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Re: Insert a char in the beginning of the file using c#

2-Mar-09 1:22

Member 578189 wrote:
I need to insert a char in the beginning of the XML file. Char is “?”.

If you insert ? to the beginning of XML file, XML file will become invalid and you will not be able to parse it. Are you trying to add the <?xml version="1.0" encoding="utf-8" ?> line?

Navaneeth

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Member 5781892-Mar-09 2:51

Member 578189

2-Mar-09 2:51

Navaneeth,
my original line is
and i need ?<xml version="1.0" encoding="utf-8">;

small background about what i am doing:
I am creating a xml file in console and trying it save it as XML.
And when i use this XML it gives me an error because char "?" is missing.

Re: Insert a char in the beginning of the file using c#

N a v a n e e t h2-Mar-09 15:33

2-Mar-09 15:33

Member 578189 wrote:
I am creating a xml file in console and trying it save it as XML.

Use the XML manupulation classes like XMLDocument. It has got a Save method which writes a XML file.

Navaneeth

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Insert record

Sajjad Leo2-Mar-09 1:05

Sajjad Leo

2-Mar-09 1:05

Dear All,

i am using DataRow for insert update query for records in c# and this error below what should i do?

Update requires a valid Insert Command when passed DataRow collection with new rows

what i have to do for insert record ?
Is this is good approach to insert and update data in tables.

Kindly brief me.

Sajjad Lashari

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Colin Angus Mackay2-Mar-09 2:29

Colin Angus Mackay

2-Mar-09 2:29

Sajjad Leo wrote:
what i have to do for insert record ?

Follow the instructions in the error message. You need to create an Insert command on the SqlDataAdapter.

Sajjad Leo wrote:
Is this is good approach to insert and update data in tables.

In my opinion? No, never.

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Sajjad Leo2-Mar-09 17:50

Sajjad Leo

2-Mar-09 17:50

Hi Dear,

You replayed good but i am still not able to get my goal,
can you guide me if i am inserting a record what steps should i follow please send me complete steps.

Sajjad

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Colin Angus Mackay2-Mar-09 21:35

Colin Angus Mackay

2-Mar-09 21:35

Sajjad Leo wrote:
please send me complete steps

You have not sent me complete detail of what you are wanting inserted and where.

Basically, create a SqlConnection object, create a SqlCommand object, Open the connection, ExecuteNonQuery on the command object and then Close the connection.

Your command should preferably use stored procedures in the database.

Vogon Building and Loan advise that your planet is at risk if you do not keep up repayments on any mortgage secured upon it. Remember that the force of gravity can go up as well as down.

Limiting maximum connections

Sajjad Leo2-Mar-09 23:13

Sajjad Leo

2-Mar-09 23:13

Dear,

I solved that problem now i using a sql query for retrieving a record from a student table i am selecting class from drop down like Class A and then the data of class A name of students will display in list box and then i select one name of class A from list box and want to display data in grid view i am writing query like

string rec = "select * from student_biodata where student_name = '" + liststudent.Text + "' ";

But one problem is that if i am selecting name like 'a' then two record displayed in grid view like 'a' of class A and 'a' of Class B so what should i do please guide me correct query as i can get only one record.

Thanks

Sajjad Ali

modified on Tuesday, March 3, 2009 5:22 AM

invader822-Mar-09 1:00

2-Mar-09 1:00

What is the best method if I want to limit The number of connections a server accepts?
I suppose this is not really a good way to achieve what i want:

while(true)
{
	if(numberOfConnections < 100)
	{
		Socket s = listenerSocket.Accept();
		...
	}
	else
	{
		Thread.sleep(1); //or Thread.sleep(0);
	}	
}

Has anyone a better idea how to keep the cpu down?

harold aptroot2-Mar-09 1:09

harold aptroot

2-Mar-09 1:09

I's probably use a ManualResetEvent instead of sleeping a thousand times per second - it's more accurate and less of a hack.

ManualResetEvent m = new ManualResetEvent(true);
while(true)
{
	m.WaitOne();
	if(numberOfConnections < 100)
	{
		Socket s = listenerSocket.Accept();
		...
	}
	else
	{
		m.Reset();
	}	
}

And somewhere at a place where you close the connections, do m.Set() if the number of connections is lower than 100 again.

But beware, I just woke up, so don't trust this code or even this idea Smile | :)

Luc Pattyn2-Mar-09 3:16

2-Mar-09 3:16

Hi Harold,

harold aptroot wrote:
sleeping a thousand times per second

you are an optimist then. You may be interested in my article on timers.

Smile | :)

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modified on Sunday, June 12, 2011 8:59 AM

harold aptroot2-Mar-09 4:40

harold aptroot

2-Mar-09 4:40

Lol yea I exaggerated - how about: Up to a thousand times per second but it will never be that much due to the bad timer resolution.
But the idea is the same.. sleeping "many" times per second isn't a good idea.

invader822-Mar-09 4:35

2-Mar-09 4:35

Hmm I think I'll have to be carefull with the m.Set() Smile | :)

but worth trying...

N a v a n e e t h2-Mar-09 1:16

2-Mar-09 1:16

Use the asynchronous fashioned methods. Like BeginXXX() and EndXXX(). There is a Socket.BeginAccept[^] available.

Smile | :)

Navaneeth

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invader822-Mar-09 4:46

2-Mar-09 4:46

I don't understand how that would spare the cpu
or would help me to get rid of Sleep(x);?

I just want my loop to block, so it won't accept any new connections
until the older ones are gone... without using any cpu time.

N a v a n e e t h2-Mar-09 15:32

2-Mar-09 15:32

See MSDN[^] got a sample.

Navaneeth

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Luc Pattyn2-Mar-09 3:20

2-Mar-09 3:20

Hi,

invader82 wrote:
Has anyone a better idea how to keep the cpu down?

Use an event-driven scheme if one is available: getting a signal something must be done, is more efficient than having a loop polling whether somethind should be done all the time. (BTW: Thread.Sleep(1) will take 10 or more msec on average, see my timers article).

If you can't use an event-driven scheme (because no event is available, or you don't trust it sufficiently), implement a polling loop, however give it a delay that fits with your needs, e.g. if the client is a human typing/clicking in a browser, 50 msec would be good enough.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

modified on Sunday, June 12, 2011 8:59 AM

invader822-Mar-09 4:59

2-Mar-09 4:59

I rather wanted something that would really block that loop until
the number of connections drops back below a certain value.
I'll try the ManualResetEvent that harold proposes...
I think it's a "cleaner" solution for the problem
than sleep()

Luc Pattyn2-Mar-09 5:03

Re: land phone call from pc

2-Mar-09 5:03

Yes, ManualResetEvent supports one of several event-driven schemes .NET provides.

Luc Pattyn [Forum Guidelines] [My Articles]

modified on Sunday, June 12, 2011 9:00 AM

land phone call from pc

rizvi_codeproject2-Mar-09 0:29

rizvi_codeproject

2-Mar-09 0:29

Hi,
I'll have to prepare a software in C# that using the software we can call from pc and receive call by pc. obviously a modem is connected with the pc.
I want some idea about this project. if possible then send me some sample code or url for reference..
Please help me... Sigh | :sigh:

Thanks
Rizvi.

Kristian Sixhøj2-Mar-09 4:52

Kristian Sixhøj

2-Mar-09 4:52

rizvi_codeproject wrote:
url for reference..

Oh, you should have said that right away.

Here: http://www.google.com/[^]

Kristian Sixhoej
"You can always become better." - Tiger Woods

[ My blog ]

process details

shefa' isied2-Mar-09 0:22

shefa' isied

2-Mar-09 0:22

hi,i'm trying to get the details of each process in c# but some of its attributes didnt return anything, (i made object of class Process --> p):

1) p.ExitTime;
the ERROR: process was not started by this object

2) p.startInfo.WorkingDirectory;
but it didnt return the directory of the process,just a empty string

3) p.username;
empty string, i searched the net and tried many codes but nothing helped me ,they all return the usename of the computer, i want something like task manager's username:system, local service ....

And one more thing :how does taskmanager calculate cpu usage?

Re: process details

Luc Pattyn2-Mar-09 3:25