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Hi all,
I am trying to come up with a way of securing controls inside of a VB.NET 2005 windows form application. I have searched online and found information, but they are all base on ASP.NET - which I think the usage, codes and all differ to quite some degree from VB.NET (Codeproject's article are also not useful enough, like http://www.codeproject.com/KB/vb/2gs_txtbx.aspx#add[^], which is not really what I want)
I have created database to store usernames and passwords. And, I have already did a login form which can verify the username and password submitted (if both values are correct, the user would be directed to another form).
1) How to set user groups, e.g admin and user. I would want to have two level of security. One that has limited access to certain forms (users) and another that has full access (admin).
2) And also if possible, I would like users to be able to access a form with controls such as DataGridView (using Dataset) but not be able to edit them.
Is there any good concepts out there (or codes in particular, is it a code thing or?) on how to manage this efficiently?
Any help would be greatly appreciated. Thanks!
telly
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I'd like to populate a rich text box control with text from a number of records from an SQL database.
The text from each record will be protected and unable to be edited by the user. For ease of reference I'll refer to this as Protected Text.
However, the user can enter text after each section of Protected Text. This text is (in effect) appended to the record in the SQL database. I'll refer to this as User Text.
I then need to be able to parse the rich text box control, going to each segment of Protected Text, retrieving the record ID associated with the Protected Text then write User Text to the database using the record ID.
Does anyone have any idea how to do this?
I understand the Selection Protected property of the rich text box control. What I'm struggling with is
- how to embed the record ID in the rich text box at the appropriate point
- how to parse the rich text box retrieving the record ID and User Text.
Any assistance would be much appreciated.
Thanks in advance
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I am a middle aged internet college student trying to get some assistance a Case problem for my course. I have ask for help from instructor, but due to the holidays he has not replied to any of my queries. My assignment is due no later midnight on the 28 of Dec 07. I am stuck like chuck...
Project Name: Random Number Game
Scope: Create an VB.Net app that allows the user to guess a random number generated by the computer. When the user makes an incorrect guess, the application should move an image up or down depending on how the guess compares to the random number. If the random number is greater that users guess the image shoould move upwards to indicate to the user to guess higher. Same with a lesser guess but the image moves lower indcate the user shoul guess lower. The game ends when the user guesss the random number. If the usershould opt to end the game early the random number should be displayed.
I have been able to create a text indicator version of this game without the early termination criteria. I have come to an impass. Snippet of code of functioning code below:
---------------------------------------
Option Strict On
Option Explicit On
Imports System.Globalization
Public Class mainForm
Private Sub startButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles startButton.Click
Dim randomGenerator As New Random
Dim inputString As String
Dim input As Integer
Dim random As Integer
Dim isConverted As Boolean
Const Prompt As String = "Enter guess"
Const Title As String = "Guess a number"
'Dim cancel As DialogResult = Windows.Forms.DialogResult.Cancel ' Case usage
'Dim ok As DialogResult = Windows.Forms.DialogResult.OK ' Case usage
'Dim choice As DialogResult
' primer read - not needed program work fine without it
'input = 0
'generate random number from 1 t0 10
random = randomGenerator.Next(1, 11)
' Begin Loop
Do
'input guess
inputString = InputBox(Prompt, Title, "0")
'Select Case choice
' Case Windows.Forms.DialogResult.Cancel
'If Windows.Forms.DialogResult.Cancel = cancel Then
'input = random
'MessageBox.Show("The number was " & random, "Answer", MessageBoxButtons.OK)
'End If
' Case Windows.Forms.DialogResult.OK
'If Windows.Forms.DialogResult.OK = ok Then
isConverted = Integer.TryParse(inputString, input)
If isConverted = True Then
'if input is integer then execute loop
If input > random Then
displayLabel.Text = "Guess lower"
ElseIf input < random Then
displayLabel.Text = "Guess Higher"
Else : input = random
displayLabel.Text = random & " is correct"
End If
Else
MessageBox.Show("Enter a number between 1 and 10")
End If
'End If
'End Select
'End Select
Loop Until input = random ' End Loop
'-----------------------------------------------------------
'display correct guess
'If input = random Then
'MessageBox.Show("You are correct") 'alternate method of correct guess display
'displayLabel.Text = random & " is correct"
'End If
End Sub
End Class
You will notice that I remarked out my all my Case structure, when I add them the program ceases to function properly. Any help would be appreciated, I have waited to the last minute because I thought I woulde get the help I needed from my instructor. Thanks in advance to any who care to respond. 
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Are you asking about the case thing only or are you having other problems? Also we would be able to help you better if you gave us some of the error messages you are getting and what lines are coming up as bad.
One thing that I see is that you have 2 end selects commented out and I only see one select case statement. On top of that one would be nested inside the other which I doubt was your intent.
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Thanks for the reply,
When I add the case statments the app gets stuck in the loop for some reason. There are no error messages. The program will not display the "guess higher" or "guess lower". In addition it will not perform its data validation. It just keeps displaying the inputBox. I thought maybe I coded the event arguement for the Cancel and OK incorretly, but I cant find anything in my book(Microsoft Visual Basic 2005: Reloaded, Second Edition).
I apoligize for th sloppy code. I have been hash at it for the last week. I even toyed with methods of input(listbox and combobox). The input box just facilitates input for a Loop. My frustration maybe getting the better of me.
The code works as is, but when I hit the cancel button from the input box I keep getting the data validation message, which prompted me to use the case statement.
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I think I understand what is wrong here but please let me know if my guess about your intentions is incorrect.
It looks like you're drawing a false analogee between how c/c++ handles events and how vb handles events. There is no reason I can see that you would need a loop at all and it looks like you are trying to treat your subroutine as if it was main in c/c++. In c/c++ execution starts at main and events are handled one of 2 ways: either there is an infinate loop that is interrupted with an interrupt or you use some library function that stops execution. For instance scanf will stop and wait for you to make an input.
VB doesn't work that way. Nothing that I am aware of waits for inputs and there is no main. It looks like you are expecting your inputbox to work like a scanf. What will happen in vb is that the program will immediately read your inputbox then go immediately to the next line of code regardless. Everytime you do something vb looks for a subroutine that matches the event and if it finds one it call that sub and goes till it finishes execution. In general I think you are making your code way more complicated than it needs to be.
Lets get specific, you are getting an infinate loop it looks like because it looks like the assignment of random to input probably never executes because it is nested in a case that never executes. Therefore your loop always test something other than random. But to be honest I don't think you need a loop at all.
I might be misunderstanding your project cause I don't understand the logic of some of your code. But if I am understanding it correctly I would do it like below.
dim inputnum as integer, randomnum as integer<br />
<br />
'create a random number<br />
inputnum = textbox1.text<br />
if inputnum > randomnum then<br />
'move picture up<br />
elseif inputnum < randomnum then<br />
'move picture down<br />
else 'they're equal<br />
'game is done<br />
end if
ps if you have option strict on you may need to do some casting on this statement inputnum = textbox1.text but I'm not sure.
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Mike, Thanks for the help. I thought I may have been over complicating things. I will try it out and see what happens. Thanks again.
DK
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Mike, Thanks for getting me to simplify things. I have a solution that meets the criteria. Unfortunatly it does not use the principals outlined in the chapter I am working on (Decisions and Loops). I have posted my solution below:
Option Strict On
Option Explicit On
Public Class mainForm
' declare variable for form
Dim random As Integer
Private Sub mainForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'declare variable
Dim randomGenerator As New Random
'generate random number and direct focus to text box
random = randomGenerator.Next(1, 11)
inputTextBox.Text = "0"
inputTextBox.Focus()
End Sub
Private Sub startButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles startButton.Click
' decalre variables
Dim randomGenerator As New Random
Dim input As Integer
Dim isConverted As Boolean
'convert input and validate input
isConverted = Integer.TryParse(inputTextBox.Text, input)
If isConverted = True Then
'direct focus to text box
inputTextBox.Clear()
inputTextBox.Text = "0"
inputTextBox.Focus()
' Decision Tree
If input > random Then
pointPictureBox.SetBounds(82, 162, 100, 50)
displayLabel.Text = "Last Guess was " & input
input = 0
inputTextBox.Focus()
ElseIf input < random Then
pointPictureBox.SetBounds(82, 82, 100, 50)
displayLabel.Text = "Last Guess was " & input
input = 0
inputTextBox.Focus()
Else
pointPictureBox.SetBounds(82, 122, 100, 50)
displayLabel.Text = random & " is correct"
End If
Else
' if invalid iput then show
MessageBox.Show("Input Number from 1 to 10")
End If
End Sub
Private Sub exitButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles exitButton.Click
'Show Random and Close Application
MessageBox.Show("The number was " & random, "Answer", MessageBoxButtons.OK)
Me.Close()
End Sub
Private Sub newButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles newButton.Click
' Generate random number and direct focus to text box
Dim randomGenerator As New Random
random = randomGenerator.Next(1, 11)
inputTextBox.Focus()
End Sub
Private Sub Label1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label1.Click
End Sub
End Class
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Well I'm glad I was able to at least partially help you. I'm not sure what to tell you now though since I probably don't have your book I can't really help you to make it conform with the book.
good luck
Mike
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Hi,
As the title says?
How?
I tried with
button.image = image.fromfile(image.ico)
...
doesn't work
thanks
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try
add the icon files to the application resources then
button.image = my.resource.iconfilename
help everyone
Falling down is not defeat...defeat is when u refuse to get up...
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unix_master01 wrote: doesn't work
What is not working? You have to describe better than that. No image? Exception? What?
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
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Hi,
you can take Imagebutton and give imageURL = "your ico file"
 simple
Thanks,
Sun Rays
To get something you must have to try once.
My Articles
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hi all i am working on a project that will store and display and print yellow pages.
please suggest me what control should i use to get it done.
i am not interested in crystal report.
my requirement is to display the print the whole data in database in less time as possible.
some body has any idea.
help everyone
Falling down is not defeat...defeat is when u refuse to get up...
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Use the PrintPreviewdialog if you want to print something not allready on the screen, otherwise use the printform control, you can download it from microsoft. It's in the vb.net powerpack.
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i need the code for login to windows using VB.NET2003????
for example, when your computer is standby and you want to login again while program is running
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1. Do not cross post.
2. Give your message titles some meaning. We don't care if it's urgent or you need help.
3. We are not just going to hand over code to you. Either search for it, or write it yourself.
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leckey wrote: Current Rant: "Sally Field Must Die!"
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
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Thanks for pointing that out--I need to update it!
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Hi,
I have made a custom control, the control has only 1 textBox and one button.
But i can't show the control in normal way .show() . I need to show the control in a panel so i'm using this code:
If treeView1.Nodes.Item("nodeTarife").IsSelected Then
Dim k As New conTarife ' this is the custom control
SplitContainer1.Panel1.Controls.Add(k)
k.Show()
End If
What am I doing wrong?
Thanks!
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From the code you've posted, you haven't done anything wrong. You really should even need the Show line. The only thing I can think of, without blaming anything on the control itself, is that Panel1 of the SplitContainer is hidden on the left side of the Split.
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Cannot open View Designer in Visual Studio.And My View Designer show this
Message!!!!!
Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
Hide
at System.RuntimeType.InvokeDispMethod(String name, BindingFlags invokeAttr, Object target, Object[] args, Boolean[] byrefModifiers, Int32 culture, String[] namedParameters)
at System.RuntimeType.InvokeMember(String name, BindingFlags bindingFlags, Binder binder, Object target, Object[] providedArgs, ParameterModifier[] modifiers, CultureInfo culture, String[] namedParams)
at System.ComponentModel.Design.Serialization.CodeDomSerializerBase.DeserializeExpression(IDesignerSerializationManager manager, String name, CodeExpression expression)
at System.ComponentModel.Design.Serialization.CodeDomSerializerBase.DeserializeStatement(IDesignerSerializationManager manager, CodeStatement statement)
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Does this happen on any other machine you might have around? Sounds like potential for bad memory.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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Please, Help me if anybody can!!!!!
I want to generate own Report from my project,not from Crystal report Software.
I used following control in VB6 to generate Crystal.
CRViewer.This control can get Crystal Report Viewer component.
Like this VB6 code,i am using this control in VB.Net,
Friend WithEvents crvReport As CRVIEWERLib.CRViewer
Me.crvReport = New CRVIEWERLib.CRViewer
And my form has Preview command button to preview own report from this form.If user click this Preview button ,user can preview his own report.For
this ,i am using this code in cmdPreview_Click().
Call frmpReport.ShowReport(m_astrType, m_strColumn, m_aintWidth, m_astrFSource, blnSave)
,but my project face with problem in this line.
Call frmpReport.ShowReport(m_astrType, m_strColumn, m_aintWidth, m_astrFSource, blnSave)
Error Message is
Unable to cast COM object of type 'CRVIEWERLib.CRViewerClass' to interface type
I will waiting for your answer.THANKS For ur Answer.
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You posted this same thing the day before. Obviously, no one has a solution for you.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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