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My database is already having appropriate indexes and primary keys wherever suitable. The old application was built in VB6. I need to port my VB6 code to VB.NET.
My biggest concern still remains.
The classic ADO had the SEEK method that could utilize the indexes and get very fast results. I tried various ADO.NET methods, but nothing gets even near to the speed I was getting earlier. My application has bogged down and has raised a big concern.
I was wondering if there is any way in ADO.NET to utilize the indexes in database?
Please help.
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Normally you would do this is the query itself. This is where I am not very certain what you can do in access. In sql you can just write the query. Select column1, column2, etc from table where column1 = 'fred'
If column1 is index that query is very fast. I am just not sure if you can do this. If you can it would be with a sqlCommand object. You would set the commandtext to the query and then call the executereader to return the result set.
Again my issues is I have never tried to do this with Access. I think it will work since access has a very similar sql engine, but I don't know exactly how.
Hope that helps.
Ben
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I have been a classic ASP and Visual Basic 6.0 programmer for some time. My company went belly up and now I am unemployed. I want to stay in my home town.
All the jobs that are available all want 1-3 years of .NET experience. This is rediculious. Is it some kind of way to keep the old guys out of the market.
Come on, I use to program mail frame, and taught myself the PC area.
Does anyone know how to break thru the gate, get pass the palace guard? I have read a good number of books on the subject. Loaded up MS .NET Framework on my PC. And written a few programs/systems.
Anybody have any helpful suggestions>
Chuck 
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I passed through the same situation and can understand your grief.
Come to the ground situation and start believing that VB6 and ASP are history now.
Take my suggestion and get a good book on VB.NET and ASP.NET today itself and start working hard. Or take some good tution from some good institute. It would be hardly a matter of 3 to 6 months before you get back on to the track.
Good Luck ![Rose | [Rose]](https://codeproject.freetls.fastly.net/script/Forums/Images/rose.gif)
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chuckd0138 wrote: All the jobs that are available all want 1-3 years of .NET experience. This is rediculious.
Welcome to the world of IT recruitment. It will always be this way. Consequently there will always be "skills shortages." (Though in this particular case companies can find plenty of people who meet this spec.)
chuckd0138 wrote: Is it some kind of way to keep the old guys out of the market.
To some extent. For example, occasionally you will see jobs advertised that are more relaxed in their skills requirements and perhaps offer cross-training. But the salaries will be low and/or they will be aimed at graduates with a few years' general commercial experience.
Basically, in this industry I've discovered that the older you get the more important it is to acquire commercial experience in the latest skills, whether you want to or not.
chuckd0138 wrote: Does anyone know how to break thru the gate, get pass the palace guard? I have read a good number of books on the subject. Loaded up MS .NET Framework on my PC. And written a few programs/systems.
Just keep on doing what you are doing. Also try applying it to a web site or something and then put it on your Resume. Eventually someone will give you a chance. I've been where you are (and I'm an "older guy" too) . It's frustrating but hang in there.
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If you are really serious about getting into vb.net asp.net then I suggest you try to get some microsoft certification. Something like the MCAD.net or MCSD.net. The MCAD.net is for .net 1.1 and there are three required tests. The MCSD.net includes the 3 MCAD.net tests along with two addional tests. If you can achieve that certification, then you can go into a job interview and say hey I have the certification and I am building my experience.
NOTE these tests are not easy to pass and require a lot of study. The tests are cheap either $125 a test. Also the processes can be long it took me a good 6 or 7 months to pass all 5 tests.
NOTE there are newer certification for .net 2.0. I have found these tests to be even harder then the 1.1 tests.
Hope that helps.
Ben
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How can i make trial version in vb.net?
................
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Socheat.Net wrote: How can i make trial version in vb.net?
A bit vague...
Maybe a better approach will be:
"I have an application as follows [..], I would like to build a trial version that includes/escludes the following functionalities [...], the trial has/hasn't to expire after some time...."
BTW Google is often you best friend.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
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Pseudocode:
If now > expiration date
msgbox("Expired!")
me.close()
End If
Or, if you want to make it expire after X number of days, use my.settings...
'load event
if my.settings.CreateDate = Nothing then
my.settings.CreateDate = now
elseIf my.settings.CreateDate - now > X 'X being how long the trial period should last
msgbox("Expired!")
me.close()
else
'Your code here
end if
Don't use this exact code! It's not secure (so especially don't use it for anything important) and you should know how it works.
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Thanks in advance
................
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Hi! Give me please example for Response.Cache.SetETag(“????”)
Are other words, what string I have gone set to SetETag?
In order to return code 200 or 304.
-- modified at 7:27 Tuesday 3rd April, 2007
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After a long time searching...
After so many mouse-click...
Surfed so many pages
I think it is ok to work as a global hook but it doesn't work.
I don't know where the problem is.
Here is my steps:
1.open a new windows aplication project.
2.add a module with code below
<br />
Module Module1<br />
Declare Function GetCurrentThreadId Lib "kernel32" Alias "GetCurrentThreadId" () As Integer<br />
Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Integer, ByVal lpfn As HOOKPROC, ByVal hmod As Integer, ByVal dwThreadId As Integer) As Integer<br />
Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Integer) As Integer<br />
Declare Function CallNextHookEx Lib "user32" Alias "callnexthookex" (ByVal hHook As Integer, ByVal ncode As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer<br />
<br />
Public Delegate Function HOOKPROC(ByVal nCode As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer<br />
<br />
Private Declare Function GetAsyncKeyState Lib "user32" (ByVal vKey As Integer) As Integer<br />
<br />
Public hnexthookproc As Integer = 0<br />
<br />
Public Const PM_KEY_PrintScreen = &H2c<br />
<br />
Public Structure KbStruct<br />
Dim vkCode As Integer<br />
Dim ScanCode As Integer<br />
Dim Flags As Integer<br />
Dim Time As Integer<br />
Dim dwExtraInfo As Integer<br />
End Structure<br />
<br />
Public Enum HookType<br />
<br />
WH_KEYBOARD = 2<br />
<br />
End Enum<br />
<br />
Public Sub UnHook() 'close Hook <br />
If hnexthookproc <> 0 Then<br />
UnhookWindowsHookEx(hnexthookproc)<br />
hnexthookproc = 0<br />
End If<br />
End Sub<br />
<br />
Public Function SetHook() 'set Hook <br />
If hnexthookproc <> 0 Then<br />
Exit Function<br />
End If<br />
<br />
hnexthookproc = SetWindowsHookEx(HookType.WH_KEYBOARD, AddressOf MyKeyboardProc, 0, GetCurrentThreadId())<br />
End Function<br />
<br />
<br />
Public Function MyKeyboardProc(ByVal nCode As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer<br />
MyKeyboardProc = 0<br />
If nCode < 0 Then<br />
MyKeyboardProc = CallNextHookEx(hnexthookproc, nCode, wParam, lParam)<br />
Exit Function<br />
End If<br />
<br />
If wParam = PM_KEY_PrintScreen Then<br />
MyKeyboardProc = 1<br />
MsgBox("HOOK！")<br />
End If<br />
End Function<br />
End Module<br />
3.call my function to set hook in form_load and close in form_close:
<br />
Public Class Form1<br />
<br />
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load<br />
Call SetHook()<br />
End Sub<br />
<br />
Private Sub Form1_FormClosed(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles Me.FormClosed<br />
Call UnHook()<br />
End Sub<br />
<br />
End Class<br />
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The possible problems are:
(1) a global WH_KEYBOARD hook must reside in a standard old style (not .NET) dll because that dll has to be loaded in to the address space of each and every running application. If you want this kind of functionality from a VB/VB.net app you should use the WH_KEYBOARD_LL hook instead.
(2) A message box will only be shown if the app that gets the key press is the foreground app which might not be the case.
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Thanks for your answer.I will try it out and post the result.
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http://sean.o4u.com/ap/calendar/calendar.htm[^]
This link above is a Chinese calendar. If you move mouse to any day on the calendar, it will pop up some informations about Chinese.
This page can be downloaded.
I have question that...is there any method to grab the pop up information of this page? I wite a windows form and I hope I can do this.
Can any one help me?
thanks very much.
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No, there isn't. Java isn't rendered using Win32 windows. There are no window handles to grab and, hence, no way to talk to that window to get at it's information. It is, quite literly, a picture that looks like text.
Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007
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first of all i am not sure, that this is the right place. Since I did not find any place to place my question regarding an excel macro, I am using this place because the macro is being written using VB.
Consider a case, where I am opening an existing excel file that has filters. If I want to disable/remove/delete the filters, how can I can i do it in the same macro.
Thanks.
Keshav Kamat
India
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need help in crystal report.....,
take sample like this....,
In table i have collections of students marks based on studentid....,
i displayed based on the studentid his grandtotal and some other calculations in my form,
Now what are the output i am getting in my form,those things i want to display in crystal report also...,
how to pass thos evalues to my crystal report.....
plz help me...
-- modified at 3:13 Monday 2nd April, 2007
Magi
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create parameters in your crystal reports and pass them values from your form like:
u need the following classes to pass parameters:
Imports CrystalDecisions.crystalreports.engine
Imports CrystalDecisions.reportsource
Imports CrystalDecisions.shared
Imports CrystalDecisions.windows.forms
import them like so...then: in your code
private sub ViewReport()
Dim yourReport As New Report ''create an instance of ur crystal report
'Dim crParameterDiscreteValue As ParameterDiscreteValue
'Dim crParameterFieldDefinitions As ParameterFieldDefinitions
'Dim crParameterFieldLocation As ParameterFieldDefinition
'Dim crParameterValues As ParameterValues
'crParameterFieldDefinitions = rep.DataDefinition.ParameterFields
'crParameterFieldLocation = crParameterFieldDefinitions.Item("ParamenterNameInReport")
'crParameterValues = crParameterFieldLocation.CurrentValues
'crParameterDiscreteValue = NewCrystalDecisions.Shared.ParameterDiscreteValue
'crParameterDiscreteValue.Value = "Your parameter value"
'crParameterValues.Add(crParameterDiscreteValue)
'crParameterFieldLocation.ApplyCurrentValues(crParameterValues)
CrystalReportViewer1.ReportSource = YourReport
end sub
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Hello
I wrote the web page with VB.net (web application) and pages work fine, but back button of the IE browser does not work ? Clicking the back button at my homepage does not open the earlier pages. But in Firefox everything works fine. How do I get project work also in Internet Explorer.
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Hi,
I want to access database which is kept on website database folder.
Anybody could help me please? How to connect this database? What should be
connectionstring for it with detail code? i am developing it in Vb.net 2005.
I am beginer for vb.net.
Kiran Sajanikar
Software Engineer
Pune.
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Hi,
Have a look at THIS[^]
Mubashir
Every job is a self portrait of the person who did it.
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Thanx For your immediate reply.
I used that code.
But it is giving error:
The error is:
---------------------------------------------------------
System.Runtime.InteropServices.COMException was unhandled
Error code=-2146819841
Message="Internet Server Error"
Source="Microsoft ADO/RDS"
---------------------------------------------------------
The Error occured while opening the recordset.
Please give me solution for this.
I have used the same code as per that article.
Waiting for your reply
Kiran Sajanikar
Software Engineer
Pune.
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I'm using Visual Basic 4.0 ( Unable to upgrade for reasons, to lengthy to describe )
and I'm having trouble generating sound frequencies. What I'm hoping for is to find
some sort of code solution or tips, advice on this.
A simple VB form, with a text box on it, a command button and the relevant code would be sufficient, thanks!
There are two main things I'd like to be able to do, but I'd be happy to come across solutions for either.
First;
I have an application that generates a series of numbers and then dumps these to a text file. The numbers are hertz fequency values to four decimal places. The text file will generally be comma delimited, in a format similiar to;
432.1298
256.9887
333.99
2445.77
and so on....
A text file may contain as little as eight numeric frequency values or up to three thousand.
What I want to do, is feed this text file of numbers into some sort of music generating tool, convert these numbers into actual musical frequencies and store these files as avi, mpeg, wav files, whatever. If I coudl do this in code without having to use a dedicated musical software program that would be great, but I'm open to other sorts
of solutions too.
I'd like to be able to set the time duration for how long each note in the file is played for, i.e. all note are played for 120 seconds, etc....
A 'nice' thing to do also possibly, would be to choose some sort of instrumental sound, like chimes, flute, etc as the instrument the frequencies are to be played on.
Secondly;
I want to specify exact frequencies for play back, NOT just preset values for specific tones, such as one base freq for a given note, its sharp or flat.
Want to play musical notes but NOT just on PC Speaker.
What I'm hoping to figure out;
-Allow any numeric value for frequency in hertz in the format of 888.88 as input into text box for VB application
-Value of frequency in textbox saved to a variable
-Variable passed to relevant routine or ocx component
-Routine or component plays back specific tone frequency on Sound Card (Not PC Speaker)
-Playback allows volume adjustment
I just need something basic and simple to play with to see if it will work for me, all I need is for the sample code to; Allow any numeric value in the format of 888.88 as input into text box
Value in textbox saved to a variable Variable passed to relevant component. Component plays back specific tone frequency Playback allows volume adjustment
==============
I've received a lot fo different tips and advice on how to do all this but nothing that meets all the requirements, i.e.
Hi,
I've seen your software online and noticed you were using something called MMTools to play sounds with.
I just need something basic and simple to play with to see if it will work for me, all I need is for the sample code to; Allow any numeric value in the format of 888.88 as input into text box
Value in textbox saved to a variable Variable passed to relevant component. Component plays back specific tone frequency Playback allows volume adjustment
I've listed some of the things I've already tried below and described why these won't work, and in summary they are;
BeepAPI
How to Emulate QuickBasic's SOUND Statement in Visual Basic
midiOutShortMsg and related
===============
Problem with MIDI;
Also, I love this method, but after reading all the info it looks like it won't actually let me specify exact frequencies for play back, only preset values for specific tones, such as one base freq for a given note, its sharp or flat.
Knowing how to do this is valuable in and of itself, I now can play back musical notes that sound a lot better than the PC Speaker sounds. Sadly this doesn't solve the problem I have though.... 
create wav file
--------------------------------------------------------------------------------
The following code works but won't let me specify exact frequencies, only tones
This generates a wave file (no clicks or ticks... just clear sound ):
(It makes a 1 second tone of 440 Hz)
VB Code:
Option Explicit
Private Type tWAVEFORMATEX
wFormatTag As Integer
nChannels As Integer
nSamplesPerSec As Long
nAvgBytesPerSec As Long
nBlockAlign As Integer
wBitsPerSample As Integer
cbSize As Integer
ExtraData(1 To 32) As Byte ' makes the structure 50 bytes long
End Type
Private Type FileHeader
lRiff As Long
lFileSize As Long
lWave As Long
lFormat As Long
lFormatLength As Long
End Type
Private Type WaveFormat
wFormatTag As Integer
nChannels As Integer
nSamplesPerSec As Long
nAvgBytesPerSec As Long
nBlockAlign As Integer
wBitsPerSample As Integer
End Type
Private Type ChunkHeader
lType As Long
lLen As Long
End Type
Private Sub Form_Load()
Dim Buff(0 To 44100) As Integer
GenerateTone 440, Buff, 1
SaveWaveFile "C:\test_Wave.wav", Buff
End Sub
Private Sub GenerateTone(ByVal Frequency As Single, IntBuff() As Integer, Optional Amplitude As Single = 1, Optional SamplesPerSec As Long = 44100, Optional Startpos As Long = 0, Optional Length As Long = -1)
Dim K As Long, V1 As Double
Const PI As Double = 3.14159265358979
V1 = SamplesPerSec / (PI * 2 * Frequency)
If Length = -1 Then Length = UBound(IntBuff) - Startpos
For K = Startpos To Startpos + Length
IntBuff(K) = CInt(Fix(Sin(K / V1) * (32766.5 * Amplitude)))
Next K
End Sub
Private Sub SaveWaveFile(ByVal WaveFileName As String, ByRef Buffer() As Integer, Optional SamplesPerSec As Long = 44100)
Dim WF As tWAVEFORMATEX
WF.wFormatTag = 1 'WAVE_FORMAT_PCM
WF.nChannels = 1
WF.wBitsPerSample = 16
WF.nSamplesPerSec = SamplesPerSec
WF.nBlockAlign = (WF.wBitsPerSample * WF.nChannels) \ 8
WF.nAvgBytesPerSec = WF.nSamplesPerSec * WF.nBlockAlign
Open WaveFileName For Binary Access Write Lock Write As #1
WaveWriteHeader 1, WF
Put #1, , Buffer
WaveWriteHeaderEnd 1
Close #1
End Sub
Private Sub WaveWriteHeader(ByVal OutFileNum As Integer, WaveFmt As tWAVEFORMATEX)
Dim header As FileHeader
Dim HdrFormat As WaveFormat
Dim chunk As ChunkHeader
With header
.lRiff = &H46464952 ' "RIFF"
.lFileSize = 0
.lWave = &H45564157 ' "WAVE"
.lFormat = &H20746D66 ' "fmt "
.lFormatLength = Len(HdrFormat)
End With
With HdrFormat
.wFormatTag = WaveFmt.wFormatTag
.nChannels = WaveFmt.nChannels
.nSamplesPerSec = WaveFmt.nSamplesPerSec
.nAvgBytesPerSec = WaveFmt.nAvgBytesPerSec
.nBlockAlign = WaveFmt.nBlockAlign
.wBitsPerSample = WaveFmt.wBitsPerSample
End With
chunk.lType = &H61746164 ' "data"
chunk.lLen = 0
Put #OutFileNum, 1, header
Put #OutFileNum, , HdrFormat
Put #OutFileNum, , chunk
End Sub
Private Sub WaveWriteHeaderEnd(ByVal OutFileNum As Integer)
Dim header As FileHeader
Dim HdrFormat As WaveFormat
Dim chunk As ChunkHeader
Dim Lng As Long
Lng = LOF(OutFileNum)
Put #OutFileNum, 5, Lng
Lng = LOF(OutFileNum) - (Len(header) + Len(HdrFormat) + Len(chunk))
Put #OutFileNum, Len(header) + Len(HdrFormat) + 5, Lng
End Sub
===========
===========
This code works, but only allows me to generate sounds to the PC Speaker, which sounds horrible!
Option Explicit
Private Declare Function Beep Lib "kernel32.dll" (ByVal dwFreq As Long, ByVal dwDuration As Long) As Long
Private Sub Command1_Click()
Beep 432.8765, 1000
End Sub
================
=========================
This code works for MIDI, but doesn't let me specify exact frequencies only preset musical tones
==================
midiOutShortMsg
The midiOutShortMsg function sends a short MIDI message to the specified MIDI output device.
VB4-32,5,6
Declare Function midiOutShortMsg Lib "winmm.dll" (ByVal hMidiOut As Long, ByVal dwMsg As Long) As Long
Operating Systems Supported
Requires Windows NT 3.1 or later; Requires Windows 95 or later
=============
PLAY NOTE:
Private Declare Function midiOutClose Lib "winmm.dll" (ByVal hMidiOut As Long) As Long
Private Declare Function midiOutOpen Lib "winmm.dll" (lphMidiOut As Long, ByVal uDeviceID As Long, ByVal dwCallback As Long, ByVal dwInstance As Long, ByVal dwFlags As Long) As Long
Private Declare Function midiOutShortMsg Lib "winmm.dll" (ByVal hMidiOut As Long, ByVal dwMsg As Long) As Long
Dim hMidiOut As Long
Private Sub Form_Load()
'KPD-Team 2000
'URL: http://www.allapi.net/
'E-Mail: KPDTeam@allapi.net
Dim T As Long
midiOutOpen hMidiOut, 0, 0, 0, 0
midiOutShortMsg hMidiOut, 6567325
T = Timer
Do: DoEvents: Loop Until Timer > T + 4
midiOutClose hMidiOut
End Sub
----------------------
http://allapi.mentalis.org/apilist/midiOutShortMsg.shtml
===============================
Again, this only works for the PC Speaker
A better beep
If you aren't satisfied with the standard Beep command (who is?) you can use the Beep API function instead, that lets you control both the frequency (in Hertz) and the duration (in milliseconds) of the beep. Note that you need an aliased Declare to avoid a name conflict with the VB command:
Private Declare Function BeepAPI Lib "kernel32" Alias "Beep" (ByVal dwFrequency _
As Long, ByVal dwMilliseconds As Long) As Long
The standard Beep command has a frequency of 440 Hertz and a duration of 200 milliseconds (more or less), so you can produce a short beep with a higher pitch with the following statement:
BeepAPI 600, 100
And of course you can even produce more complex sounds, when a simple beep won't suffice:
Dim i As Long
For i = 100 To 1000 Step 10
BeepAPI i, 20
Next
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