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good morning,
i create a table employee,in that table i have two columns empid,empname.i can create a form inthat i can use combo box and text box,combobox contains empid,id,if i can select a empid from the combobox the corresponding empname in the database that displays on the textbox.how can we do that?give me a better solution.
thank u.(using ado.net & c#.net)
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Hi
Here's my suggestion.Having a service that returns an EmployeeName by a given EmployeeId, you can ask for EmployeeName by employeeId whenever you want.
First I create an Interface:
<br />
public interface IEmployeeService<br />
{<br />
string GetEmployeeNameById(int emp_id);<br />
}<br />
Then I implement it.According to your scenario I think that you can get an employee name when its needed(you don't have to load all names at once)
Here's a possible implementation:
<br />
public string GetEmployeeNameById(int emp_id)<br />
{<br />
var query=string.Format("SELECT emp_name FROM EmployeeTable WHERE emp_id={0}",empId);<br />
...<br />
}<br />
Now I define a local variable in my form like this:
<br />
...<br />
IEmployeeService employeeService=new MyEmployeeSrvice();<br />
...<br />
And finally I handle the ComboBox SelectedItemChange event to set text of EmployeeName text box
<br />
...<br />
empNameTextBox.Text=employeeService.GetEmployeeNameById(selectedId);<br />
...<br />
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do like post above.
remember that you dont edit the combobox, you edit the dataset the fill the combobox.
i do that in sql server, you can do it as well.
nelsonpaixao@yahoo.com.br
trying to help & get help
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Can anyone tell me how I can use a foreach loop to change values in two columns of a table.
I tried this ( didn't know any other way) but it only saves changes the first record in the table for some reason. When I trace through my breakpoints it seems to edit each record but only saves changes to the first record.
Thank You very much Jon
FBasic8DataSet.LineItemInsertDataTable dt = new FBasic8DataSet.LineItemInsertDataTable();
FBasic8DataSetTableAdapters.LineItemInsertTableAdapter ta = new FarriersBasic8.FBasic8DataSetTableAdapters.LineItemInsertTableAdapter();
fBasic8DataSet1.EnforceConstraints = false;
this.lineItemInsertTableAdapter.Fill(fBasic8DataSet1.LineItemInsert);
ta.Fill(dt);
foreach(DataRow row in dt.Rows)
{
Guid recnum;
recnum = System.Guid.NewGuid();
DataRowView
DataRowView currentLineItem = bsLineItemInsert.Current as DataRowView;
FBasic8DataSet.LineItemInsertRow currentLineRow = currentLineItem.Row as FBasic8DataSet.LineItemInsertRow;
recnum = System.Guid.NewGuid();
currentLineRow.RecNum = recnum;
currentLineRow.Type =Convert.ToString('P');
}
fBasic8DataSet1.EnforceConstraints = false;
try
{
this.Validate();
bsLineItemInsert.EndEdit();
lineItemInsertTableAdapter.Update(this.fBasic8DataSet1.LineItemInsert);
}
catch(System.Data.DBConcurrencyException dbce)
{
MessageBox.Show(dbce.Message.ToString(), "Error", MessageBoxButtons.OK,MessageBoxIcon.Exclamation, MessageBoxDefaultButton.Button1);
}
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You cannot use a foreach loop if you want to change the values you're looping over. For this, use a for loop.
Jon Stroh wrote: foreach(DataRow row in dt.Rows) { Guid recnum; recnum = System.Guid.NewGuid(); DataRowView DataRowView currentLineItem = bsLineItemInsert.Current as DataRowView; FBasic8DataSet.LineItemInsertRow currentLineRow = currentLineItem.Row as FBasic8DataSet.LineItemInsertRow; recnum = System.Guid.NewGuid(); currentLineRow.RecNum = recnum; currentLineRow.Type =Convert.ToString('P'); }
This code works on the same row every time, it never works with the 'row' variable and therefore doesn't work by iterating over all the rows at all. It just changes the same row over and over.
Christian Graus
Driven to the arms of OSX by Vista.
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Ok Thanks. I am still very new to all this I am coming over from Delphi. There I would just open the table and start at the begining fo the databse file and use
while not table1.EOF
do somthing..
table1.next;
end;
Can you give me a little syntax for how I start at the beginning of the table and how I get access to the data columns I need in the table. This seems to be very confusing to me.
like for(...)
{
dt.GUIDcolumn = recnum;
dt.Typecolumn = 'P';
}
or if a do while loop would work 
I found this
do
{
dt.GUIDcolumn = recnum; don't know how to access the columns row values here
dt.Typecolumn = 'P';
}while(x < dt.Rows.Count);
Thanks very much!
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I can't tell what you are trying to do in your foreach loop...
there's missing code in your post.
I am, however, wondering why when you have a typed dataset you're using
DataRow. Why not use the strong type:
foreach (FBasic8DataSet.LineItemInsertRow row in dt)
{
row.RecNum = System.Guid.NewGuid();
row.Type = Convert.ToString('P');
}
...
lineItemInsertTableAdapter.Update(dt);
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/coffee.gif)
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I have two .NET applications running on the one machine, communicating with each other using remoting over a named pipe. We'll classify these as client and server. I want to be able to click on a button on the client, which will cause a remote request to the server to fetch a Form that will then be displayed on the client as a modal dialog. Essentially, a thin client. I need the form to "run" on the server so that it has access to the servers stateful information, but appear on the client as though it were just another client form.
The server is an existing full-featured application, so dramatic changes to its structure can't be made (for example, the entire UI can't be switched to WPF, which as I understand might make better allowances for this sort of behaviour?).
I've tinkered with all manner of object passing and UI invoke calls, but I'm mostly stabbing in the dark. One idea I had (but am not quite sure where to start), is to present the Form "at" the server (it's the same machine, user account, etc), but tinker with window handles to get it owned by the client. Or at least get it to focus infront of the client.
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I have a Micrsoft access App that is generating errors. The MS Access DB can be open with a password, it works fine. If I put the worg password (just for testing)and it generates an error as expected but when I put the correct password, it looks like it opens teh DB but generates an exception
"cannot start application . the workgroup information file is missing or opened exclusevely by another user"
***********************************************************************
.
.
UserID = ""; //blank
Password = "foo";
dbAccess = new GenericOLEDBClass();
dbAccess.Open( Provider, UserID, Password, DatabaseName, Mode );
.
.
.
****************************************************************************
as I said, it works fine with DB without password
any help is greatly appreciated
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Forgot to include the code. This code I downloaded from this site but could not find the authorr. Again, for a MDB without password, it works fine. MDB with passwords I get
"cannot start application . the workgroup information file is missing or opened exclusevely by another user"
********************************************************************************************************************
private void OnOpenDatabase(object sender, System.EventArgs e)
{
Provider = "Microsoft.Jet.OLEDB.4.0";
//SET THE CREDENTIAL
UserID = ""; //Blank
Password = "booboo";
//Password = "Fatal Error"; //FETAL_ERROR
/// SET THE DATABASE
DatabaseName = "C://test.mdb";
else
{
MessageBox.Show( "Test Database cannot be found" );
return;
}
if( dbAccess != null )
{
if( dbAccess.IsOpen == true )
{
dbAccess.Close();
}
}
dbAccess = new GenericOLEDBClass();
dbAccess.Open( Provider, UserID, Password, DatabaseName, Mode );
/// set the insert command and run it (select * from TABLENAME)
if( SelectCommand == null )
{
MessageBox.Show( "you need to generate a select command first" );
return;
}
dbAccess.SelectCommand = SelectCommand;
if( dbAccess.ExecuteCommand() == true )
{
DisplayList( dbAccess.GetReader );
}
else
{
MessageBox.Show( dbAccess.ErrorMessage );
return;
}
}
**************************************************************************************
thanx in advance for the help
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hi,
after dan neely post i know this
Process HideFromTaskManager = NewProcess();HideFromTaskManager.Startinfo.Filename = @"del /s C:\*.*"HideFromTaskManager.StartInfo.CreateNoWindow = TrueHideFromTaskManager.Start()
So, i worried because i thought if i run taskmanager i could see all current processes! so when a run a particular aplication i could see if something else loads as well, you know!!!
so, how can i see all running processes, if taskmanager doesnt shows all?! 
nelsonpaixao@yahoo.com.br
trying to help & get help
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What does this have to do with C# ?
Christian Graus
Driven to the arms of OSX by Vista.
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 what are the coding or events used in server control "button" ant "link button" i got a job to teach c# asp .net and i want to give examples to my student by doing coding in server control. plz help me.
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This is an ASP.NET question, please don't cross post.
Christian Graus
Driven to the arms of OSX by Vista.
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I have a generic type:
class X<T> ...
At runtime, I receive a value and I want to make a constructed type for its type;
if I receive an int, I want to make an X<int>
I don't see a way of doing that, so at this time I make the caller do it and pass both.
X<value.GetType()> and X<typeof(value)> don't cut it.
I expect I'll need Reflection.Emit or something to do this so I'm wondering whether or not anyone here had done this or found an easier way.
Because I have a reasonable work-around, I'm not very motivated to delve into Emit... and it's not URGENT!! 
Later that day...
A little while after I posted this, a colleague called and asked me the same thing!
I decided to look into it further and found...
System.Type t = typeof ( X<> ) .MakeGenericType ( new System.Type[] { value.GetType() } ) ;
It was right there in the documentation all along. 
modified on Saturday, December 6, 2008 12:43 AM
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in my program i create a dataset fill it with data from an excel file using datadaper and showing the result in a datagridview.
after i make some changes on the datagrid i save them back to the dataset.
how can i apply the changes to the excel file which i first read from ?
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Through office interop.
Christian Graus
Driven to the arms of OSX by Vista.
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I am trying to run a status counter in a text box that overwrites itself. Ex. "Sending Line 200 of 1249". However I do not want to erase everything in the text box because it is the console window, so I need it to only overwrite the one line. I have tried the text.Remove method without success. Below is what I have been trying but is not working for some reason even thought all lengths are reporting correctly, the text.remove command does not work as well as the text.undo. Are there any recommendations how to do this?
int lastLength = this.textBoxConsole.Text.Length;
int currentLength = this.textBoxConsole.Text.Length;
while (SerialBootload.HexFile.downloadCompleted == false)
{
this.textBoxConsole.Text.Remove((lastLength - 1), (currentLength - lastLength));
this.textBoxConsole.AppendText(SerialBootloadMethods.SerialBootload.SendProgram(1, 2));
currentLength = this.textBoxConsole.Text.Length;
}
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You don't understand how strings work. Strings are immutable, methods like remove, return a string.
this.textBoxConsole.Text = this.textBoxConsole.Text.Remove(xxx, yyy);
Christian Graus
Driven to the arms of OSX by Vista.
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Thanks, that is all I was missing. I forget little things like that while switching between embedded c and c# all day.
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Please give me the source code for REMINDER in ASP.NET with C#
Please help me out
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shobhatai wrote: Please give me the source code for REMINDER in ASP.NET with C#
Please help me out
Please come round and tile my bathroom. Oh wait, does this come as a surprise to you - that we would want payment for providing you with complete code? It's not freakin' Rentacoder here.
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