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Use this pattern:
OleDbParameter param = new OleDbParameter();<br />
param.DbType = DbType.Int32;<br />
param.Value = 15;<br />
<br />
command.Parameters.Add(param);
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Those are MySql named parameters.
He uses Access I think.
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private const string ConString ="Provider=MSDAORA;Data Source=ESPCS;User ID=espcs_users;Password=jtechusers;Persist Security Info=True";
private const string GetEmployeeByName= "select empno,name,grade,desgn,section from espcs.emp where status='T' and " +
" empno = @empno";
when i run this code it gives an exception "some error occured during processing of command"
public DataSet GetEmpByName(int name)
{
try
{
using (OleDbConnection con = new OleDbConnection (ConString))
{
con.Open ();
OleDbCommand com = new OleDbCommand (GetEmployeeByName ,con);
OleDbParameter par = new OleDbParameter ();
par.DbType = System .Data.DbType.Int32;
par.Value = name;
com.Parameters.Add(par);
OleDbDataAdapter dr = new OleDbDataAdapter (com);
DataSet ds = new DataSet ();
dr.Fill (ds);
return ds;
hello
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Hi,
I don't why it giving error but I use same code as you use except I use the MSACCESS
as database and it is running successfully
public DataSet GetEmpByName(int empId)
{
string ConString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\\test.mdb";
string GetEmployeeByName = "select * from Emp where Empid = @empno";
DataSet ds = new DataSet();
try
{
OleDbConnection con = new OleDbConnection(ConString);
con.Open();
OleDbCommand com = new OleDbCommand(GetEmployeeByName, con);
OleDbParameter par = new OleDbParameter();
par.DbType = System.Data.DbType.Int32;
par.Value = empId;
com.Parameters.Add(par);
OleDbDataAdapter dr = new OleDbDataAdapter(com);
dr.Fill(ds);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message.ToString());
}
return ds;
}
![Rose | [Rose]](https://codeproject.freetls.fastly.net/script/Forums/Images/rose.gif)
Regards
Pankaj Joshi
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You Can also add the parameter name to like
par.ParameterName = "@empno"; 
Regards
Pankaj Joshi
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Yes, I think that's the problem. When using the @param form you soulb also specify the parameter name. But if you use unnamed parameters: ?, then there's no need for that. You just have to add them in the right order.
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I am designing a PDA application using the .NET CF, but I guess this issue would be the same irrespective of it being .NET Framework or .NET Compact Framework..
I have a button and I want to make it have like a button-down event. For example, a form has a mousedown and when the mouse button is down, there is an eventhandler mousedown for it.
I want my button to do the same. Note that the mousedown event doesn't exist for a button. Even setting a mousedown event on the form which contains the button doesn't do the trick (clicking the button does not fire the mousedown event of the form)..
what I want to do is have a facility in my application like while the button is being pressed (for example it can remain pressed for 5 seconds), keep changing the value of another control..
Any help would be highly appreciated.
Cheers,
David
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What if you use the mouse down event and check for the position of the cursor to be inside your button. Wouldn't that have the same outcome?
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I thought of that too.. But it doesn't help.. because when you click the button, the mousedown event of the form doesn't get fired
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What makes you think the MouseDown event doesn't exist for a Button?
According to the documentation, the MouseUp and MouseDown events are part of the Control class and supported in CF 1.0 and 2.0 as well.
Since Button inherits from Control, these events do exist.
Regards,
mav
--
Black holes are the places where God divided by 0...
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Well.. I can't find them in the property window of the button. I have KeyDown, KeyUp and a bunch of other events but not MouseDown and MouseUp.
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Sir,
I am writing a program that return the current file size in MB
my file size in bytes is 4,412,471 and windows shows it 4.20 MB.
for that I write following code
System.IO.FileInfo objNew = new System.IO.FileInfo("C:\\\\test.rar");
decimal val=objNew.Length / 1048576;
string str = String.Format("{0:F2}", val);
but when i print the str it shows 4.00 what is the problem ...?
I think when (objNew.Length / 1048576) execute it give 4 not 4.2 please give me solution
Regards
Pankaj Joshi
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pankaj.indore wrote: decimal val=objNew.Length / 1048576;
change the above to:
decimal val=objNew.Length / 1048576m;
Try to discover why the avove solves
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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It running now...
What is the logic Behind that...?
Regards
Pankaj Joshi
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The two operands of the division are both integers hence an integer division is performed, giving 0 as result (the latter is then converted to decimal type, but you've already lost your decimal digits ). By appending an m you force the compiler to interpeter the operand as a decimal and hence to perform a division between decimals yelding the correct result.
BTW the same chan be obtained explicitely casting one of the operands to decimal type, e.g.:
decimal val= (decimal)objNew.Length / 1048576;
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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pankaj.indore wrote: decimal val=objNew.Length / 1048576;
AS the number on the right hand side of the operator is an int, it will return an int. Replace 1048576 with 1048576.00
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )
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Thx Sir,
its running now...
But what is the actual problem i can't get yet...?
i don't think their is a difference between 1048576.00 and 1048576
please clear it to me.
Regards
Pankaj Joshi
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1048576 is a literal of the type int.
1048576.0 is a literal of the type double.
When you do a division where both operands are int, the result is an int.
When you do a division where one or both of the operands are double, the result is a double.
1048576m is a literal of type Decimal. I would suggest that you avoid the Decimal data type, unless you actually need it's higher precision. (Which you don't do in this case.)
---
single minded; short sighted; long gone;
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Thx For your Reply,
I got the actual problem but still have a doubt see code below
Dim d as double
d=5/3
messagebox.show(k.tostring())
result 1.666666667
but in C# it give 1 whyyyyyyyyyyyyyyyy
I know your answer is int/int result int . but my dear friend type casting proves maths wrong...?
universe know this 5/3 = 1.666666....
why C# dosen't...?
Regards
Pankaj Joshi
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pankaj.indore wrote: I know your answer is int/int result int . but my dear friend type casting proves maths wrong...?
universe know this 5/3 = 1.666666....
why C# dosen't...?
I don't remember much VB, but I think equivalent to 5/3 in C# is 5 div 3 in VB. Do you know the difference now?
"Throughout human history, we have been dependent on machines to survive. Fate, it seems, is not without a sense of irony. " - Morpheus
"Real men use mspaint for writing code and notepad for designing graphics." - Anna-Jayne Metcalfe
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pankaj.indore wrote: Dim d as double
d=5/3
messagebox.show(k.tostring())
result 1.666666667
but in C# it give 1 whyyyyyyyyyyyyyyyy
Christian already explained it to you.
5 and 3 are both integers. If you do integer division your result will be an integer.
1.667 is not an integer.
pankaj.indore wrote: universe know this 5/3 = 1.666666....
Only when it is doing floating point division. When it is doing integer division the result is 1.
Obviously VB performs floating point division, while C# uses integer division (unless told not to, by having the values cast before).
Upcoming events:
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Never write for other people. Write for yourself, because you have a passion for it. -- Marc Clifton
My website
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This VB code:
d = 5 / 3
is equivalent to this C# code:
d = (double)5 / (double)3;
The / operator in VB always does floating point division, converting the operands if needed.
---
single minded; short sighted; long gone;
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actually i m new to dot net
i m using oledb connection
and my query is
"select * from tableabc where name = ? and id = ?"
i dont know how to map these parameters to my command object can any body tell me please
thanks
hello
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Before posting your questions here in the forum did you read the guidlines of how to post the question in the forum.
pls make your subject with suitable topic relevant to your question.
Don't name your subject as hi, hi all.
pls be specific in your subject and post the questions here.
Regards,
Satips. ![Rose | [Rose]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/rose.gif)
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Create OleDbParameter objects. Assign them a data type and a value and add them to the collection of parameters of the command object IN THE EXACT ORDER THEY APPEAR IN THE STATEMENT.
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