DataSource Controls :: How To Select Data With Linq And Bind To A DDL
Jan 5, 2010
I am trying to select data with Linq and bind to a DDL. The custid field allows duplicates in this table, but I only want unique values in the ddl. I tried the following code:
[Code]....
The use of "Select Customer.CustID", with or without the Distinct, causes this runtime error. CustID is a valid field in the table, and it shows up in intellinsense and compiles. If I just Select Customer, the error goes away, but Distinct doesn't know to look for distinct custid's.
DataBinding: 'System.String' does not contain a property with the name 'CustID'.
i have a DAL function to get the records from DB. it will return a dataset. now i want to use linq from dataset and bind the dropdownlist, gridview data comtrols. pls any one give me a sample. also i want to know whether we can use distinct, fileter in linq.
There may be a lot of data in the Blogs table. What if all I wanted was say BlogID, BlogTitle and BlogAuthor and nothing else, is there a way to do this in an effort to make the sql more efficent?
Along the same lines in my DataContext (.dbml) file I added some associations between some of my tables. This makes coding nice when I do a linq statement that will join those tables automatically for me but my concern is does it do that everytime, thus making all my linq quieries inefficient?
I have a basic CMS which I'm adding to a site to display some downloads organised into groups. I have two tables, one for the groups and one for the downloads. I'm using a repeated to display the groups with another repeater inside to display the children. This works perfectly.
However some of my download groups may not have any downloads related to them and I'd like to handle this by filter the groups so that only those with a relate download record(s) are shown.
I'm trying to do this with the query which populates the top repeater based on some ideas I read but I must be going wrong with the syntax.
Here is what I'm using to try and only select downloads groups which have downloads linked to them by the download group ID.
[Code]....
Can anyone offer any thoughts on how I should construct the query to perform this?
I have connected listview by using datasourceid that means by using "sqldatasource1" now i want to change value of listview at run time according to search so for that i am using datasource at codebehind. but it give an error
"listview have already bind with datasourceid you can not bind it with datasource"
I am trying to create a multi column listbox by combining fields in Linq select statement, as Let Name = Last + First. The problem is how to pad the Last column with spaces as you would in SQL using REPLICATE so when I bind the listbox to the data, it looks like two columns.
i my website i am using Repeater control which further contain checkboxlist control. Now my problem is that i have successfully bind "Parameter Type" in repeater control but when i am binding checkbox values, it does't appears in display
<asp:Repeater ID="Repeater1" runat="server"> <ItemTemplate> <h4> <%#Container.DataItem%></h4> <asp:CheckBoxList ID="chkParList" runat="server" RepeatDirection="Horizontal" DataTextField = > </asp:CheckBoxList> <br /><br /> </ItemTemplate> <SeparatorTemplate> <hr /> </SeparatorTemplate> </asp:Repeater> In *.cs file following are my code IMonitoringDataInfo objMonitoringDataInfo = new ChannelFactory<IMonitoringDataInfo>("MonitoringDataInfo").CreateChannel(); Collection<ParameterDetailDTO> clParameterDetailDTO = objMonitoringDataInfo.GetAllParameters(idList, out errorCode); var parameters = (from resx in clParameterDetailDTO select resx.ParameterType).Distinct(); Repeater1.DataSource = parameters.ToList(); Repeater1.DataBind(); counter = Repeater1.Items.Count; while (i < counter - 1) { foreach (var parType in parameters) { var items = from resx in clParameterDetailDTO where resx.ParameterType.ToLower().Contains(parType.ToLower()) select new { resx.ParameterName, resx.ParameterID }; ((CheckBoxList)(Repeater1.Items[i].FindControl("chkParList"))).DataSource = items; ((CheckBoxList)(Repeater1.Items[i].FindControl("chkParList"))).DataTextField = "ParameterName"; ((CheckBoxList)(Repeater1.Items[i].FindControl("chkParList"))).DataValueField = "ParameterID"; ((CheckBoxList)(Repeater1.Items[i].FindControl("chkParList"))).DataBind(); } i++; }
I'm new to Linq. I have searched and searched the web for a soluion, and can't find anything. I have a Linq query and I want to insert a row ("Select User") to the top before I pass it to the drop down list. I've been trying to use the Union but to now avail (it keeps telling me that my object doesn't support the Union method). My code, prior to attempting to inser a row, is very simple.
public SelectList DropDown_Users() { var context = new VivarianDataContext(); var query = from t in context.AspnetUsers select new { t.UserId, t.LastName }; list = new SelectList(query.AsEnumerable(), "UserId", "LastName"); return list; }
Now I try to insert a row and I found this on the internet and it seems to say that his solution will work. But it is filled with syntax errors. [URL]
I tried to implement it using the following code, but it doesn't compile.
public SelectList DropDown_Users() { SelectList list; //get the original data var context = new SQL2005633131VivarianDataContext(); var query = from t in context.AspnetUsers select new { t.UserId, t.LastName }; //create a dummy table with an empty row var AllUsers = new List<AspnetUsers>(); var BlankUser = new AspnetUsers() {UserId=System.Guid.Empty, LastName="Select One"}; AllUsers.Add(BlankUser); //use Union to join the data - ERRORS HERE var newTable = AllUsers.Union(query); list = new SelectList(newTable.AsEnumerable(), "UserId", "LastName"); return list; }
i wants to display the related informations of each record of dataset. That mean, dataset having rows for A,B,C and etc..
Then i wants to display the information in same Gridview of each record(A,B,C). i wrote the below my coding, it dispaly info of the last row of dataset only. pls correct the coding.
There are multiple child nodes coming from Database in Treeview. Also, there is a DataGridview.
I want that when I select/click any of the child node from TreeView, it should show the related data(of selected child node) in DataGridview from Database on "Page Load".
My current code is below, which only binds all the data in DataGridview and Treeview from Database:
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";
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.net
I have two Data Table, One data table contain Product-A information, and another data table contain Product-B Information, I want to get the uncommon values between the two data table, I would like to achieve this using LINQ, find the sample values below
Product Data Table Product-A-Id ProductName W10012 A W10013 B W10014 C W10015 D
Sales Data Table
ProductId ProductName W10013 B W10013 B W10015 D X10020 AC
I want to find the uncommon data from both data table using LINQ, So find my expected Data Table result is
Result Data Table ProductId ProductName W10012 A W10014 C X10020 AC
The drop down list is used to determine what search criteria will be used to find an invoice. I tried to set the Select method in the switch statement. I don't understand how to set the Select Method and the select parameters programmatically though . I tried a few different ways but can't make the compiler happy. My ODS is in scope in the code behind. I'm not able to access it's properties though. The BAL resides in a separate project that is a ClassLibrary. I also have a using statement for the ClassLibrary project in the code behind.
Before i talk about my situation or problem let me tell you all that i'm new to ObjectDataSource, ListView.
i've following controls
Three LinkButtonOne ObjectDataSource Control (which is binded to custom Business object) . Paging is enabledListView (This is binded with ObjectDataSource Control)
Requirements:
By default ObjectDataSource should be bounded to DataSource A, thus the user should see on page load the default data from DataSource A.When user Clicks on respective LinkButton, the ObjectDataSource should now be binded to new DataSource B, thus the user should now see data in ListView from DataSource B. The same should happen with LinkButton C respecctively
