I created an ASPX page with search controls to the left bound as controls for an AccessDataSource.
I want the data grid to be blank on the first calling of the page, but show the results for subsequent page loads.
I plan to achieve this by putting [pFirstRun] = False as my first WHERE condition with the parameter pFirstRun tied to the value isPostBack. How do I achieve this?
Alternatively, is there a better way to achieve this goal?
You can use the OnSelecting event of your datasource and so something like this for your code infront:
<asp:AccessDataSource ID="AccessDataSource1" runat="server" OnSelecting="AccessDataSource1_Selecting"/>
And something like this in your code-behind:
protected void AccessDataSource1_Selecting(object sender, SqlDataSourceSelectingEventArgs e)
{
if (!IsPostBack)
{
e.Cancel = true;
}
}
you could put the code where you do the databind() on the datagrid within a
if (!Page.IsPostback){}
Related
I have a feeling I'm missing something really obvious, I'm not able to capture the selected value of my DropDownList; the value renaubs the first item on the list. I have set the DropListList autopostback property to true. I have a SelectedIndexChangedEvent which is pasted below. This is NOT on the master page.
protected void ddlRestCity_SelectedIndexChanged(object sender, EventArgs e)
{
if (IsPostBack)
{
r_city = ddlRestCity.SelectedValue.ToString();
}
}
Here is the DropDownList control:
<asp:DropDownList ID="ddlRestCity" runat="server"
Width="100px" AutoPostBack="True"
onselectedindexchanged="ddlRestCity_SelectedIndexChanged">
</asp:DropDownList>
Thanx in advance for your help!
My off the cuff guess is you are maybe re-populating the list on a post back and that is causing the selected index to get reset.
Where is your DataBind() call? Are you checking !IsPostBack before the call? For example:
protected void Page_Load(object sender, EventArgs e) {
if (!IsPostBack) {
ddlRestCity.DataSource = ...;
ddlRestCity.DataBind();
}
}
Explanation: If you don't check for !IsPostBack before DataBind(), the list will re-populate before SelectedIndexChanged is fired (because Page.Load fires before child events such as SelectedIndexChanged). When SelectedIndexChanged is then fired, the "selected item" is now the first item in the newly-populated list.
What is r_city?
If it's a textbox, then you need to do something like r_city.text = ...
Also -- you might consider removing your postback check. Usually, that's most useful in the page.onload event, and usually, you're checking for if NOT ispostback...
using paging in grid view but as i go through pagess i need to click on page links.. it should work on single click .. but it goes other page only after double click... any idea why..
simple and working
protected void grd_receipt_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
grd_receipt.PageIndex = e.NewPageIndex;
grd_receipt.DataBind();
}
simply call the databind after
Make sure your code to call DataBind() on your grid is in it's own method. You'll need to call it in two places.
On Page_load, if !IsPostBack, bind your grid.
When you're paging, set the new page index, then bind your grid.
This will eliminate your problem.
Although, questions somehow similar to this have been asked for a number of times, but the question is still unsolved. Here is the question:
I have a GridView which is contained in a tab container AJAX control which itself is inside an UpdatePanel. Gridview works excellent and its corresponding methods are fired accurately, but when I enable paging(e.g.) after I click on page 2, the GridView hides itself. here is my PageIndexChanging() method:
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView1.PageIndex = e.NewPageIndex;
GridView1.DataBind();
UpdatePanel2.Update();
}
Why paging causes GridView to stop working correctly? What can I do?
The solution is that you should refill the dataset which is used to populate the gridview, each time your page index is changed. By this way, you could ensure that in each seperate postback which has been triggered by the gridview page number, results will be populated.
I just tried that above code. I had same issue and now it is working just fine.
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView1.PageIndex = e.NewPageIndex;
GridView1.DataBind();
// UpdatePanel2.Update(); <-- Remove this line from your code.
}
I have GridView inside update panel. Did you write your event PageIndexChanging in your .aspx file also?
Hope this helps.
Further research:
http://msdn.microsoft.com/en-us/library/cc295545.aspx
Controls that are not compatible with UpdatePanel controls
The following ASP.NET controls are not compatible with partial-page updates, and are therefore not designed to work inside an UpdatePanel control:
GridView and DetailsView controls when their EnableSortingAndPagingCallbacks property is set to true. The default is false.
I had the same issue , changing the updatepanel property UpdateMode="Conditional" to UpdateMode="Always" and setting the property ChildrenAsTriggers="true" solved the problem for me.
To do it, you have to re set the datasource in the page index change event. The performance will be lower but that's the way you can make it works.
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView1.DataSource = ;//Set again the datasource
GridView1.PageIndex = e.NewPageIndex;
GridView1.DataBind();
UpdatePanel2.Update();
}
I´ve read most posts here but i can´t figure out why the "CheckedChanged" Event is not firing. Here is my situation.
I´m using a Repeater to generate Items out of a Database. Each ReapeaterItem should include an UpdatePanel, because i have to Update the Controls inside the UpdatePanel and do not want to reload the complete page. Inside these dynamically generated UpdatePanels (each RepeaterItem has one) i´m adding up to three Checkboxes dynamically (based on the Database). These Checkboxes need to fire the "CheckedChanged" event, because on some conditions i want to enable/disable/check/uncheck Checkbox1, 2 or 3 based on business logic. ... Hope you got this so far. I´m adding all Controls and have the EventHandler Added. But the generated Code does not reflect the Event Handler. I tried OnItemDataBound, OnItemCreated, PreRender, ... Events to add the Eventhandler too, but i was not able to find the CheckBox-Control with the ID.
I´m totally lost with this and on the way to use Buttons instead of Checkboxes. From what i read so far is that with Buttons i can use the CommandName from the Button and the ItemCommand-Event from the Repeater to get a workaround, but then i need to reflect the "Check" on the Page in some way.
btw, every Repeater (8) sits inside an ajaxtoolkit-accordion control.
Here i give you some Code:
aspx-Page
<asp:Repeater ID="RepeaterAccordionPane2" runat="server">
<ItemTemplate>
HTML Stuff<%# DataBinder.Eval(Container.DataItem, "Header")%>HTML Stuff<%# DataBinder.Eval(Container.DataItem, "Beschreibung")%></td>
<asp:UpdatePanel ID="UpdatePanel2" runat="server" UpdateMode=Conditional>
<ContentTemplate>
</ContentTemplate>
</asp:UpdatePanel>
HTML Stuff
</ItemTemplate>
</asp:Repeater>
Here is the Page_Load Part
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
dvAlleArtikel = new System.Data.DataView(...Database...);
[... some other code here ...]
RepeaterAccordionPane2.DataSource = dvAlleArtikel;
//RepeaterAccordionPane2.ItemCreated +=new RepeaterItemEventHandler(RepeaterAccordionPane2_ItemCreated);
//RepeaterAccordionPane2.PreRender +=new EventHandler(RepeaterAccordionPane2_PreRender);
RepeaterAccordionPane2.DataBind();
int nUpdatePanelIndex = 0;
foreach (Control crInRepeater in RepeaterAccordionPane2.Controls)
{
if (crInRepeater.GetType() == typeof(RepeaterItem))
{
foreach (Control crInRepeaterItem in crInRepeater.Controls)
{
if (crInRepeaterItem.GetType() == typeof(UpdatePanel))
{
LiteralControl litTabelleBeginn = new LiteralControl("<table width=\"100%\" border=\"0\" cellspacing=\"0\" cellpadding=\"2\">");
((UpdatePanel)crInRepeaterItem).ContentTemplateContainer.Controls.Add(litTabelleBeginn);
if (dvAlleArtikel[nUpdatePanelIndex]["ArtNr1"].ToString() != "0")
{
CheckBox CheckBox1 = new CheckBox();
CheckBox1.ID = dvAlleArtikel[nUpdatePanelIndex]["ArtNr1"].ToString();
CheckBox1.Text = (dvAlleArtikel[nUpdatePanelIndex]["CheckBoxLbl1"].ToString() == "" ? "leer" : dvAlleArtikel[nUpdatePanelIndex]["CheckBoxLbl1"].ToString());
CheckBox1.AutoPostBack = true;
CheckBox1.CheckedChanged +=new EventHandler(CheckBox1_CheckedChanged);
LiteralControl litNeueTabellenZeileBeginn = new LiteralControl("<tr><td width=10><img src=\"images/helper/spacer.gif\" width=\"10\"></td><td height=\"20\">");
LiteralControl litNeueTabellenZeileEnde = new LiteralControl("</td><td width=\"100\" height=\"20\">" + dvAlleArtikel[nUpdatePanelIndex]["ArtPrice1"].ToString() + " € </td></tr>");
((UpdatePanel)crInRepeaterItem).ContentTemplateContainer.Controls.Add(litNeueTabellenZeileBeginn);
((UpdatePanel)crInRepeaterItem).ContentTemplateContainer.Controls.Add(CheckBox1);
((UpdatePanel)crInRepeaterItem).ContentTemplateContainer.Controls.Add(litNeueTabellenZeileEnde);
}
[... some other code here...]
LiteralControl litTabelleEnde = new LiteralControl("</table>");
((UpdatePanel)crInRepeaterItem).ContentTemplateContainer.Controls.Add(litTabelleEnde);
nUpdatePanelIndex++;
}
}
}
}
This code is never reached:
protected void CheckBox1_CheckedChanged(object sender, EventArgs e)
{
int foo = 0;
}
This is the CheckBox-Code generated:
<input id="AccordionPane2_content_RepeaterAccordionPane2_ctl00_6200" type="checkbox" name="AccordionPane2_content$RepeaterAccordionPane2$ctl00$6200" onclick="javascript:setTimeout('__doPostBack(\'AccordionPane2_content$RepeaterAccordionPane2$ctl00$6200\',\'\')', 0)" />
The Event is generated, but when i click the Checkbox all Content in the UpdatePanel is gone and the CheckedChanged-EventHandler is not fired.
What am i doing wrong?
Thanks to all advice, i´m really stuck.
mk
The first time the page loads you are adding all the checkboxes to the Controls collection, and they get rendered. When you do a postback (through the CheckBox's AutoPostBack) you have a check if(!IsPostBack) that doesn't allow the checkboxes to be added to the Controls collection on the postback. Because of that, you won't see the controls and the page, and when the page lifecycle tries to call the events (which occurs AFTER Page_Load), the controls that created the events are no longer there.
You will need to refactor your Page_Load method so it does two things - 1, regardless of the value of IsPostBack bind the repeaters and create the dynamic controls. 2, if IsPostBack==false, i.e., an initial load, then set the values of the dynamic controls. you don't want to set the values of the dynamic controls when IsPostBack==true because then you will lose the values the user entered.
also, just a note:
if (crInRepeater.GetType() == typeof(RepeaterItem))
can be rewritten as:
if (crInRepeater is RepeaterItem)
when I use " AllowPaging="True" " property in gridview and upload my webSite ,when I click next page , I can't see that and I see same record that I see already . point : I bind a dataBase on gridview,and I see that in gridview.above problem when I uplaod my website,happen . what is problem that I can't see next page of gridview ?
I am having a bit of trouble completing understanding your question. I think your are basically trying to get paging to work on a gridview.
In addition to setting "AllowPaging=True", you will need to hook into your paging event like so:
void GridView_PageIndexChanging(Object sender, GridViewPageEventArgs e)
{
e.NewPageIndex = e.NewPageIndex + 1;
DataBind();
}
Check it out on MSDN
you need to set the current page index property in Page index chaged event. then call the bind method in next line. then only you able to see the next page and it will work.
example
protected void SearchGrid_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
//set the current page index for grid
searchResultsGrid.PageIndex = e.NewPageIndex;
//Bind the result sets
BindSearchResults();
}
Custom control would help to avoid writing on page level event handlers