Web Forms :: Declaring The SqlConnection And SqlCommand Objects Without CodeBehind?
Sep 11, 2010
Declaring the SqlConnection and SqlCommand objects in a webform without CodeBehind I am trying to query data from a MS SQL server with a C# web form without "CodeBehind". I want to write the information to a table in the web form's body.
I am having trouble declaring the SqlConnection and SqlCommand objects that connect to the server.
How do you use "using System;", "using System.Data;", "using System.Data.SqlClient" inside the script element of an .ASPX file?
I'm trying to determine whether it is better to declare the connection outside with it's own using statement or to create it inside the sqlcommand itself. This is in regards to a single command interaction with the database (no loops).
I want to declare a Dictionary<string, object> variable but don't know where/how to. The values in the dictionary will be objects from the Page (ListBoxes, DropDownLists, etc) so I can't exactly create a class somewhere else. Is there any way I can make this variable accessible from each method in the codebehind?
How can I bind an object to a dropdown list or gridview ? I am writing an application where my code behind calls an instance and bind the list to either dropdown or gridview.For example:
have some Objects, lets say Employee and Role defined as below and I have defined relationships in my database that gives me a list of objects say employees and thanks to my framework each employee object also has a Role object linked via the RoleIDID, UserName, Password, Email, RoleIDRoleID, RoleNameSo in code I can do something like this
I know how to bind a simple objects to a dropdown list. However I am having problems binding my objects which contains sub objects to the control.i.e. with simple object i just do ddl.DataValueField = "myproperty" with my objects they contains sub objects which i want to bind. I have tried ddl.DataValueField = "sub-object.myproperty" which doesnt work.
I have a Interface for CRUD operations.and some classes implemented it.I want to design a user control that have two buttons:insert and delete,to reuse this control over my forms.this class must have a instance of my interface to do insert and delete tasks (if I'm right).this is my interface:
[Code]...
my problem is,i can't declare a property of type ISchoolSystemRepository in user control,because i must pass T for interface.
What is the use of declaring the static class. I know that we cant create the object for the static class but i want to know that is the use of creating the class as static.
I have been using .NET 2.0 and VS 2005 for web application project and lately i am noticing that .designer.aspx.cs does not declare all the controls 'automatically' which r there on .aspx...i add them manually and some of them get lost,like the additional 'div' controls which i have on pages inheritated from the master,everytime i reload it.. ..i fully understand that i am not suppose to manually change anything in designer.aspx.cs but what do i do with this issue? Is .net 2.0 ,VS 2005 are too obsolate and i absolutely need to get on .net 4.0,2010..
firstly a static class only ever exists once and is not an instance. Any static members (ie static int NoOfPeople;) is stored in one place and is shared between all sessions (like the old global variables). Now static methods is where i'm not 100% sure. If I have a static method that doesn't use any other static members could this cause inconstant results, example (this is a fairly pointless method but just a quick example of the top of my head)
[Code]....
So in this example if two sessions (or threads) were to call this at the same time - would they both get back the expected results, because the method only uses private data (a, b and totalToReturn).Im sure this sounds a little simple but I will be using static methods to build user objects and various other objects that there will have to be a 100% garentee that the objects will not get mixed up between sessions and the wrong things return to the user.
I created user control. It exposes string[] public property (it may be List<string> or whatever). I want to support defining this property in aspx code, when declaring the instance of this usercontrol. Something like this:
i would like to know if there's something wrong in this asp.net code:
mydatareader = mycmd.executeReader() if myDataReader.HasRow then // Do something end if myConnection.Close()
If i avoid to call a "MyDataReader.Close()" does the connection close anyway ? I ask this because i'm assuming that if call a "MyConn.Close" it automatically close the associated datareader... or am i wrong ?
I got any error from the code, saying 'not all code path return a value', i suspect it is the catch block doesnt return a value. If so, what value should i return?
i have 5 methods in classA. each and every methods i have open the sqlconnection and close it, instead of that is there anyway to create a sqlconnection at one time if its opened then no need to create a new connection, if its closed then we have to connect.
I always use SqlConnection() To open a connection then use the connection to interact database. But I have heard somewhere that opening SQLconnection() take a time. and if on different pages of projects I repeatedly Connect database then It will take long access time always. So I want to know that if there is any other methods which don't use the SQLConnection to interact database and increase the response time of database.
so i have the function below in a webservice. and it works, but when i try to copy it to aspx page code behind, i get the message in the subject. Can someone tell me if the function below is valid? One of my project uses it and it works.
in my application when i type sqlconnection it is not showing any intellisence, i added the namespace System.Data.Sqlclient not only sqlconnection even i am not getting Page calss can u help me.actually i am sharing this application from my company server.
in our company previously there was .net 2.0 frame work when this project was developed(one year back). yesterday our company installed 3.0 .net frame work is this any problem for previous project which are developed in 2.0 how can i go through this problem.
I have a gridview, where I have made autocode using the wizard. However I need a dynamic SQLcommand from server side. I have tried this code, but it doesn't work, it works if I use this code from HTML (setting the sqlcommand in the SQLDataSource. I have deleted the sqlcommand from the HTML and instead I have implemented the code in the page_load event:
Code:
Dim str As String = SqlDataSource1.SelectCommand = "SELECT DISTINCT Beregning.bId, Informationer.Dato,Beregning.bType, Informationer.pNavn, Informationer.pNr, Informationer.Beskr, Beregning.uId FROM Beregning CROSS JOIN Informationer WHERE (Beregning.UserId = @UserId) AND Beregning.uId = Informationer.uId AND (Beregning.bType=@berType2) ORDER BY Beregning.bId DESC" SqlDataSource1.SelectCommand = str But this code works, when I apply the SQLCommand in HTML:
I have another class that creates the connection (see refined class half way down page) and I believe it connects or at lest I do not hit any of the exceptions in run time.
I would now like to insert data into my database but nothing is updated.
I am trying to follow this example but it is for reading.
I did run "querystring" on the show SQL Pane and it does execute correctly. It inserts data properly as a new row.
a) SqlCommand.ExecuteNonQuery is used for update, insert and delete operations.
Besides the fact that by using ExecuteNonQuery instead of ExecuteReader we automatically know there won't be any query results returned, are there some other benefits/reasons why ExecuteNonQuery should be used?
b) Similarly, if we want a database operation to return a single value, we should use ExecuteScalar instead of ExecuteNonquery ,where with the latter result would be returned via SqlParameter. Is there any particular reason why we should prefer ExecuteScalar over ExecuteNonQuery?
i would like to write a streaming programming which will keep updated or query the database. I would like to use a connection instead of open and close connection on each transaction. But the streaming programming would not end, running at all the time. So, is it any effect if i am using only one connection (within a long period). Such as performance, timeout issue, or others exception.
