Web Forms :: Passing Values - Theory And Practice?
Aug 6, 2010
Let's say we need to pass values around in the same page or from page to page in an ASP.NET 3.5 web app. The values do not need to be maintained after the user leaves the session. Our options include creating a Session state variable, a ViewState variable, or creating global variables in a standalone class.
Limitations
Session state variables can be passed from page to page but usually have a timeout limit. I think the default timeout is 20 minutes. So the value could be lost if the user walks away from their desk in the middle of something and doesn't return for half an hour.
ViewState variables can only be passed around within a page. Leave the page, the variable is emptied. Dropping lots of values into ViewState can drag down performance.
Global variables in a standalone class.???
Where are the values for global variables stored? Are the stored in Session state and subject to the same timeouts or does the app allocate memory space for these variables?
Here's an example of the global variables we were discussing:
[Code]....
View 4 Replies
Similar Messages:
Apr 28, 2010
If my web method throws an exception, what is the best practice for passing that exception to the client?
View 1 Replies
May 24, 2010
I populate web form with dynamic list of exams from database. I want user to enter examination marks for each exam. There is list of exam titles and textbox near each title.I create list with repeater control (ViewState is disabled)
class Exam
{
public int Id { get; set;}
public string Title { get; set;}
}
...
// this list is retrieved from database actually
Exam[] Exams = new Exam[]
{
new Exam { Id = 1, Title = "Math"},
new Exam { Id = 2, Title = "History"}
[code]...
View 1 Replies
Mar 18, 2011
I wanted to know if we can pass values from Parent page (in this case from Default.aspx page) to the user control and maintain those values on subsequent "Add/Load" of user control.
So in short, if I click the "Add" button it loads my "webusercontrol" and also I am able to pass my default.aspx dropdownlist value to this dynamically loaded user control and assign it to a "Label or Textbox" which resides in my "webusercontrol", now the problem is that the value doesn't persists! What I meant is , when I click "Add" button again the "webusercontrol" gets loaded again perfectly but now all my "Label's" in webusercontrol has the new selected value from the default.aspx dropdownlist.
So say for instance I have a Dropdownlist in Default.aspx page with Values "Apple, BlackBerry, Nokia" and initial value to be passed is "Apple", I click the "Add" button, now my "Label" inside webusercontrol has the value "Apple", perfect! Next when I click "Add" button again and select a different value to be passed this time say "BlackBerry" now I have 2 webusercontrol loaded on the page, so that means I have 2 "Labels" with different ID's, but now my first Label initially had the value "Apple" because that's what I had passed and now when I passed the value "Blackberry" both the labels of my webusercontrol has the value "BlackBerry" instead of one being "Apple" and another "BlackBerry"
Is there a way to resolve this issue? may be Dictionary List?
View 3 Replies
Feb 5, 2010
In general terms, which way will require more server processing power and which way will return faster queries... if there is even a difference. The client's database is still on the dev MS SQL server but is essentially but the client has decided they want to collect two more fields of information. Both fields are going to be collection text data and probably varchar(300) will be sufficient for the column data types. Would it ultimately be more efficient to
Add two additional columns in the main table so the data is entered directly into each record, or Add an additional table (or two) with a foriegn key to the primary table that holds the info for each new field The SELECT statement for the main table could be modified to either add the new columns (a.NewColumn1 and a.NewColumn2) or it could contain nested SELECT statements that pull in the data from the other tables. Custom daisy-chained Insert or Update statements would be no problem and a cascade Delete relationship would take care of any deletions. I'm just trying to figure out which would be better from a performance standpoint?
View 3 Replies
Oct 5, 2010
[Code]....
How can i get the selected item in de dropdown menu in form one, ofter the button submit in the form two is clicked?
View 5 Replies
Feb 22, 2010
i want to pass values between forms. wat i did is, I have textbox, a button in form 1 and a label in form 2
1. Created a property to return text of textbox in form 1
2. in form 2 i added previouspagetype and virtual address then i tired to access the property (label.text = previouspage.propertyname).. but no success..
i tried to loop through all controls in previous page to get the value but still its not working.. i wan a simple way.. without using sessions, cookies or anything..
View 19 Replies
Jan 30, 2010
I am building a webpage and getting the values entered in textbox from the use now I want to use the values on the next page and want to display the values overthere... I'll explain in detail:
I have a form like below:
Now I want to redirect the user to another page on button click and then use the values of this textbox.
View 11 Replies
Feb 8, 2011
i have to pass a value in the textbox in one application to another one in run time. Two web application resides in the same Solution. how can i do it?
View 9 Replies
Feb 2, 2010
How to send values from page1 to page2 in ASP.NET,
View 6 Replies
Feb 2, 2011
I am able to transer the single value to another page(Pop_up) using following code i wanted to pass one more value to another page how can i add to following code.
status.aspx
<script type="text/javascript">
function OpenPopupLLP() {
window.open("LLparts.aspx?strWorkOrderNumber=" + document.getElementById("txtWON").value,"List", "scrollbars=,resizable=no,width=800,height=550");
return false;
}
LLparts.aspx
<script language="javascript" type="text/javascript">function GetRowValue(){
var val = window.opener.document.getElementById("txtWON").value;
document.getElementById("lbl1").innerText = val;
document.getElementById("txtWCON").innerText = val;
}
<body bgcolor="#ffcc66" onload="GetRowValue()">
form_load
txtWCON.Text = Request.QueryString("strWorkOrderNumber")
View 2 Replies
Sep 3, 2010
I have two user controls attached to my Master page. (vb.net)
These user controls display ads, and the pnly difference between them is the width of the ads they should diplay.
Is there some way in which I can just register one user control, but use it twice, and then pass different integers to them?
In other words, instead of having this:
@
Register
Src="Ads240.ascx"
TagName="Ads240"
TagPrefix="uc240" %>
[Code]....
but kind of send different values to them (like "Usercontrolparameter=120")
I have looking at properties and the like, but I don't know if they can let me reuse the user control file with different values.
View 3 Replies
Oct 8, 2010
I have a problem I have been googling the entire day and still have no soloution. I have a detailsview with 2 dropdownlists. Fisrt one is ddlCaregory. Second is ddlSubCategory. The value is passed from the first ddl to display the SubCategory linked to ddlCategory. Both ddlCategory and ddlSubCategory are Templatefields. This is also in VB.
The Details view has a sqlDataSource (sdsApplicants), ddlCategory has a Datasource (sdsCategory) and ddlSubCategory (sdsSubCategory). ddlCategories lists the data returned from sds Categories and save any changes to sdsApplicants. I can get ddlSubCat to display the correct SubCatagory bases on ddlcategory sesection but as soon as I try bind it to sdsApplicants I get the following error
'ddlSubCategory' has a SelectedValue which is invalid because it does not exist in the list of items.
Parameter name: value
View 4 Replies
Mar 9, 2010
Let's say I have DropDownList ddlRooms bound to the datasource which returns list of available rooms from table tblRooms. On the other hand I have users, and their info is stored in table tblUsers. Using FormView frmUsers can be inserted, edited and updated... frmUsers is be bound to separate datasource. To each user, I would ilke to assign a room, so the value of txtUserRoom will be populated based on the selected value from ddlRooms. How can i pass the selected value of ddlRooms to txtUserRoom while keeping txtUserRoom stil bound to user datasource? Do I need two separate fileds or can i just put value of ddlRooms into datasource user?
View 3 Replies
Mar 10, 2010
I am exposing state_v value by using property in aspx.vb page..How can I create an instace of the page in User control to access this property...mypage.aspx
<%@ Register ........%>
<div>
<asp:dropdownlist ID="ddl" runat="server"></asp:Dropdownlist>
[code]...
View 2 Replies
Feb 11, 2012
If a value is stored in a session object. How do I retrieve the session value in a function in javascript. I tried
var background1 = '<%=Session["test"]%>'
But I get blank
View 1 Replies
Dec 28, 2010
I've a form containing 30+ textboxes. I'd like to save the data entered in the form texboxes in an object(session) and pass them into another page and simply display the values in a tabular form. How can i do that. Also, suggest me the best way to do it.
View 7 Replies
Jul 14, 2010
I have a windows form control which is hosted inside an Asp.Net page.
Is there a way to pass value from this control back to the Asp.Net page. I have tried using
"document.forms[0].UserControl1.publicProperty" where publicProperty is a publicly defined property in the control but it is giving undefined.
[code]....
View 1 Replies
Jan 7, 2011
I have a page that contains a few user controls which all use an id in a querystring. I want to change this so that the page can send the id to the user control and can call a function on the user control.
Also is it possible for the user control to get the id from the page or a control on the page as its parent?
View 8 Replies
Apr 7, 2010
I have a web form that has drop down controls. These controls are data bound to a database. Now, I would like the results of the selected values to be shown on a new aspx page in a gridview or detailsview.
View 3 Replies
Nov 2, 2010
In this datelastmodified is Datagrid Column Name. I m displaying that column value in DIV. Now, I want to display another column Value in that DIV. that column name is Document Type. May I know how to pass that value.
[Code]....
View 1 Replies
Jan 4, 2011
This is an ASP.NET 3.5 web app written in C# using VS2008 and connecting to an MS SQL backend. It is using ad hoc queries in a strongly typed dataset to pull from the database. This query (shortened for clarity) is designed to allow optional input of parameters (a requirement) or pull all records if no parameters are input. It works normally in SQL Server Management Studio with the addition of Declare and Set statements and it works normally in the TableAdapter's Query Builder:
[Code]....
The markup contains this ObjectDataSource, which is tied to the TableAdapter with the above query:
[Code]....
The problem I'm having is in passing null values to the ODS to feed to the query. Tying the ODS parameters directly to the dropdownlists and textboxes didn't work. Got an error message that there was a mismatched data type. Tried several combinations of code to feed the right values to the ODS parameters but couldn't find one that worked. Is the problem in the query or am I setting up the code-behind wrong? Here's the code:
[Code]....
View 9 Replies
Sep 26, 2010
For efficiency's sake I've created a number of stored procedures to run against an SQL table. Which procedure runs depends upon the checkboxlist choices a user makes before clicking a button. The checkboxlist looks something like this:
<asp:CheckBoxList AutoPostBack="True" runat="server">
<asp:ListItem Enabled="True" Value="1">Item 1</asp:ListItem>
<asp:ListItem Value="10"> Item 2</asp:ListItem>
What I can't figure out is how to loop through the checkboxes in the Button1_Click event in the .cs code behind page to add up the values of the selected items. (The value of an unclicked box being 0.) Converted to a string, the totaled value is then appended to a stored procedure name (MyPROC) for entry into the SQL statement. In other words, if the user clicks just Item 1, then the Button1_Click event would produce a stored procedure name of MyPROC1, insert it into the statement, and fire off the query; if Item 1 and Item 3 are selected, then MyPROC101 would be called.
My second question is: how do I place the concatenated string into the SQL statement?
This might all seem a bit unorthodox, but given the number of variables going into statement, it seems to this newbie the best approach.
View 4 Replies
Jan 10, 2011
I have a gridview, which has columns has ChildID,ChildName, course.
In the gridview, i have a radiobutton, which will select one of the rows at a time.I have a button in the page(The button is not related to the gridview). After selecting a row in the gridview, and when the user clicks on the button, i want to pass the data selected in the grid to the button.
The button is used to redirect users to other pages. so i want to use the columns as querystrings to pass to the page. I dont want to use the hyperlinkfield attached to the grid.
View 2 Replies
Dec 28, 2010
I am having a formview control with paging enabled. It's a simple page used for viewing pictures. (It's from the personal web site starter kit with some modification)
[Code]....
I would like the formview to pass not only the pageindex value but also the Next or previous picture's unique ID called in my case PictureID?
View 3 Replies
