I've got a bit of an chicken and an egg.
I need to bind a gridview to a set of database values. The gridview is dynamic and the columns, cells are created at run time.
As such, I need to re-bind the grid on every postback in the pre-init, init events after very post back.
However, the data used to populate the grid uses a value from a dropdown box on the same page. As such, the value of dropdown is not accessible through viewstate until after the init event (i.e. the selected index is always the first item in the list until after on init).
How can I get access to the value of the drop down in time to rebind the grid before the pageload event?
If the Gridview always has the same number of columns, you could have the dynamic query generate column names as aliases, and then just rebind the Gridview on dropdown change?
you can use and HtmlHidden control for store the value you need. It doesn't depend by the viewstate and it's available into the page init
Related
I've inserted multiple rows data from gridview to database at a time using stored procedure.
Now I've to fetch and display that multiple rows data into GridView and inside GridView I need to call particular value from column to a particular label into GridView.
How can I get that values dynamically? I am not seeing any way to show data.
Create a class structure. This class is passed in and defining variables for the value. Define a list of this class type. Add the individual values from the database to this list. Assign this list variable to the GridView's Datasource
There are tons of articles out there just go and have a try.
Databinding
Secondly, you mentioned
I need to call particular value from column to a particular label into
GridView.
I mean on when? after binding or there should a button and it's click event do that stuff?
I am working on a master/detail gridview and detailsview in asp.net web forms using an objectdatasource. The details view is displaying extra information about the selected row from the gridview. When I sort the grid, I want the currently selected row, before sort occurs, to remain in the details view after the sort is completed. Instead, the gridview is auto selecting the new first row whenever I sort.
I found a partial solution to this problem. If I set WhateverGridview.SelectedIndex= -1 onsort and the value becomes null. This makes it deselect any rows after a sort. This leaves the details view blank. However, what I want to do is maintain the selected row not nullify it.
So, does anyone have a good way to retain the selected value or prevent the details view from displaying after sort event fires.
Here you need to use the GridView.EnablePersistedSelection property. Set this property to true.
Setting this property to true means that GridView will make sure that the selection of a row is based on data-key values.
By default GridView makes row selections based on index. This is the reason why when you sort, gridview is selecting row based on index and you lose your actual selected row.
I am working on asp.net user control. I have used a gridview and a formview control.
on selecting a row in gridview it will hide the panel containing the grid and will display the panel containing the form view which is using the Grid's selected value as its key value and form loads in edit mode. for some extra use i had to place a checkbox list control in my form view control. and used SQL datasource to fetch data from databese to chkbox list. and used the same data key as formview control. Now my form view control works properly but my Checkbox list is not working properly as it cant get the selected value from grid view.
Thanks in advance for help.
You should bind your CheckBoxList on the DataBound event of your FormView.
Since you would need the same data key, you could use the DataKey property of the FormView.
If any additional data fields are required, you always have the DataItem property.
Done in this order, your CheckBoxList should work as expected.
I used a session variable and it worked for me.
i used a session variable to store the selected value of grid in its selected index changed event and then used it as key value in checkbox list.
So I'm currently working with a C# ASP page in which I have a DropDownList and a GridView. I'm initializing both the GridView and the DropDownList (Along with their connected data sources) in the PageLoad event.
I've got the DropDownList set to AutoPostback=true. I'm changing the select statement for the GridView in the DropDownList_SelectedIndexChanged event. The end result is that the page loads again and then the select statement is changed, by which point the GridView has already loaded again. This basically means that it the GridView changes take two page refreshes to update.
Is there a way to avoid having to refresh the page twice? I tried simply updating the DataSource and the GridView in the Page_LoadComplete function instead but by that point it was too late to update the page this time around, meaning it still required another refresh.
So you may try this in your page load....
if(!IsPostBack)
{
// only then bind your grid View...
}
and in your DDL's selectedindex changed event bind your grid to what ever select result set you may want to bind to...
what this will do is, your grid view bind code will get executed only for the first time in your page load event...and on any subsequent postbacks you may cause with your dropdown...you can bind your gridview in the selected index changed event...this will avoid binding your gridview twice...
I am using a SelectedIndexChanged function for a combobox to update the content of my DataGridview item. I have the combobox data bound to keep track of it's currently selected record. However, when I changed the combobox index it updates the datagridview as if the selected value was the same. This means once I have selected a different index value in the combobox, I have to select it again to run the function with the proper value.
Am I missing something here? Do I need to call the check for the current datarow selected in the combobox before calling the SelectedIndexChanged function?
Sounds like the page life cycle issue, as the datagrid will be fired before the slected index change if its in the page load event. at which point the index wont have changed so the data will be the same.