GridView

• GridView provides a tabular grid-like view of the contents of a data source
  
• The GridView is designed to leverage the new data source object model, and it works best when bound to a data source control via the DataSourceID property
  
• A Grid can have delcared and auto generated columns at the same time
  
• Auto-generated columns are not added to the Columns collection
  
• The GridView doesn't support the AllowCustomPaging property found in DataGrid
  
• Compared to the DataGrid control, the GridView provides an extended eventing model; pre/post pairs of events, with cancelling and more
  
• It is declared as:
  

  public class Gridview : CompositeDataBoundControl, IcallbackContainer, ICallbackEventHandler
  

Properties of GridView Control

AllowPaging, AllowSorting	Support for Paging, Sorting
AutoGenerateColumns	Default is true
AutoGeneratexxxButton	Delete, Edit and Select buttons can be displayed with each reord
DataMember	Specifies which table to be bind from the DataSource
DataSource/DataSourceID	Indicates the bound data source control
EnableSortingAnd PagingCallbacks
SortDirection
SortExpression
UseAccessibleHeader

• GridView has some Style properties like AlternatingRowStyle, EditRowStyle, HeaderStyle, FooterStyle, PagerStyle, RowStyle, SelectedRowStyle
  
• GridView appearence properties include BackImageUrl, Caption, GridLines, PagerSettings, ShowFooter
  
• Templating properties are EmptyDataTemplate and PagerTemplate
  
• State Properties include: DataKeyNames, DataKeys, PageCount, SelectedIndex, SelectedRow, SelectedValue
  

Events Fired by the GridView Control

PageIndexChanging, PageIndexChanged	RowDeleting, RowDeleted
RowCancellingEdit	RowEditing
RowCommand	RowUpdating, RowUpdated
RowCreated	SelectedIndexChanging SelectedIndexChanged
RowDataBound	Sorting, Sorted

 

Configuring Columns

• Columns can Programatically be defined as:
  

  
   

  BoundField field = new BoundField();
  

  Field.DataField = "companyname";
  

  Field.HeaderText = "Company Name";
  

  grid.ColumnFields.Add(field);
  

 

• Columns can be Declaratively defines as:
  

  
   

  <columns>
  

  <asp:boundfield datafield="customerid" headertext="ID"/>
  

  </columns>
  

Column Types in GridView

• GridView supports following types of columns
  
  • BoundField
    
  • ButtonField, CheckBoxField
    
  • CommandField
    
  • HyperLinkField, ImageField, TemplateField
    

Templated Fields

• A TemplateField column gives each row in the grid a personalized UI that is completely defined by the page developer
  
• Templates can be defined for various rendering stages, including the default view, in-place editing, header etc
  
• Declared as:
  

  <asp:templateField headertext ="Product" >
  

  <itemTemplate>
  

  <b><%# Eval("productname")%></b> <br/>
  

  available in <%# Eval("quantityperunit")%>
  

  </itemtemplate>
  

  </asp:templateField>
  

 

Sorting Data

• The GridView doesn't implement a sorting algorithm; instead, it relies on the data source control (or the page, if bound to an enumerable object) to provide sorted data
  
• To enable the GridView's sorting capabilities, set AllowSorting property to true
  

Executing an Operation on a Given Row

• A RowCommand event handler is required to handle row operations
  
• GridView stores the index of the clicked row in the CommandArgument property of the GridViewCommandEventArgs structure