this works, but, if it is Mr Jones it does not. It has to have 2 spaces to work. Is there anyway round this...
(see code below)..
Code:
Pass The String As A NULL If Nothing Is Passed?
Oct 31, 2011If I send a String set to Nothing as an input parameter to a SQL stored procedure, and in the sproc it's like this @MyString Char(9) = NULL, what does it turn NULL into? Because I'm firing the sproc and it's not firing the statement that says IF @MyString = NULL... So I don't know what it is... Or how can I pass the string as a NULL if nothing is passed as a parameter to my calling function?
View 4 RepliesSign Every End Of A String With Binary NULL?
Jul 20, 2009In my project i need to sign every end of a string with Binary NULL, how do I write Binary NULL?
View 6 Replies.NET - NULL Object If Assigned String Length Is 0?
Jul 12, 2010Currently, whenever I pass a string to the db, if that string is empty, then i set that object to NULL by doing the following:
IIf(DescriptionTxt.Text.length > 0, DescriptionTxt.Text, DBNull.Value)
I was thinking about writing a function to reduce the length of this code, and make it more consistent.However, I was wondering, is there already a way of doing this in .NET 3.5?
Fixed String With Embedded Null Characters
Mar 26, 2010I am using a com object to maniplate data inside an external program using VB.NET. One of the methods this com object provides requires 1 string parameter.The external program, however, requires a sting of a specified length, regardless of the number of characters used. The string to be passed to the function (length 36) is a combination of the below key fields.[code]I have tried the VB6 compatability's VBFixedString type but the com object's method throws an exception due to a type mismatch.If I convert the VBFixedString back to a .NET string before passing it to the method, the first null character is again interpreted as a string terminator and the rest of my string is chopped.
View 1 RepliesSelectedvalue Method Returns Null String
Jun 29, 2011I'm converting a system of numerous programs from foxpro/foxweb/javascript to asp.net/vb/sql server.
I'm coding for a dropdownlist which is currently controlled via js.
I don't like using the control this particular way, but I want to maintain look and feel for the customer.
The control is initialized with some values via Page_Load() in behind code.[code]...
VS 2010 String.Length() Returns Null
Jun 11, 2011[Code]...
By my logic, this should only assign .length to index IF the length of strItem is longer than 0. This check is there in case the listbox is empty, or the user has not selected an item. However, everytime I go through this code without an item selected I get:
[Code]...