I have a formview which displays a recordset based on a parameter supplied by a dropdownlist. The formview has "AllowPaging = True".
The first time the dropdownlist is changed, the formview shows the (correct) first row of the retrieved recordset but the paging controls are missing. From that point on, when the dropdownlist is changed, the formview works as expected, showing the correct page controls.
What do I need to do to have the formview show the page controls the first time it is activated?
These kind of errors are sometimes due to a missing explicit binding call such as:
formview.DataBind();
Try this after the first change of the dropdownlist.
Related
I have an asp page with a GridView control. One of the columns in the grid view is a dropdownlist. the drop down list are filled using the RowDataBound event on the page load event. However, one of the options in the list, when selected, will popup a dialog that will allow the user to add a new item to the list, and that newly added item becomes the selected item for that drop down. This part I have working fine, but I want to be able to add the new item to the drop down list for every row in the grid. How do I, in a way, re bind the drop down list in all rows after the page has loaded without having to loop through each field?
If all the DDL's have a shared DataSource then it should just be a matter of forcing a postback after adding the new listitem. But how are you adding the new listitem?
If your popup is simply adding a new html <option> tag to an html <select> tag, this is not the same thing as updating the DDL DataSource.
For all the DDL's to show the new listitem your popup would have to perform a postback that updates the DDL datasource(s) and all the DDL controls in the GridView would need to be rebound.
This would happen automatically on a postback assuming that the DDL controls are connected to their datasource via the DataSourceID property. If you are making use of the DataSource property then you will have to call DataBind() explicitly for each DDL control, which I think you said you are doing in the GridView RowDataBound event.
Alternatively you could loop through all your ddl controls clientside and add the same item to each control, but you would lose all those changes the next time the page refreshed and I don't think that's what you want.
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 have a couple GridViews that are dynamically created and placed into a PlaceHolder. When I mouse over the Select button, it shows __doPostBack('ctl00$bodyPlaceHolder$ctl0X','Select$Y'), where X = what I think is the GridView/Control index for the page and Y = row number of that GridView.
Since it is dynamically creating the GridViews, it makes sense that names them ctl0X, but on the PostBack how do I use this information?
I wouldn't even have this problem if adding the SelectedIndexChanged EventHandler worked, but it never gets called.
I found one other question like this, but the answer involved adding a GridView within my GridViews, which would also have to be dynamic, which brings me back to the original problem.
Edit
Okay, so I set gridViewDynamic.ID = "blahblah" + r.LastName, thus giving each GridView a unique name, so on mouseover in the page I get __doPostBack('ctl00$bodyPlaceHolder$blahblahSmith',Select$Y, I still can't access the items on PostBack because they no longer exist. So, I added the same GridView creation code to an if(IsPostBack), then called GridView gView = (GridView)this.Page.FindControl(blahblahSmith). Great, gView isn't null. But all the data in the rows are. Calling gView.Rows[0] returns null.
Use Page.FindControl("TheNameYouGaveTheDynamicGridView")
GridView grid = Page.FindControl("TheNameYouGaveTheDynamicGridView") as GridView;
If you are using MasterPages, you need to take a different approach to find the control on the page, but it is the same premise.
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