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Hi,
ExecuteNonReader: used actions like insert, update, delete
ExecuteScalar: will return an object
for details you can learn from some books about these two.
Thanks,
CommDev
modified 6-Dec-16 1:27am.
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Hi,
ExecuteReader
Do not use: when database query is going to provide for sure exactly 1 record. It may be getting record by its id (which is PK in the database) - GetOrderById and such. In this case use ExecuteNonQuery with output parameters.
Use: when database query is going to provide a set of records. It may be search or report.
ExecuteNonQuery
Use: when we are talking about a single database record - in Update, Insert, Delete and Get by Id. In all these cases we can use input/output/input-output parameters. Please note that from the application architecture point of view it is also good practices when your Insert and Update stored procedure returns changed record exactly like Get By Id method does.
ExecuteScalar
Do not use: when database query returns a single value and this value can be defined as parameter in T-SQL. ExecuteNonQuery with output parameter(s) is always preferred in this case since it is more flexible, tomorrow there will be 2 values therefore having ExecuteNonQuery we do not need to change method signatures.
Use: when database query returns a single value and this value cannot be defined as output parameter, because of T-SQL type limitation for variables. For example type image cannot be output parameter in MSSQL.
The most common example for ExecuteScalar is fetching a single image stored in the database and converting it to array of bytes. If you google it - most examples will demonstrate using of ExecuteReader to accomplish image handler, however ExecuteScalar will be more scalable and faster.
Conclusion
Always use ExecuteNonQuery except: when you have a set of records - use ExecuteReader and when you have a single output value that cannot be defined as a parameter - use ExecuteScalar. Hope this helped to clarify something. Enjoy 
Comm100 - Leading Live Chat Software Provider
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Thanks CommDev.
But if I am going to return GetOrderById.. what's the difference if I am going to use ExecuteNonQuery with Output parameter or ExecuteReader with return SqldataReader?
Does it make a difference specially performance wise?
Technology News @ www.JassimRahma.com
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hi,
Generally we use execute scalar function for displaying the first column and first row, but if we use ExecuteNonReader it will show error why because in asp.net only 3 commands are there ExecuteReader()
ExecuteNonQuery()
ExecuteScalar() this is the option to get one value from the database.
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Guys;
I am developing a control that should contain html elements
like
<web:CommandLink ID="cmdDelete" runat="Server" >
<img alt="Delete" src="images/delete.jpg" />
</web:CommandLink>
I started with implementing IParserAccessor.
Am I in the right direction ?
Thank you.
Help people,so poeple can help you.
modified 24-Dec-12 5:29am.
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So your trying to make a server or user control?
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A server one.
the new thing is I implemented IParserAccessor.AddParsedSubObject this way
Public Sub AddParsedSubObject(ByVal obj As Object) Implements System.Web.UI.IParserAccessor.AddParsedSubObject
If (TypeOf (obj) Is LiteralControl) Then
Me._templateText = CType(obj, LiteralControl).Text
Else
Throw New Exception("Not supported")
End If
End Sub
it works fine but it gives me the validation error 'img cannot be nested with commandlink'.
what should I do to avoid that?
Help people,so poeple can help you.
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Hi All
i have a gridview
<asp:GridView ID="GridView2" runat="server" Width="100%"
AutoGenerateColumns="False">
<Columns>
<asp:BoundField DataField="description" HeaderText="Description" >
<ItemStyle HorizontalAlign="Center" VerticalAlign="Middle" />
</asp:BoundField>
<asp:BoundField DataField="Amount" HeaderText="Amount" >
<ItemStyle HorizontalAlign="Center" VerticalAlign="Middle" />
</asp:BoundField>
<asp:TemplateField HeaderText="Month">
<ItemTemplate>
<asp:CheckBox ID="CheckBoxJan" runat="server" Text="Jan" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxFeb" runat="server" Text="Feb" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxMar" runat="server" Text="Mar" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxApr" runat="server" Text="Apr" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxMay" runat="server" Text="May" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxJun" runat="server" Text="Jun" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxJul" runat="server" Text="Jul" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxAug" runat="server" Text="Aug" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxSep" runat="server" Text="Sep" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxOct" runat="server" Text="Oct" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxNov" runat="server" Text="Nov" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
<asp:CheckBox ID="CheckBoxDec" runat="server" Text="Dec" AutoPostBack="True"
oncheckedchanged="CheckBoxJan_CheckedChanged" />
</ItemTemplate>
<ItemStyle HorizontalAlign="Center" VerticalAlign="Middle" />
</asp:TemplateField>
</Columns>
</asp:GridView>
and i am using checked change event for checkbox as
protected void CheckBoxJan_CheckedChanged(object sender, EventArgs e)
{
string desc = "";
Double amount = 0;
for (Int32 i = 0; i < GridView2.Rows.Count; i++)
{
double amt = 0;
CheckBox checkBox1 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxJan");
bool isChecked1 = checkBox1.Checked;
CheckBox checkBox2 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxFeb");
bool isChecked2 = checkBox2.Checked;
CheckBox checkBox3 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxMar");
bool isChecked3 = checkBox3.Checked;
CheckBox checkBox4 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxApr");
bool isChecked4 = checkBox4.Checked;
CheckBox checkBox5 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxMay");
bool isChecked5 = checkBox5.Checked;
CheckBox checkBox6 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxJun");
bool isChecked6 = checkBox6.Checked;
CheckBox checkBox7 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxJul");
bool isChecked7 = checkBox7.Checked;
CheckBox checkBox8 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxAug");
CheckBox checkBox9 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxSep");
bool isChecked8 = checkBox8.Checked;
CheckBox checkBox10 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxOct");
bool isChecked9 = checkBox9.Checked;
CheckBox checkBox11 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxNov");
CheckBox checkBox12 = (CheckBox)GridView2.Rows[i].Cells[2].FindControl("CheckBoxDec");
bool isChecked10 = checkBox10.Checked;
bool isChecked11 = checkBox11.Checked;
bool isChecked12 = checkBox12.Checked;
if (isChecked1 && checkBox1.Enabled==true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Jan" + ",";
}
if (isChecked2 && checkBox2.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Feb" + ",";
}
if (isChecked3 && checkBox3.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Mar" + ",";
}
if (isChecked4 && checkBox4.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Apr" + ",";
}
if (isChecked5 && checkBox5.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "May" + ",";
}
if (isChecked6 && checkBox6.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Jun" + ",";
}
if (isChecked7 && checkBox7.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Jul" + ",";
}
if (isChecked8 && checkBox8.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Aug" + ",";
}
if (isChecked9 && checkBox9.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Sep" + ",";
}
if (isChecked10 && checkBox10.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Oct" + ",";
}
if (isChecked11 && checkBox11.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Nov" + ",";
}
if (isChecked12 && checkBox12.Enabled == true)
{
amt = Convert.ToDouble(GridView2.Rows[i].Cells[1].Text);
amount = amount + amt;
desc = desc + "Dec" + ",";
}
}
Label24.Text = amount.ToString();
Label17.Text = (Convert.ToDouble(Label23.Text) + Convert.ToDouble(Label24.Text) + Convert.ToDouble(Label27.Text)).ToString();
Label29.Text = desc;
}
so here after every checked change page is getting reloaded but i want to do this in javascript(client side)
so please help me to do this
regards
Ravi kant
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helo frnds,
im trying to capture updated data from gridview upon check box selection..
however im unable to retreive new data..
it alwasy capture old data...pls help me...
i haave used gridediteventargs..but in vain......
i want to capture new data in button click event
best rgrds
nancy
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Ma'am;
You have a gridview with a check box in each row and you want an array of the selected rows keys. right?
if so, you should have a template column that contain a check box with a specific name say 'Selection'
<input type="checkbox" name="Selection" value="<%# Eval("Key")%>" />
when you postback the page you can get the array using Request["Selection"]
Help people,so poeple can help you.
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Member 9707207 wrote: im trying to capture updated data from gridview upon check box selection..however im unable to retreive new data..
Just check if you are binding the grid data again on postback. If so, before the update event is raised the data will be back to previous state and changes will be lost.
You need to put the databind code for the grid in Page.IsPostback property to avoid a rebind until unless specified in a postback.
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How to convert English words to Hindi words with help of coding it is possible with out any data base?
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Think about this: how many words do you expect to convert? Can you keep that many words somewhere without a database of some sort?
One of these days I'm going to think of a really clever signature.
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Hi,
You can try Google Translator API. Given link may be useful to you.
Google Translator[^]
Maulik Dusara
Sr. Sofware Engineer
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Tarani Dutt Joshi wrote: with help of coding it is possible with out any data base
If you plan to translate by your own, you would need database! If you want the conversion without too much of an effort, you can try a 3rd party translation service where you pass on the English words and get back the translated value. Google translate could be of help to start with.
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I have a link of one webpage which is developed in dotnetnuke CMS and i want to view page source of page, the problem is that dotnetnuke does nt allow me to view page source programmatically.
How can I view page source programmatically?
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Hi,
Why I am getting this error when insert is successful?!!! it should redirect to ~/Channels!
here is my code:
try
{
sql_connection = new MySqlConnection(ConfigurationManager.ConnectionStrings["SQLdb"].ConnectionString);
sql_connection.Open();
if (RouteData.Values["GUID"].ToString() == "New") sql_command = new MySqlCommand("sp_add_new_channel", sql_connection);
else sql_command = new MySqlCommand("sp_update_channel", sql_connection);
sql_command.CommandType = CommandType.StoredProcedure;
if (RouteData.Values["GUID"].ToString() == "New") sql_command.Parameters.AddWithValue("param_member_id", Convert.ToInt32(Session["member_id"])).MySqlDbType = MySqlDbType.Int32;
else sql_command.Parameters.AddWithValue("param_channel_guid", RouteData.Values["GUID"].ToString()).MySqlDbType = MySqlDbType.VarChar;
sql_command.Parameters.AddWithValue("param_channel_name", txtChannelName.Text.Trim()).MySqlDbType = MySqlDbType.VarChar;
sql_command.Parameters.AddWithValue("param_channel_address", txtChannelAddress.Text.Trim()).MySqlDbType = MySqlDbType.VarChar;
sql_command.Parameters.AddWithValue("param_channel_language", Convert.ToInt32(cboLanguage.Value)).MySqlDbType = MySqlDbType.Int32;
sql_command.Parameters.AddWithValue("param_channel_description", txtChannelDescription.Text.Trim()).MySqlDbType = MySqlDbType.VarChar;
sql_command.Parameters.AddWithValue("param_channel_allow_comment", chkAllowComment.Checked).MySqlDbType = MySqlDbType.Bit;
sql_command.Parameters.AddWithValue("param_channel_allow_like", chkAllowLikeIt.Checked).MySqlDbType = MySqlDbType.Bit;
sql_command.Parameters.AddWithValue("param_channel_allow_share", chkAllowShare.Checked).MySqlDbType = MySqlDbType.Bit;
sql_command.Parameters.AddWithValue("param_show_profile_photo", chkShowProfilePhoto.Checked).MySqlDbType = MySqlDbType.Bit;
if (RouteData.Values["GUID"].ToString() == "New") sql_command.Parameters.Add("param_channel_guid", MySqlDbType.VarChar).Direction = ParameterDirection.Output;
sql_command.Parameters.Add("param_is_exist", MySqlDbType.Bit).Direction = ParameterDirection.Output;
int result_rows = sql_command.ExecuteNonQuery();
if (Convert.ToBoolean(sql_command.Parameters["param_is_exist"].Value) != true)
{
website_event_log.add_event_log("Membership", txtChannelName.Text.Trim(), "You have successfully signed up");
Response.Redirect("~/Channels", true);
}
else
{
Session["message_title"] = "Error";
Session["message_title_Color"] = Color.Red.ToArgb();
Session["message_text"] = "The same channel address already exists. Please try another address.";
Session["message_button_title"] = "Back";
Session["message_button_url"] = Request.UrlReferrer.ToString();
Response.Redirect("~/Message", false);
}
}
catch (Exception exp)
{
Session["message_title"] = "ERROR..";
Session["message_text"] = String.Format("Please try again.......{0}{1}", "", exp.Message);
Session["message_button_title"] = "Back to Sign-in";
Session["message_button_url"] = Request.UrlReferrer.ToString();
Response.Redirect("~/Message", false);
}
finally
{
if (sql_connection != null)
{
if (sql_connection.State == ConnectionState.Open)
sql_connection.Close();
}
}
Technology News @ www.JassimRahma.com
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Either the cast to "param_is_exist" failed, or website event log failed. I really think you need to move that whole code block to finally.
finally
if (Convert.ToBoolean(sql_command.Parameters["param_is_exist"].Value) != true)
{
website_event_log.add_event_log("Membership", txtChannelName.Text.Trim(), "You have successfully signed up");
Response.Redirect("~/Channels", true);
end try
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but the finally will run no matter what try was successful or error was catched? right?
Technology News @ www.JassimRahma.com
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Yes that is correct.
So you make an exitCode as an integer = 2
exitCode integer = 2
do your checks,
in the catch, make exitCode = 1
in the Try, exitCode = 0
So in the finally, if the exitCode is 2, it's complete failure
if the exitCode is 1, you trapped the error, log it or display it
if the exitCode is 0, the program ran correctly
exitCode integer = 2;
Try
exitCode = 0
catch ex as exception
exitCode = 1
Finally
switch exitCode {
case 2
case 1
case 0
response.redirect("~/correct");
}
}
}
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so where is the problem?
here is the code after commenting the try..catch..finally:
sql_connection = new MySqlConnection(ConfigurationManager.ConnectionStrings["SQLdb"].ConnectionString);
sql_connection.Open();
if (RouteData.Values["GUID"].ToString() == "New") sql_command = new MySqlCommand("sp_add_new_channel", sql_connection);
else sql_command = new MySqlCommand("sp_update_channel", sql_connection);
sql_command.CommandType = CommandType.StoredProcedure;
if (RouteData.Values["GUID"].ToString() == "New") sql_command.Parameters.AddWithValue("param_member_id", Convert.ToInt32(Session["member_id"])).MySqlDbType = MySqlDbType.Int32;
else sql_command.Parameters.AddWithValue("param_channel_guid", RouteData.Values["GUID"].ToString()).MySqlDbType = MySqlDbType.VarChar;
sql_command.Parameters.AddWithValue("param_channel_name", txtChannelName.Text.Trim()).MySqlDbType = MySqlDbType.VarChar;
sql_command.Parameters.AddWithValue("param_channel_address", txtChannelAddress.Text.Trim()).MySqlDbType = MySqlDbType.VarChar;
sql_command.Parameters.AddWithValue("param_channel_language", Convert.ToInt32(cboLanguage.Value)).MySqlDbType = MySqlDbType.Int32;
sql_command.Parameters.AddWithValue("param_channel_description", txtChannelDescription.Text.Trim()).MySqlDbType = MySqlDbType.VarChar;
sql_command.Parameters.AddWithValue("param_channel_allow_comment", chkAllowComment.Checked).MySqlDbType = MySqlDbType.Bit;
sql_command.Parameters.AddWithValue("param_channel_allow_like", chkAllowLikeIt.Checked).MySqlDbType = MySqlDbType.Bit;
sql_command.Parameters.AddWithValue("param_channel_allow_share", chkAllowShare.Checked).MySqlDbType = MySqlDbType.Bit;
sql_command.Parameters.AddWithValue("param_show_profile_photo", chkShowProfilePhoto.Checked).MySqlDbType = MySqlDbType.Bit;
if (RouteData.Values["GUID"].ToString() == "New") sql_command.Parameters.Add("param_channel_guid", MySqlDbType.VarChar).Direction = ParameterDirection.Output;
sql_command.Parameters.Add("param_is_exist", MySqlDbType.Bit).Direction = ParameterDirection.Output;
int result_rows = sql_command.ExecuteNonQuery();
if (Convert.ToBoolean(sql_command.Parameters["param_is_exist"].Value) != true)
{
website_event_log.add_event_log("Membership", txtChannelName.Text.Trim(), "You have successfully signed up");
Response.Redirect("~/Channels", true);
}
else
{
Session["message_title"] = "Error";
Session["message_title_Color"] = Color.Red.ToArgb();
Session["message_text"] = "The same channel address already exists. Please try another address.";
Session["message_button_title"] = "Back";
Session["message_button_url"] = Request.UrlReferrer.ToString();
Response.Redirect("~/Message", false);
}
Technology News @ www.JassimRahma.com
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You have to close the connection first before issuing a response.redirect, well you should at least, or else it can cause an error, or leave too many copies of the connector open. I would have to do research on that to confirm it, but I don't redirect when reading or writing data to a database.
Response.Redirect is the last thing you want to do in a sub, after closing and disposing of objects.
It's actually better to write a function without response.redirect, and have the function return a result or exit code, and then redirect.
if (0 = createStoredProcedure()) then
response.redirect("~/option")
else
response.redirect("~/error")
End if
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Is it possible to get a Tooltip or some pop up when i mouse over on an image button in asp?
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