How to select top n rows from a datatable/dataview in asp.net.currently I am using the following code by passing the table and number of rows to get the records but is there a better way.
public DataTable SelectTopDataRow(DataTable dt, int count)
{
DataTable dtn = dt.Clone();
for (int i = 0; i < count; i++)
{
dtn.ImportRow(dt.Rows[i]);
}
return dtn;
}
I need to retrieve data from DataView/DataTable. I need to retrieve the top4 records, then, 5th - 10th recoed.
This is how I do this, but I am looking for a clean code, doing it correctly:
[Code]....
I have one big DataTable with X rows. I want to select Y rows from it and bind them to a new ViewList. While doing it, I want to delete these rows from the DataTable (Having X - Y rows).
What is the best and fast way to do it?
I don't know if it is better to create a new DataTable to have the Y and after that bind them to a ViewList or something else?
I'm also looking for example in code how to select/delete rows from DataTable.
i could bind the data form tables to dropdownlist in asp .net using linq.
ex:
var res=from n in dc. contacts where n.location==Hyd select new{n.Id,n.Name};
var res1=from n in dc. Morecontacts where n.location==Hyd select new{n.Id,n.Name};
dropdown1.Datasouce=res;
dropdown1.DataTextField="Name";
dropdown1.DataValueField="Id";
[CODE]...
I have a ListView with Checkbox. My requirement is - When I click on any checkbox then it should return all the columns values of that row on behalf of that CheckBox. After much study I came to know that using DataTable and DataRow I can get all data of particular ID of a Row. But I am unable to work with this. My code is something like below:
Â
DataTable dt=new DataTable();
dt=objBAL.Get_ShoppingCartData();
ListView1.DataSource=dt.Tables[0];
[Code].....
 I have records in database as
Â
hotelid        amenitieid
17774 Â Â Â Â Â Â Â Â 7585
15636 Â Â Â Â Â Â Â Â 7585
25363 Â Â Â Â Â Â Â Â 7585
36933 Â Â Â Â Â Â Â Â 11236
21412 Â Â Â Â Â Â Â Â 45696
23521 Â Â Â Â Â Â Â Â 65474
15636 Â Â Â Â Â Â Â Â 65474
21412 Â Â Â Â Â Â Â Â 65474
now in above, if i want only those hotelid where amenityid is 7585 and amenityid is  65474 and not any else hotelid ,  then how to use select query in datatable  in asp.netÂ
When i try to sort my table manually, i receive this error:DataTable must be set prior to using DataView.The code is:
protected void GridView1_Sorting(object sender, GridViewSortEventArgs e)
{
DataTable sourceTable = GridView1.DataSource as DataTable;
[code]...
I need to handle a datatable or dataview in the code below
private
void SetListDataSource(ListControl
lc, DataView d,
string valueField,
string
textField)
[Code]....
HOW TO specify which columns are in a DataView from a DataTable. I want to create a DataView, that only has the columns from a DataTable that I choose, and in the order I want.
Example:
// DataTable_MyTable ~~ Column #0 is for ID. I do not want my view to get this column.
// DataTable_MyTable ~~ Column #1 is for TYPE. I want this column to come in 2nd place in my view.
// DataTable_MyTable ~~ Column #2 is for NAME. I want this column to com in 1st place in my view.
DataView DataView_MyView = new DataView(DataTable_MyTable ~~ some how only get the columns I want, and in the order I want ~~);
// DataView_MyView now has only 2 columns.
// DataView_MyView ~~ Column #0 is NAME.
// DataView_MyView ~~ Column #1 is TYPE.
How could I parse a Json string with all the data from my table to a DataTable or a DataView?
View 5 RepliesI am trying to do something I thought would be simple but something isn't working for me.
I have a DataTable that I need to sort by a price ascending, then select an 'nth' row value. The 'nth' value is the row count/10.
[Code]....
What happens is I get the "nth" value from the original tblDeals.
I want to check that the row index I specify is below the row count so it doesn't throw the error
Index 2 is either negative or above rows count.
how would I achieve this with my code?
Using connection As New SqlConnection(connStr)
Dim command As New SqlCommand
command.Connection = connection
connection.Open()
Dim a As New SqlDataAdapter("SELECT top(3) name, (SELECT TOP (1) ImageId FROM Images WHERE(productid = products.Id)) AS imageId FROM Products WHERE beginnerdiscount = '1' ORDER BY Dateadded", connection)
Dim s As New DataSet()......
How to display Top 10 Records using DataView Or DataSet, Below is my code. I am using .net 2.0 and i don't want to Modified in my SQL query.
Dim ds As New DataSet
ds = tv.GetSearchLatestEvtHosting("", "", "", "", "")
Dim dtvCust As DataView = New DataView(ds.Tables(0))
I have a json service method that returns an object with two properties. The first property is called Rows and contains the list of objects I want to bind to the dataview. The second property is TotalRowCount. It is a paging method. How can I tell the DataView to bind to the Rows property? This is what I have so far...
[code]....
I am doing GridView Sorting without ObjectDataSource. For this requirement I need to convert DataTable to DataView, I know I can do that in VS 2008 but How can I do this in VS 2005.
View 20 RepliesI have one gridview and i want to take all the values in a datatable or dataview.
I tried like this
DataTable gridTable = (DataTable) dataGrid1.DataSource;
but gridTable is showing null, it should not show null because gridview has lot of records with 3 columns
Is there any way i can convert/store a gridview.Datasource records in a datatable or dataview?
I need to expose a Web service which will provide an array/DataTable of 20 rows (average) of data - certainly no more than 100 rows would ever be needed. The largest item in these rows would be a date.The Web service would be called by a separate Web site in order to display these 20 (approx.) rows in a GridView/DataView. I would have to be able to dynamically choose which domain to go to and find the Web service.I would possibly have to secure the Web service with a password but this is not vital (possibly with soap headers over https).
My question is what technologies should I use to create this Web service? I know enough about .asmx Web services to struggle through and get this working, but should I get a book on WCF and learn that instead?I use AJAX and jQuery so am also wondering if I should be using one of those client side, to call the Web service and populate the grid?
I have a page which lists all the files in a particular folder (all PDFs), using a data-table and gridview.
I'm currently sorting this table by the filename (by using a dataview), which isn't that helpful, and I want the gridview of files sorted by the file created or file modified date (as recorded in Windows).
If that's not possible, a second option would be to extract the date from the file name string (no problem doing that), and sort the dataview/datatable or gridview based on that. Example Filename: DailySalesReport-1-15-2010. My only hangup with this is how do I sort on date, when it's a string value? Convert to date? How would I sort the whole dataset based on this converted value?
[Code]....
I have a DataTable of available time slots. I have another DataTable of reserved time slots. I need to remove from the list of available slots the ones that have been reserved. The blocks are in 15 minute increments, but one of my problems is that the reservation can be longer than 15 minutes. I've had some luck removing one or two, but not all of the required columns.
Here's my code (it doesn't work right now).
[Code]....
I have a table that contains about 8000 records and I need to be able to select any given sequence of 250 subsequent rows by a specific row index of teh table...
how I can go about that easily using a dataview without building a secondary table and just pushing the records I need into it?
I'm trying to filter a DataView to return all the rows whose column x starts with a number: The following works in SQL Server:
select *
from dbo.Page
where Name like '[0-9]%'
However, when I try this:
dataView = new DataView( someDataTable, "Name LIKE '[0-9]%'", "Name ASC", DataViewRowState.CurrentRows);
I get "invalid parameter [0-9] with Operator Like" error message. What is the correct syntax to achieve my goal?
Dim dt As New DataTable Dim da As New SqlDataAdapter(s, c)
c.Open()
if Not IsNothing(da) Then
da.Fill(dt)
[code]...
When I call da.fill I am inserting all records from my query. I was then hoping to filter them to display only those where the GroupingID is equal to 0. When I run the above code. I am presented with all the data, the filter did not work. Please can you tell me how to get this working correctly.
I came across a situation where a user selects no of rows from dropdown , depending upon the user input, automatically that no of editable rows should appear to input data...(maximum 8 rows only)
View 1 RepliesI have a gridview which right now is getting loaded with four pages of data. There are 50 rows per page. My problem is I need the "select all" button on my page to select 180 rows, not just the 50 on the page. This is my javascript:
Code:
function sel() {
var frm = document.forms[0];
isSelected = !isSelected;
for (var i = 0; i < frm.elements.length; i++) {
var e = frm.elements[i];
if (e.type == 'checkbox' && e.name.indexOf("ckSelected") > -1)
e.checked = isSelected;
}
}
I am more a C# person than javascript, but I am deducing that I need something other than document.forms[0] to represent the entire gridview. Or perhaps, I can't do this in javascript at all. Do I need server code to run and set a session variable, then when the user clicks the button to do something with all his selected rows (it goes to a detail page), query that session variable to see if it's all rows instead of iterating through each gridview row individually to see if the checkbox is checked?
I have developed a website in asp.net 2.0 with backend MS SQL server 2005. After each 2-3 days when i try to login to my admin panel i get a /server application error "datatable must be set prior to using dataview ".When I made a research on this i found the error is in the caching part of the code where i am using a dataset to fill my dropdown lists. But I am using the same code everywhere and on other place i didn't get any error but on a specific page. i usually get error when i try to login to admin. After successful login i redirect the admin to a page adminBazaar.aspx. and the error is always thrown by dis page only.other pages with the same code are working fine and there are no issues.I am using SqlCachingDependency. but can't figure out how to solve the problem.Right now to solve this I have to go to the server stop the website,then stop the application pool and the restart both. We have created a separate application pool for the website.
View 4 Replies