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try the following...
<code>
public string ExecuteScalar(string strConnectionSring, string strScript)
{
SqlConnection ObjSqlConnection = null;
SqlCommand ObjSqlCommand = null;
ObjSqlConnection = new SqlConnection(strConnectionSring);
string strMessage = null;
try
{
ObjSqlCommand = new SqlCommand(strScript, ObjSqlConnection);
ObjSqlConnection.Open();
ObjSqlCommand.ExecuteScalar();
strMessage = "Succes";
}
catch (Exception ex)
{
strMessage = ex.Message.ToString();
}
finally
{
ObjSqlConnection.Close();
ObjSqlCommand = null;
ObjSqlConnection = null;
strScript = null;
}
return strMessage;
}</code>
I will not say I have failed 1000 times; I will say that I have discovered 1000 ways that can cause failure – Thomas Edison.
Don't forget to click [Vote] / [Good Answer] on the post(s) that helped you.
Thanks
Md. Marufuzzaman
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Thanks for your help. You saved my life  . I have tried it and it has worked fine. Moreover could you explain how I can fetch the query result ?
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You are most welcome...
Well.... You just need to use dataset to fetch query results.... 
I will not say I have failed 1000 times; I will say that I have discovered 1000 ways that can cause failure – Thomas Edison.
Don't forget to click [Vote] / [Good Answer] on the post(s) that helped you.
Thanks
Md. Marufuzzaman
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I have no idea about dataset  could yo explain it ?
however I tried SqlCeDataReader SqlRd= ObjSqlCeCommand.ExecuteReader(); instead of ObjSqlCeCommand.ExecuteScalar();
and to check if result row number > 0 I used "if (SqlRd.Read() == true)" conditional check. Unfortunately It does not works for query string "SELECT Username, Name, Surname FROM SystemUsers where Username =' " + input + "' and Password = '" +passwd +"'"; there must be one row as a result but It does not return any thing. do you have any idea ?
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use this :
SqlCeDataReader reader;
using (reader = ObjSqlCeCommand.ExecuteReader())
{
while(reader.Read())
{
}
}
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thank you very much
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SqlCommand..::.ExecuteScalar Method:
Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.
SqlCommand.ExecuteReader Method:
Sends the CommandText to the Connection and builds a SqlDataReader.
Dataset:
http://msdn.microsoft.com/en-us/library/system.data.dataset.aspx
I will not say I have failed 1000 times; I will say that I have discovered 1000 ways that can cause failure – Thomas Edison.
Don't forget to click [Vote] / [Good Answer] on the post(s) that helped you.
Thanks
Md. Marufuzzaman
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I am developing an application in which a connection to a server application on another computer within our network is established. I am using a System.Net.Sockets.Socket to establish the connection to said server app. Upon successfully connecting to the server app, I send a connect message with the login credentials the user provided. In response, the server app should send back a message to indicate a successful or unsuccessful login. My problem is this: when running from within the Visual Studio development, it works flawlessly. When I launch the executable directly, I do not receive the return message from the server app. Any ideas?
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Do you log all exceptions? What are the symptoms other than "it does not work"?
Maybe you gave VS a permanent green light in your firewall, and it is blocking your app outside VS?
Luc Pattyn
Local announcement (Antwerp region): Lange Wapper? Neen!
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Luc:
No firewalls are on between "here" and "there". No exceptions are being thrown. The server application is logging the receipt of the message from the client application.
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Odd. Did you try debug build running inside VS? release build running inside VS? debug build double-clicked in bin\debug folder? release build double-clicked in bin\release folder?
the difference would be optimizations (timing difference or bugs), and error handling (VS settings influence some).
Do you use time-outs? with sufficient value? and failures get logged? or is the client hanging, waiting on a reply?
Luc Pattyn
Local announcement (Antwerp region): Lange Wapper? Neen!
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Luc:
There was one point where I was missing code in a catch statement. That was the exception that was getting thrown. After I added code to handle that exception, I discovered that the problem was stemming from a difference in the amount of data included in the message sent from my Test tier versus my local tier. Due to this size difference, a flaw in my received handler was being tripped. Fixed my code and everything works as expected.
Thanks for your question about exceptions. If forced me to go back and check all of my catch statements.
Tim
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yep. catching and somehow showing all exceptions is a powerful technique.
whenever I see an empty catch statement (and that is quite frequently around here, some people think it is wise to skip or postpone error handling), I make sure the perpetrator will not forget about it any time soon ...
Luc Pattyn
Local announcement (Antwerp region): Lange Wapper? Neen!
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Hi, I'm creating an asp.net Pizza order form using c# for a night school course and I have a RadioButtonList for the Size of the pizza and a checkbox list for the Pizza Toppings. Both controls have autopostback enabled so that as a size is selected and a topping is added the Total Price label will automatically calculate the total price and size is selected and toppings added. I have a simple method that adds the ingredients price to the size price as selctions are made. The problem is that the value of the Total Price changes as selections are made to the size (2,4,6,8,10) but if a topping is selected then the value of the total price doesn't add the size price to the toppings price they are still calculated individually, can someone tell from my code how i can write and use my method to total the size price with the topping price? thanks in advance.
<br />
public partial class _Default : System.Web.UI.Page <br />
{<br />
decimal TotalPrice = 0;<br />
decimal IngredientsPrice = 0;<br />
decimal SizePrice = 0;<br />
<br />
private decimal MethodTotalPrice(decimal MethodIngredientsPrice,<br />
decimal MethodSizePrice)<br />
{<br />
decimal MethodTotalPrice;<br />
MethodTotalPrice = MethodIngredientsPrice + MethodSizePrice;<br />
return MethodTotalPrice;<br />
}<br />
<br />
protected void Page_Load(object sender, EventArgs e)<br />
{<br />
<br />
}<br />
protected void RadioButtonList1_SelectedIndexChanged1(object sender, EventArgs e)<br />
{<br />
lblSize.Text = rblSize.SelectedItem.Text;<br />
<br />
if (rblSize.SelectedValue == "Slice")<br />
{<br />
lblSize.Font.Size = 8;<br />
SizePrice = 2;<br />
}<br />
if (rblSize.SelectedValue == "Small")<br />
{<br />
lblSize.Font.Size = 10;<br />
SizePrice = 4;<br />
}<br />
if (rblSize.SelectedValue == "Medium")<br />
{<br />
lblSize.Font.Size = 12;<br />
SizePrice = SizePrice + 6;<br />
}<br />
if (rblSize.SelectedValue == "Large")<br />
{<br />
lblSize.Font.Size = 14;<br />
SizePrice = 8;<br />
}<br />
if (rblSize.SelectedValue == "Xtra Large")<br />
{<br />
lblSize.Font.Size = 16;<br />
SizePrice = 10;<br />
}<br />
TotalPrice = MethodTotalPrice(IngredientsPrice, SizePrice);<br />
lblPriceTotal.Text = TotalPrice.ToString();<br />
}<br />
protected void cblIngredients_SelectedIndexChanged(object sender, EventArgs e)<br />
{<br />
string Message;<br />
Message = "";<br />
for (int i = 0; i < cblIngredients.Items.Count; i++)<br />
{<br />
if (cblIngredients.Items[i].Selected)<br />
{<br />
Message = Message + cblIngredients.Items[i].Text + "<br>";<br />
IngredientsPrice = IngredientsPrice + 1;<br />
}<br />
}<br />
lblIngredients.Text = Convert.ToString(Message);<br />
TotalPrice = MethodTotalPrice(IngredientsPrice, SizePrice);<br />
lblPriceTotal.Text = TotalPrice.ToString();<br />
}<br />
}<br />
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Marcus Farrugia wrote: SizePrice = SizePrice + 6;
Probably not intended
I mean, if you switch from Xtra large to medium, you're suddenly paying 16, right?
Marcus Farrugia wrote: IngredientsPrice = IngredientsPrice + 1;
AKA IngredientsPrice++, just a style thing though. More important is that you don't reset it. It will just keep going up. That is not good.
Concatting "many" strings using the + operator is poor form, better use a StringBuilder, but that's not causing your problem.
Marcus Farrugia wrote: MethodTotalPrice = MethodIngredientsPrice + MethodSizePrice;
Surprising calculation, but if it's supposed to work that way...
edit:  right ASP.NET. Ok ignore this post. Why do people just keep posting ASP.NET questions here instead of at the ASP.NET forum?
Last modified: 45mins after originally posted --
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harold aptroot wrote: Why do people just keep posting ASP.NET questions here
For the same reason they keep advertising ASP.net jobs as C# jobs. 
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Hi,
When one choice changes, how are you going to keep the result from another choice made earlier? The page reloads, doesn't it? With new variables, initialized at zero?
the easiest and safest way is to calculate total prize in a separate method that collects all required data;
then invoke that method from within all your Changed handlers. So every change recalculates the total price.
Luc Pattyn
Local announcement (Antwerp region): Lange Wapper? Neen!
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Well your code is a bit of a mess. As Luc has pointed out, ASP.NET will reset each of those class variables to zero on postback. There is the option of persisting values between postbacks but a more elegant solution would be to calculate the price whenever you need it.
I would approach this as follows, start with a method to do the actual proce calculation
private decimal CalculatePrice()
{
decimal sizePrice = 0;
switch(rblSize.SelectedValue)
{
case "Slice": sizePrice = 8;break;
case "Small": sizePrice = 10;break;
}
decimal ingredientsPrice = 0;
for (int i = 0; i < cblIngredients.Items.Count; i++)
{
if (cblIngredients.Items[i].Selected)
{
ingredientsPrice ++;
}
}
return sizePrice + ingredientsPrice ;
}
Next have this method called when either action is performed
protected void RadioButtonList1_SelectedIndexChanged1(object sender, EventArgs e)
{
decimal totalPrice = CalculatePrice();
lblPriceTotal.Text = totalPrice.ToString();
)
protected void cblIngredients_SelectedIndexChanged(object sender, EventArgs e)
{
decimal totalPrice = CalculatePrice();
lblPriceTotal.Text = totalPrice.ToString();
}
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Marcus Farrugia wrote: I'm creating an asp.net Pizza order form using c# for a night school course
OK, I'm going to apologies in advance if the following is either to simple or too complicated. If you are going to use C# you should really look into object oriented design (lots of references around), but only when and if you are comfortable with control flow logic (loops and descision statements etc). Getting you head around this will save a lot of work in the long run, but it's daunting as you start out (or it was for me anyway )
You should condisder breaking some of your code down further into classes. A class is a way of gathering properties (e.g. Size) and methods (e.g. Add/Remove Toppings) into one logical place (often representing something in the real world). This is known as encapuslation and prevents any unwanted side-effects from other things happening if you do it correctly. e.g. in your example a mistake is causing the total to be incorrect.
For example:
If you create a class called Topping, you could create several of these. The topping might have a property called Description (e.g. Description = "Ham") and a set of prices for each size (there are several way to do this, e.g. have a property for each size, which is less good or consider using a Dictionary)
Now you could have Pizza class, this could have a List of Toppings, a Size (and a list of pizza-base prices for each size, just like the topping) an a calculate cost method. To calculate the cost, you take the pizza-base cost for the current size, and for each topping add it's cost according to the pizza size.
A good initial way to work out which classes, properties and methods you need is to write down what you want to achieve, nouns indicate classes or properties, verbs indicate a method is required.
e.g.
A pizza can come in different sizes and have several toppings added or removed as required. Calculate the cost of the pizza and show to the customer.
Note that you'll see the classes Pizza and Topping I sugested highlighted as well as the size property. Also highlighted are "Add[Topping]" and "Remove[Topping]", I haven't put these on the pizza class directly, though you could. I have suggested you create a property called Toppings which is a List of toppings (List<Topping> google up List<T> for more advice). The list itself has an Add & Remove methods, so you don't have to add them.
This seems like a chore, but 99% of the time it works easier. For example you could now add new types of topping easily or add stuff to save to a database. If you implement it well , new pizza sizes should be easy and the code you write should be more readable, robust & easy to adapt to new requirements (all of which are important when programming)!
Good luck with your course, and I hope you enjoy it. I'm jelous, I wish I could unlearn the stuff I have done, just so I could re-learn it! On the up side I suppose there are lots of cool new things being done in IT to find out about all the time.  I am such a geek!
CCC solved so far: 2 (including a Hard One!)
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Hi! Maxwell. I'm working with ASP C# and i'm trying to up pictures to the file. I have sample code:
string concatName = null, picname = null, strImageFolderPath = null, strImagePath = null;
DateTime now;
HttpPostedFile uploadedImage;
now = DateTime.Now;
concatName = Request.QueryString["||"].ToString() + now.Year.ToString() +
now.Month + now.Day + now.Hour + now.Minute + now.Second;
uploadedImage = FileUpload11.PostedFile;
picname = System.IO.Path.GetFileName("MAI" + concatName + ".jpg");
strImageFolderPath = Path.Combine
(Request.PhysicalApplicationPath, "pictures");
strImagePath = Path.Combine(strImageFolderPath, picname);
uploadedImage.SaveAs(strImagePath); //error "Object reference not set to an instance of an object."
Help me please
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Mix Wheels wrote: uploadedImage.SaveAs(strImagePath); //error "Object reference not set to an instance of an object."
how many references are there in this line? I see 1.
hence uploadedImage is null. fix that.
Luc Pattyn
Local announcement (Antwerp region): Lange Wapper? Neen!
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Hello all,
How can I allow a user to type a letter on the keyboard and have a DataGridView (DGV) change current row to the first occurrence of the letter within a non-Primary Key column.
For example, LastName is a column in a DGV. Typing ‘S’ should change the current row of the DGV to the first Lastname that starts with an ‘S’. Note: LastName is not the primary key of the bound table.
I am using a DataGridView bound to a DataSet.Table[] without a binding source.
Here is a code snippet I tried, but it returns -1:
ds.Tables["Students"].DefaultView.Sort = "LastName";
int intRow = ds.Tables["Students"].DefaultView.Find("S%");
I have also tried this, but it returns zero rows:
ds.Tables["Students"].DefaultView.Sort = "LastName";
DataRowView[] drv = ds.Tables["Students"].DefaultView.FindRows("LastName LIKE 'S'");
Thanks in advance,
KCI
Live long and prosper.
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Isn't the last one missing a wildcard?
JimSchor wrote: ds.Tables["Students"].DefaultView.Sort = "LastName";
DataRowView[] drv = ds.Tables["Students"].DefaultView.FindRows("LastName LIKE 'S*'");
I are Troll
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Hello Troll,
Thanks for the advice.
I just tried it and no difference.
Any more thought anyone?
KCI
Live long and prosper.
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Here is how I eventuall worked this out. I have not tested it deeply so take this only as an outline:
using System.Collections.Generic;
private string strKeyPreview = String.Empty
private List<string> strStudent_List = null;
private void dgv_KeyPress(object sender, KeyPressEventArgs e)
{
strKeyPreview = e.KeyChar.ToString();
int intRow = strStudent_List.FindIndex(StartsWithLetter);
if (intRow >= 0)
{
dgv[3, intRow].Selected = true;
dgv.FirstDisplayedScrollingRowIndex = intRow;
}
}
private bool StartsWithLetter(String s)
{
if (s.StartsWith(strKeyPreview.ToUpper()) == true)
{
return true;
}
else
{
return false;
}
}
strStudent_List = new List<string>();
foreach (DataRow dr in dt.Rows)
{
strStudent_List.Add(dr[2].ToString());
}
Feel free to post improvement ... I'm sure this is not bullet proof as it is untested.
Live long and prosper.
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