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Hi,
iam using (ms-access database) with c#..
i have textbox and datagridview control..
i entered "productid" in textbox ,it can fetch the productname,units,cost from database and displayed in datagridview...
2nd attempt:again when i enter "productid",it can also fetch the records and displayed in 2nd row of datagridview...
so i able to see 1st productid details and 2nd productid details...
like that how many times i enter the "productid" in textbox ,that no:of rows displayed in datagridview....
please give me some solution..
murali krishna
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I guess, you want to display only one record on your grid everytime you enter one productid and search for it...right??
if thats the case, then if i assume you are using a dataset object to fill up your grid, you essentially need to re-initialise the grid which you can do by refreshing the Dataset object each time your search code executes.
like you can write
DoSearch()
{
DataSet dsProducts=new DataSet();
//code to fill your grid
dsProducts=null;
}
this way you always have single value in your dataset and hence your grid. I think you can try this, it should work.
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Hi,thanks for reply---
upto this ok..
but when i enter another "productid" in textbox ,the data can be
displayed in another row of the datagridview...
so i can able to see 1st productid details and 2nd productid details
like that how many times i enter "productid" in textbox that no:of rows
created in datagrd view..
murali krishna
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Hi every body,
Any specific procedure is there to identify a active com port.
means if a connect a device to com port, how to identify device is connected to which port.
Thanks
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Hi,
your subject line and message body do not match: what is it you want to identify, the port
to which something is attached, or that something itself?
in any way, it will need some cooperation from the attached device.
Here are the two basic ways to get information:
1. through the control lines
Some devices, when powered and enabled, pull one or several control lines (see SerialPort
properties CDHolding, CtsHolding, DsrHolding)
2. by actually communicating
send commands to the device and look for the responses, if they fit your expectations chances
are the expected device is on the port you are talking to.
If you want to find the port, you probably need to loop over all available ports (see
SerialPort.GetPortNames()
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Good Day,
With recent outbreaks of USB Flash Drive viruses on our campus, I am planning to write a utility that will "Write-Protect" the flash drive. (Since most flash drive here in our country does not come with a "Hardware Switch" to enable the write protection)
Is there any article that will help me to accomplish this task? Or this is fairly impossible?
Thanks,
Ian
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It seems that you don't know how this viruses work!
Even if you find a way to write protect you flash memory, the virus needs you to unprotect it just for a second to write a little thing on it and the virus is there!
In solution of this, I have written a semi anti virus that protect the computer from being infected by infected flash memories and also rescuing the infected flash memory.
As all these viruses infect in the same scenario, my program works well for all even new versions of these viruses.
It is almost finished, but the interface needs a little work.
I will submit my work on codeproject after it was finished.
Sojaner!
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I'll be waiting for that then.
But all I want to know is how to "Write-Protect" the flash drive (Or any other removable media). 
Thanks,
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I'm having 500 hard coded records in a database. Now I thinking about to make a XML for that..So Which one is faster...? A XML file or a database table ..?
If a XML is faster then what is the best way to retrieve the data from it...?
A dataset or make a XML parser for that...? 
Regards
Pankaj Joshi
If you want to shape your dreams into reality, please wake-up...
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If you store all your data in one single xml-file you will have to query wich data to show by using xpath (I guess you wont show all data at once). Another way is to create some xsl-files. But use a database if you can. It's much easier to work with data stored in a database and I think it's faster too.
If this data is static and performance is a big issue you should consider generating static html-files (if it's a webapplication)
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Serverside wrote: If you store all your data in one single xml-file you will have to query wich data to show by using xpath...
Not really. If you use the class XmlDataDocument, you can manipulate XML data through a relational Dataset, so in a similar manner to that used in regular databases.
If there are only 500 records I would recommend either using XmlDataDocument or using an Access database file. The need for a database server like SQL Server or MySql is not justified in such a scenario.
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blackjack2150 wrote: If there are only 500 records I would recommend either using XmlDataDocument or using an Access database file. The need for a database server like SQL Server or MySql is not justified in such a scenario.
What if SQL Server is being used for other data in the application? In that case it becomes a valid candidate. Adding Access to the mix in that scenario would be a very poor idea.
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Database, ie SQL CE.
Faster or not depends on how you use it. Do you load the XML into memory once and use the data from memory? or do you have to query the XML every time? If you load them into memory, you will be hogging a lot of memory.
You won't know if you wake up one day, the requirement has been changed to 6000 records, must be able to add or delete, and changes needs to be deployed to 500 users.
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darkelv wrote: If you load them into memory, you will be hogging a lot of memory.
How do you know? He hasn't said what the 500 records are! It might be 500 IDs with a string value consisting of a few words (lets say 20 chars average). That is 24 bytes (or 44 for Unicode). So that is a whopping 22K. Wow! That's a real memory hungry application.
darkelv wrote: You won't know if you wake up one day, the requirement has been changed to 6000 records, must be able to add or delete, and changes needs to be deployed to 500 users.
Where did he say he had 500 users? And why couldn't the XML file be located in a central location on a network?
You are making a lot of assumptions that were not in the original query. If you are going to do that then you should say that these are your assumptions and therefore they may possibly not apply to the situation.
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Feeling cranky, eh.
That's what the "if" for.
Since he didn't supply more information, I am giving him something to ponder before he decide what he want to do.
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darkelv wrote: That's what the "if" for.
No, it wasn't. You said: "If you load them into memory, you will be hogging a lot of memory." That indicates that you have already made the assumption that the data set is large, not IF the data set is large. I pointed out a fairly reasonable scenario where the data set wouldn't really take that much memory.
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Pankaj - Joshi wrote: I'm having 500 hard coded records in a database. Now I thinking about to make a XML for that..So Which one is faster...? A XML file or a database table ..?
It depends on what you are using these records for. How do you intend to query them? What do they contain?
Pankaj - Joshi wrote: If a XML is faster then what is the best way to retrieve the data from it...?
For example, if the data is a simple key/value lookup then loading it into a Hashtable may be the best thing to do. However, it really depends on what this data is.
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XML is very faster than Database 
Like a good handsome...thanking You
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anandakumarm wrote: XML is very faster than Database
That is a very wide sweeping statement that is incorrect in most scenarios.
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hi,
I have written a pllication using C# and asp.net which set the windows user password using WinNT protocol. It is working fine.
But before setting its password i want to check whether the account is locked or not if account is locked then unlock it.
Plz. give me help how to unlock windows user(2003 server) account using System.DirectoryServices; My code is as below
string entryString = "WinNT://" + Environment.MachineName + ",computer";
DirectoryEntry dirEntry = new DirectoryEntry(entryString);
DirectoryEntry osUser = dirEntry.Children.Find(username, "user");
if (osUser == null)
{
_ErrorMsg = "Such OS user not found.";
}
else
{
if (changepassword)
osUser.Invoke("SetPassword", newpassword);
}
osUser.CommitChanges();
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I had a abstract base class :
namespace ConsoleApplication1
{
public abstract class AbstractClass
{
abstract protected void TestFunction();
abstract internal void TestFunction2();
}
}
Now, I wanted to inherit this class as :
namespace ConsoleApplication2
{
class Client:AbstractClass
{
public Client()
{ }
protected override void TestFunction()
{}
}
}
As the namespace for the above classes are different, we can access the "abstract protected void TestFunction();" in the derived class. But we cannot access and override "abstract internal void TestFunction2();".
Because of this I am getting a compile time error.
How to deal with this problem? Since I want the internal method as it is and still want to compile the application.
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Mukesh Choudhari wrote: we cannot access and override "abstract internal void TestFunction2();".
Internal methods can't be accessed outside the assembly. It can be accessed in the same assembly. Consider moving it to the same assembly.
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Yes it worked when I moved it to same assenbly.
But what if I had this class in a DLL and I am using this DLL in some other project. Now since the class has a "internal abstract" member in it, I won't be able to inherit this class.
Is there any other way that we can inherit this class and it will not ask for overriding the "internal abstract" method?
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Mukesh Choudhari wrote: Is there any other way that we can inherit this class and it will not ask for overriding the "internal abstract" method?
Only method I am getting is making the second class as abstract too.
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