Hi,
I have a grid control containing checkbox in each group header .I want that whenever i click on Button (located on page not inside the grid) i can get all selected checkboxes in the groupheader of datagrid and also i want to get the value of any column located in selected group .
Zachary, from my experience with the RadGrid control I think that utilizing the GetItems(ItemType) method to reference all group headers and the GetChildItems() method to get access to the data items under a given group will do the trick for you. Additionally, to extract the text from the column cells for a certain item, use the unique name of the column of interest.