Difference Between A Loop That Never Ends And A Loop That Ends?
May 25, 2010
I'm slowly learning about loops. I have a couple of questions
1) When a condition is being tested.. what does that mean? I don't understand the "condition" word.
2) What is the difference between a loop that never ends and a loop that ends?
I have the code for the loop that ends and the loop that never ends. I can see the difference in the code, but I don't understand what is making it different. Here is the code below.
I am dealing with a situation which I do not understand why the loop never ends. I have attached this example. I do not know what I am doing wrong.I have 8 x 8 array of integers (TheConnectionsValue (7,7))
I tried adding a loop inside this loop but continue to get the error "Null reference exception was unhandled" before the loop ends.
For rowIndex = 0 To dgvVisit.RowCount - 2 MessageBox.Show(dgvVisit.Rows(rowIndex).Cells("CoPayCharge").Value.ToString) For rowIndex1 = 0 To dgvPayment.RowCount - 2 MessageBox.Show(dgvPayment.Rows(rowIndex).Cells("CoPayPaid").Value.ToString) Next Next
I'm reading in an xml file, which is working fine with no problems, but I want to re-format one of the elements data attributes slightly.
The XML attribute output is currently Wind: NW at 6 mph
What I want to do is extract just the number from the string, I figured an easy way would be to simply play with the length of the string and assign it to another variable.
However, I've ran into a little problem.
I can use windRtrim = wind.Substring(0, wind.Length - 4) (Where windRtrim is the amended string variable and wind is the string from above)
This returns Wind: NW at 6
Which is great, but the problem now is trimming the correct number of characters from the beginning of the string as it'll be different if the number were to go over 9 (ie. 10 and above)
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When I run a certain project from within the IDE and an error would come up (just any error, like dividing by 0), it won't jump into the IDE showing me the line where the error occured, but the program is simply ended and I am back in the IDE!.With any other project that is not the case. I cannot work further on this project with this problem. Of course I did a PC restart, but that didn't solve it.
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1) I think while compiling it gives me this error: The source file is different from when the module was built.
2) While running the program it stops on the connect.Open() and has this error OleDbException not handled. Could not find installable ISAM.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click ' Import float volume data from Excel
Due to my FTP server not liking to upload .exe files in order to get my auto updater to work i have to rename the folder .file before i upload
after this is downloaded i need it to check the application folder for any files ending with ".file" and if it finds any to remove the ".file" so that it is just .exe[code]...
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Going from VB6 to VB10 I find VB10 has much easier ways of doing things, like getting command line arguments, getting all subfolders, etc, the hardest part is knowing what commands to use. Is there a better way to detect if a string ends with certain text? I'm doing it like this....
Deleting a line from a text file. This is for an ASP.net Webpage. I will have a file called Sources.txt. Example data of this file looks like this[cde]...
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I am trying to create a tool which executes some oracle procedures and telnet commands. Besides this Job my tool also needs to update a counter in some table in oracle db at regular intervals(10 secs as per current settings). So I used backgroundworker class in VB.NET to implement this back ground job of updating the counter. My problem is I have put logs at every possible exit of the backgroundworker_dowork functions but still this logic stops working after some time --7-8 hours. I am not able to understand when/where/why/how is it stopping? I am saying logic has stopped because it stops incrementing the counter. And am saying it is exiting abruptly because in _RunWorkerCompleted, I have written a log and closed the application but nothing comes in the log and application is not exiting.
Private Sub backlogicthread_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles backlogicthread.DoWork WriteLog("Background worker", "entered") dbbackcontrol = New OracleConnection(odbcBill) Dim dr As OracleDataReader [Code] .....
Makes the following statement about the code below:
**"The computer evaluates the loop condition in the Do...Loop statment to determine whether the loop instructions should be processed. In this case, the inputsales <> String.Empty condition compares the contenst of the input sales variable to the String.Empty value. As you know the String.Empty value represents a zero length, or empty, string if the inputsales variable is empty, the loop condition evaluates to True and the computer process the loop instructions. *If on the other hand the inputsales variable is not empty, the loop condition evaluates to false and the computer skips over the loop instructions.
Based on the code I think it is the opposite: ...that while the inputsales value is not empty it should evaluate to true and process the loop and if it is empty it should evaluate to false and skip the loop?
The problem is that, when it checks that the AbsoluteUri ends with profile it should skip the other 3 commands and make another command (To enable the timer2 at the same time) Is this possible to make this? if yes how?
Role Public Class Role Public Property RoleID As Integer Public Property CreatedBy As User
[code]....
The situation is like when we create roles, we will save who created this role. So i have a CreatedBy Property of type User. Similarly when we create a User, we will mention what role the new user belongs to .So i have a property called "Role" of type "Role". This circular reference giving me StackOverflow exception as its recursive when i create an object of User class.How do i handle this ? should i restucture my entties ? how ?
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I am unable to read a pasted datagridviewrow object from the clipboard. All I want to do is, when a user has the entire row selected and copied, I would paste that row into the clipboard as a DataObject. That works just fine but when I attempt to read that DataObject (after the user clicks Paste) the DataGridViewRow that's saved in the clipboard always has a value of Nothing. Here's the code I'm using for Copy and Paste.
