The below program throws a runtime error (invalid conversion from double) because there is [code]It compiles fine, but when the program is run, it throws a runtime error.Is this a compiler bug? Shouldn't it stop me with a compiler error, like invalid syntax ?
View 2 RepliesI have a simple question about string concatenation. Following is the code. I want to ask why s6 = "abcde" and not "akcde"? I have change the s2 value to "k".
Public Class Form1
Public s1 As String = "a"
Public s2 As String = "b"
[Code]....
I've spent the last 3 hours trying to figure out why this string won't concatenate.
The function takes in a mapped drive letter and creates a UNC path and returns it.
Any thoughts welcome:
In VB.net, I tested concatenating 100k strings and found out one thread alone did it in 23 milliseconds. Two threads (each concatenating 50k) then joining the two at the end took 30 milliseconds. Performance wise, it didn't seem beneficial to utilize multiple threads when dealing with only 100k concatenations. Then I tried 3 million string concatenations and two threads each handling 1.5MM always demolished one thread handling all 3 million. I imagine at some point using 3 threads becomes beneficial, then 4, and so on. Is there a more efficient way to concatenate millions of strings in .NET?
fyi, this is the code I wrote:
Imports System.Text
Imports System.Threading
Imports System.IO
[code]....
Possible Duplicate: The difference between + and & for joining strings in VB.Net.In VB.NET you can use either += or &= to concatenante a string (ignoring using a StringBuilder for this question -- this is directed at a very simple concatenation).
View 2 RepliesI am facing a really very interesting problem with string.
My code is
[Code]....
But when I comment those lines (which are uncommented in code above) its working fine.
I am taking value in filepath variable from file dialog's FileName property.
EDIT: I have also compared the values of variable stropt and strwithpara with "IF" condition and found those are same.
I'm trying to concatenate two properties into one string like so:
public class thing
public property word() as string()
public property count() as integer()
[Code]....
This is what I want, but it doesn't help that its in the debug output...I need to put it into a single string. I've tried using a_thing.count(i).tostring, but it doesnt work. If I look at the arrays individually, they have exactly the contents I want. But I can't concatenate them. Does it have something to do with suppressing the new line that debug.writeline usually creates?
The intent of the code is to open an xls file -minimize it , search for keywords . there are columns like test case name ,priority(simple ,medium and high) with associated keywords.If keywords are found, it shld save the test case name - Priority in a text box. When i run this code i am getting err in
[Code]....
I've got a small app which I use to start a 3rd party application. When run from a shortcut the VB app starts the 3rd party app to and when loaded it displays its own file/folder interface, the VB app the closes itself. However, if you open a file in explorer associated with the 3rd party app, the 3rd party application loads and opens the file itself and not the file/open interface.
Uh OK, so what's the problem??The issue is I have changed the file extension associated with the 3rd party app to now use my VB app. I can successfully open files with the app from explorer if there are no spaces in the file or folder path however if there are, the 3rd party app opens and displays a File not found error message and gives the path up to the point where the space then follows.The relevant snippets of code from the app relating to the issue is below, specifically Dim Arguments variable where I am not quite sure how my string cocantenation should be to deal with the value of the variable 'Filename' which may or may not contain spaces.
[code]...
which compiler errors would be detected out by VB compiler?
I have searched out some compiler errors list for C#, for example, see the website at [URL]
MS provided us the information about C# compiler error. Does MS provide VB compiler errors information as well.VS
This is more of a curiosity question on what the VB compiler is doing. Basically the following code generates an error,
If "String" = CInt(1) Then
End If
As it should. What makes me curious is the error reported is
Conversion from string "String" to type 'Double' is not valid.
So, I guess my question is, why is the compiler attempting to convert to a Double when I would assume it should be converting to Integer?
Imports System.CodeDom.Compiler
Public Class iCompiler
Public Shared Sub GenerateExecutable(ByVal Output As String, ByVal Source As String, ByVal Icon As String)[code].....
The following output produces a string with no closing xml tag. m_rFlight.Layout = m_rFlight.Layout + "<G3Grid:Spots>" + Me.gvwSpots.LayoutToString() + "</G3Grid:Spots>"
This following code works correctly
m_rFlight.Layout = m_rFlight.Layout + "<G3Grid:Spots>" + Me.gvwSpots.LayoutToString()
m_rFlight.Layout = m_rFlight.Layout + "</G3Grid:Spots>" 'add closing tag
What's going on here, what's the reason the first example isnt working and the second is?
The gvwSpots.LayoutToString() function returns a string.
This error first appear to occur randomly. Steps to recreate:Open Visual Studio and load a solution (some files automatically opened) - this is when the problem occurs Close all open files Restart visual studio and load solution (no issues)Open Exactly the same files again, restart visual studio and load solution so files open automatically (problem occurs!)
However, when trying to narrow it down to a single file (that is automatically opened when the solution is loaded), I couldn't reproduce the problem. Now with all the files open again the problem doesn't occur!!! So it looks like it is fixed - though this happened before and eventually the issue came back.
I think it is to do with one of the user controls with DevExpress controls on it - when the error occurs, the designer displays the error. Though I can't reproduce it at the moment to confirm that.
If I look at the IL that is created in Linqpad for the two following code snippets, I wonder what happens here.
In c#
int i = 42;
results in the following IL code
IL_0000: ret
whereas in VB
Dim i As Integer = 42
it is
IL_0000: ldc.i4.s 2A
IL_0002: stloc.0
Apparently, the c# compiler understands the the value is never used and thus simply returns nothing. In VB.NET the actual code is translated.Is that due to differences in compiler optimization or is there anything else at work?
Update: Just to clarify this - I just enter this one line into LinqPad and look at the IL it creates (most definitely by running the respective compiler). There is no program.
Is there any difference between & and + operators while concatenating string?if yes, then what is difference? And if No, then why below code generating exception?
Example:
Dim s, s1, t As String
Dim i As Integer
s1 = "Hello"
[code]....
I am wondering how to concatenate a string and an integer to form a button name.eg, ("button" & x) where x is an integer to form button1, button2, etc so i can change the backcolor of the buttons.
View 2 Repliesi am currently working on a small project, but to be honest i am quite new to VB i am trying to run this code:
For i As Integer = 1 To box_select_solp
cell_solp_text(i).Controls.Add(New LiteralControl("SOLP" & i & "#: "))
Next i
I'm trying to compose a String from multiple Strings, where some of the Strings may be in Arabic letters, the problem is that when I concatenate them, their order is being messed !!
For example, I have the following Strings:
Ref1
مسكه
2
Left
I want to concatenate them with the same previous order seperated by "-", but instead I get Ref1-مسكه-2-Left, as you can see, 2 is written before مسكه Does anyone know how to fix this problem, because it's really important in my case to have the exact same order, and I don't know where or when I might have these arabic strings, because it's being entered by User.
I have a windows form having combobox and textbox controls.. I have to generate a part number, consisting of combobox and textbox values included.. I can explain in detail.. This is the code i have used to define a variable "type"..
[Code]...
I am creating a program to simulate a tenpin bowling scoring system, and I'm using labels with the following name structure:
Player1Frame1Ball1, Player1Frame1Ball2, etc..
I have following variables also: CurrentPlayer, CurrentFrame, CurrentBall
I am hoping to use these variables to specify which label I would like to check the value of (the score achieved, placed in the label).
To test my experiments I have been trying to output the score of the first ball in the current frame in a msgbox, but to no success:
[Code].....
When I am concatenating object values together to form a string in VB.NET, is there a difference in performance or a recommended best practice between using the & concat or the + concat with calls to .ToString() on each object?
Example (which is faster or best practice):
Dim result1 As String = 10 & "em"
Dim result2 As String = 10.ToString() + "em"
I have combobox for year and combobox for month concatenated to make the date format "2012-01" My db field is RecordDate and is smallDateTime In my select statement im trying to use the left function to find match my concatenated string to the RecordDate field.Here is my code, hopefully someone can help me. Currently im getting the error "Conversion failed when converting date and/or time from character string."
Dim newRecordDate As String = (CStr(ComboBox2.SelectedValue)) & "-" & val1
Dim val10 As String = CStr(Convert.ToDateTime(newRecordDate))
Dim val21 As String = Microsoft.VisualBasic.Right(val10, 7)
MsgBox(val10)
[code]....
1) is vb6 is interpreter based languge or compiler based or both interpreter and compiler based language?
2) is VB.Net interpreter based languge or compiler based or both interpreter and compiler based language?
3) if any of above mentioned is both interpreter and compiler based so tell me please when it compiles and when it interprets?
how to create my own programming language,I can create a compiler for a language like vb.net itself. Essentially, the user inputs code, they get a .exe. By NO MEANS do I want to write my own language, as it seems other compiler related questions on here have asked. I also do not want to use the vb.net compiler itself, nor do I wish to duplicate the IDE.
The exact purpose of what I wish to do is rather hard to explain, but all I need is a nudge in the right direction for writing a compiler (from scratch if possible) which can simply take input and create a .exe. I have opened .exe files as plain text before (my own programs) to see if I could derive some meaning from what I assumed would be human readable text, yet I was obviously sorely disappointed to see the random ascii, though it is understandable why this is all I found.
I know that a .exe file is simply lines of code, being parsed by the computer it is on, but my question here really boils down to this: What code makes up a .exe? How could I go about making one in a plain text editor if I wanted to? (No, I do not want to do that, but if I understand the process my goals will be much easier to achieve.) What makes an executable file an executable file? Where does the logic of the code fit in?
This is intended to be a programming question as opposed to a computer question, which is why I did not post it on SuperUser. I know plenty of information about the System.IO namespace, so I know how to create a file and write to it, I simply do not know what exactly I would be placing inside this file to get it to work as an executable file.
I am underway to develop a VB.Net compiler using visual studio 2005, but so far I am not aware on how to go about, regarding to what are the key requirements or skills required for developing a compiler.
View 3 RepliesHow can i make my own compiler ?
View 5 RepliesI have a program using vs 2008 (as 3.5) and code in vb. The site has been running nicely for 3 years, but suddenly the error message has come: BC 30451 Name 'class 2' is not defined. Call Class2.open_connection(cn, Session("datapath")) But in my local computer and in the site server the particular line mentions class1 only and not class 2!
View 5 RepliesI am running visual studio 2008 with SP1 installed. I have a solution which has 7 projects. One of the vb files (which has some 15000 lines) is freezing the visual studio and when i close the studio it shows the visual basic compilation error. I have tested the solution in other workstations and it is running fine. I tried repairing visual studio and i tried reparing 3.5 sp1.
View 1 RepliesI downloaded Microsoft Visual Basic 2010 Express and I can produce programs using it, but I'm interested in using another editor.I searched the web for the compiler and apparentely it's called "vbc.exe", but I don't seem to find it in my machine.I'm supicious that it only comes with the non-Express version.
View 5 Replies