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GridView don't Show on GridView_PageIndexChanging

I have a panel ViewStock where i am viewing stock in a gridview from database and DataBind() it via code. Allowed paging and created and event "OnPageIndexChanging" in gridview tag in html, Implemented the defined code above and paging in an event as follows:
HTML:
<asp:Panel ID="Panel_StockView" runat="server">
<asp:GridView ID="GridView_Stock" AllowPaging="true" OnPageIndexChanging="GridView_PageIndexChanging" runat="server"></asp:GridView>
</asp:Panel>
Code C#:
protected void LinkButton_Panel_ViewStock_Click(object sender, EventArgs e)
{
using(SqlConnection con = new SqlConnection(cs))
{
//Sql command here
/sql adapter and filled datatable
sdaStockView.Fill(dtStockView);
GridView_Stock.DataSource = dtStockView;
GridView_Stock.DataBind();
}
}
And now the Implemented Paging
protected void GridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView_Stock.DataBind();
GridView_Stock.PageIndex = e.NewPageIndex;
}
it does work but partially. It does the paging and does the data correctly. But, the issue is when i click the page '2' the panel blanks out just like in the picture i uploaded See this Image, then i click the link button that redirects me to the panel again and opens the page '2' of the gridview with valid data.
How to resolve this issue?

Extract the logic which binds the GridView to data into a new method.You can call it BindData() for example:
private void BindData()
{
using (SqlConnection con = new SqlConnection(cs))
{
sdastockview.fill(dtstockview);
gridview_stock.datasource = dtstockview;
gridview_stock.databind();
}
}
Call this method inside LinkButton_Panel_ViewStock_Click to populate the GridView:
protected void LinkButton_Panel_ViewStock_Click(object sender, EventArgs e)
{
this.BindData();
}
Lastly, call it again to re-populate the GridView during paging:
protected void GridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView_Stock.PageIndex = e.NewPageIndex;
this.BindData();
}
Just make those three little changes and it will work. I've tried this on my side and it's working just fine.

Save your DataSet somewhere like ViewState on LinkButton_Panel_ViewStock_Click after filling DataSet like this
ViewState["ds"] = dtStockView
In PageIndexChanging write like this
protected void GridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
panel_ViewStock.visible = true;
GridView_Stock.PageIndex = e.NewPageIndex;
GridView_Stock.DataSource = ViewState["ds"] as DataSet
GridView_Stock.DataBind();
}
Hope this will help you

You can try to use:
protected void GridView_RowCommand(object sender, GridViewCommandEventArgs e)

Why is my gridview rebound after selected index change?

I have a Gridview that is populated through SQLDataSource. The query behind is rather complex and the GridView takes some seconds to get filled; that's why I get annoyed by the fact that every time I select a row, the Gridview disappears for a while and is getting repopulated again. What does fire that rebind?
The selected row index works as Control Parameter for a second Gridview, that displays detail information on that row. There are these 2 events defined for the gridview:
protected void GridView_PURCHTABLE_OnDataBound(object sender, EventArgs e) {
if(DisplayPurchItems.Checked == false)
{
GridView_PURCHTABLE.Columns[4].Visible = false;
}
else
{
GridView_PURCHTABLE.Columns[4].Visible = true;
}
protected void GridView_PURCHTABLE_Selectedindexchanged(Object sender, EventArgs e) {
GridView_Notes.DataBind(); //this is the second gridview
}
Anyone has a clue what might cause the gridview to rebind?
Martin

Check once:Is post back.
protected void Page_Load(object sender, EventArgs e)
{
if (!this.IsPostBack)
{
//binding grid
}
}

Pagination of GridView in ASP.NET (Won't go to page 2,3, etc.)

I have a Gridview and I want to set Pagination. So far I have:
<asp:GridView ID="grdActivity"
runat="server"
AutoGenerateColumns="False"
AllowPaging="True"
PageSize="30"
OnPageIndexChanging="gridView_PageIndexChanging">
C# code on the back is:
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
dsActivity myDataSet = new dsActivity();
myDataSet = clsDataLayer.GetActivity(Server.MapPath("DB.mdb"));
grdActivity.DataSource = myDataSet.Tables["tblActivity"];
grActivity.DataBind();
}
}
protected void gridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
grdActivity.PageIndex = e.NewPageIndex;
grdActivity.DataBind();
}
I get no errors but when I press any other page (2 and on), nothing shows, just a blank page and the GridView disappears. Am I missing something? I see hundreds of pages showing this exact code to do this.

You will need to re-assign your datasource property. After the postback the grActivity.DataSource is null, and calling DataBind on it will clear the grid.
protected void gridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
//re-assign your DataSource
dsActivity myDataSet = new dsActivity();
myDataSet = clsDataLayer.GetActivity(Server.MapPath("DB.mdb"));
grdActivity.DataSource = myDataSet.Tables["tblActivity"];
//Set the new page index
grdActivity.PageIndex = e.NewPageIndex;
//apply your changes
grdActivity.DataBind();
}
Some notes:
you should consider re-factoring the code that brings you the data into a single method called on Page_Load and inside the gridview_PageIndexChanging (see #ekad's answer)
if you have a lot of data you should consider paging the data directly on the database. Right now if your table has 500 rows all will be loaded into the dataset even if just a small part of it (the page size) will be displayed in the grid

Hi you please keep the code in a separate method and call it in page load event and page index changed event, something like
protected void FillGrid()
{
dsActivity myDataSet = new dsActivity();
myDataSet = clsDataLayer.GetActivity(Server.MapPath("DB.mdb"));
grdActivity.DataSource = myDataSet.Tables["tblActivity"];
grActivity.DataBind();
}
and in the page index changing event
protected void gridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
grdActivity.PageIndex = e.NewPageIndex;
FillGrid();
}
and in page load in !post back event simply call the method, like
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
FillGrid();
}
}

You have to set the data source of grdActivity before calling grdActivity.DataBind() in gridView_PageIndexChanging method. I would also suggest creating a separate method to avoid repeating the same code in Page_Load and gridView_PageIndexChanging
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
grdActivity.DataSource = GetDataSource();
grdActivity.DataBind();
}
}
private DataTable GetDataSource()
{
dsActivity myDataSet = new dsActivity();
myDataSet = clsDataLayer.GetActivity(Server.MapPath("DB.mdb"));
return myDataSet.Tables["tblActivity"];
}
protected void gridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
grdActivity.PageIndex = e.NewPageIndex;
grdActivity.DataSource = GetDataSource();
grdActivity.DataBind();
}

Gridview PageIndex not changing on page_Load event

I'm trying to change pageindex on page_Load event but its not working.
I can change page by clicking links in the page after page loaded.
If this info necessary GridView in UpdatePanel.
protected void Page_Load(object sender, EventArgs e)
{
/*...Some Codes...*/
//I'm trying to change page like this.
GridView1.PageIndex = Index;
GridViewPageEventArgs ea = new GridViewPageEventArgs(GridView1.PageIndex);
GridView1_PageIndexChanging(sender, ea);
}
protected void GridView1_PageIndexChanging(object sender,GridViewPageEventArgs e)
{
GridView1.PageIndex = e.NewPageIndex;
}

I believe that you need to rebind the data to your gridview after you change the page index.

error paging and editing in gridview

I had gridview which retrieve Products from database by sqldatasource1 ,and my manager asked me to filter this gridview by DDL to filter gridview with specfic Model ,I add some function on gridview as edit,paging .I did my code well and gridview filtred by the Model_Id which come from DDL .But when I tried to edit any product or navigate through paging I faced this error (The GridView 'GridView1' fired event PageIndexChanging which wasn't handled. )when paging ,And this for editing (The GridView 'GridView1' fired event RowEditing which wasn't handled.)
So please any one help me.
(CS)
protected void Page_Load(object sender, EventArgs e)
{
BindGridFunction();
}
private void BindGridFunction()
{
if (DDLModel.SelectedIndex < 0)
{
GridView1.DataSource = SDSModel;
GridView1.DataBind();
}
else
{
GridView1.DataSource = SDSModel2;
GridView1.DataBind();
}
}

You need to explicitly handle PageIndexChanging() and RowEditing() event through code behind.
like
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView1.PageIndex = e.NewPageIndex;
GridView1.DataBind();
}
public void GridView1_RowEditing(Object sender, GridViewEditEventArgs e)
{
//do your code here
}