How to get items count based on group in radgrid

[Dhamodharan]

Hi,

I am using radgrid grouping. i want to display the count in header based on grouping. i have attached image please check,
(ie) i want to display count same as footer count. please check the image,

i am using the code

 For Each item As GridGroupHeaderItem In rgDetailGroup.MasterTableView.GetItems(GridItemType.GroupHeader)
            Dim grpHdrText As String() = item.DataCell.Text.Split("-")
            item.DataCell.Text = (grpHdrText(0) + "-" + item.GetChildItems().Length.ToString)
        Next

This code returns count correctly if i selected one grouping. but selecting another grouping second header count looks good. but first header not shown correct count. please help for this one,

Thanks in Advance,
Dhamu.

[Andrey]

Hello Dhamodharan,

An easier way to achieve the same functionality is to use the bullt-in GroupHeader aggregates. This will help you avoid the unnecessary calculations.

I am attaching a sample project to illustrate this approach.

Kind regards,
Andrey
the Telerik team

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[Dhamodharan]

Hello Andrey,

  I want display items count in header based on grouping. please see the attached image in previous post. please let me know if you have any idea about that one,


Thanks in Advance,
Dhamu.

[Andrey]

Hello Dhamodharan,

I modified the sample project to illustrate how you can achieve the desired functionality. 
Review the following help topics for additional information:

GroupBy Expression
Declarative definition of GroupBy Expressions
Programmatic creation of GroupBy Expressions

There you could find how to customize the demonstrated approach so it fully suits your requirements.

Regards,
Andrey
the Telerik team

[Dhamodharan]

Hi Andrey,

This is what i need. looks good. thanks for your help.

Thanks,
Dhamu

[nguyen]

Hello Andrey,
 
 your sample is good , but when i am using grid with dinamic column. perhaps we should count item in code behind.

How can i  count when using code behind?
Here is my code:

   protected void grid_OnPreRender(object sender, EventArgs e)
        {
            foreach (GridGroupHeaderItem groupHeader in grid.MasterTableView.GetItems(GridItemType.GroupHeader))
            {
                GridItem[] children = groupHeader.GetChildItems();
                _count = children.Count();
                groupHeader.DataCell.Text = "Count=" + _count.ToString();
                _count = 0;
            }
        }

thank you!

[Angel Petrov]

Hi Nguyen,

I am not sure that I fully understand the requirement but I suppose that you want to obtain the total number of items for a specific group. This is achievable by subscribing to the ItemDataBound event and executing the below shown logic:

public void RadGrid1_ItemDataBound(object sender, Telerik.Web.UI.GridItemEventArgs e)
{
    if (e.Item is GridGroupHeaderItem) {
        GridGroupHeaderItem item = (GridGroupHeaderItem)e.Item;
        DataRowView groupDataRow = (DataRowView)e.Item.DataItem;
        int count=int.Parse(groupDataRow["count"]);

    }
}

You can store the counts in a dictionary for example and later in the PreRender event of the grid modify the header cells text.

Regards,
Angel Petrov
Telerik

[nguyen]

Hello angel Petrov,

i get error from your  code

count is neither a DataColumn nor a DataRelation for table GroupedTable0.

 i can find the count from where?

[Angel Petrov]

Hello Nguyen,

Please try the following:

protected void RadGrid1_ItemDataBound(object sender, GridItemEventArgs e)
   {
       if (e.Item is GridGroupHeaderItem)
       {
           GridGroupHeaderItem item = (GridGroupHeaderItem)e.Item;
           DataRowView groupDataRow = (DataRowView)e.Item.DataItem;
           int count = int.Parse(groupDataRow.Row.ItemArray[0].ToString());
       }
   }

If that does not help to extract the item count I would like to ask you to share with us the markup and code-behind of the page so we could get a better understanding of the problem.

Regards,
Angel Petrov
Telerik