How to use CrossPagePostBack in Asp.net 2.0

Question

Explain me the use of CrossPagePostBack in Asap.net 2.0 with example (C# code)

Rajendra Deopura · Answer

Dear In Default mode all the Webforms post to themselves. However sometimes you need to post your form to some other Webforms. This is called as CrossPagePostBack. Example Open a New Website with a Default form 'Default.aspx'. Add a Label control a DropDownList control and a Button Control to the Default.aspx form. Set the text property of Label to Select an Id Bind the dropdownList box to Authors id. I am using BIBLIO.MDB database file. Set the Text property to 'Search' . Add another webform to the web site named Authors.aspx. Set the PostBackUrl property of Button control of Default.aspx to Authors.aspx page. Go to the view code of Default.aspx page and write the follwing code : Protected Sub Page_Load(ByVal sender As Object ByVal e As System.EventArgs) Handles Me.Load If Not Page.IsPostBack Then BindDropDownList() End If End Sub Sub BindDropDownList() Dim constr As String = Provider=Microsoft.Jet.OLEDB.4.0; Data Source=C:\Documents and Settings\USER\Desktop\BIBLIO.mdb Dim cmdstr As String = select AU_ID from Authors Dim da As New OleDbDataAdapter(cmdstr constr) Dim ds As New DataSet da.Fill(ds auth) Dim dt As DataTable = ds.Tables(auth) DropDownList1.DataSource = dt DropDownList1.DataTextField = AU_ID DropDownList1.DataValueField = AU_ID DropDownList1.DataBind() End Sub On Authors.aspx Page Drop down a GridView control. Go to the view code and write the following code : Protected Sub Page_Load(ByVal sender As Object ByVal e As System.EventArgs) Handles Me.Load If Not Page.IsPostBack Then Dim ddl As DropDownList = CType(PreviousPage.FindControl(DropDownList1) DropDownList) Dim id As Integer = Integer.Parse(ddl.SelectedValue) BindGrid(id) End If End Sub Sub BindGrid(ByVal id As Integer) Dim constr As String = Provider=Microsoft.Jet.OLEDB.4.0; Data Source=C:\Documents and Settings\USER\Desktop\BIBLIO.mdb Dim cmdstr As String = select AU_IDAuthor from Authors WHERe AU_ID= @Id Dim con As New OleDbConnection(constr) Dim com As New OleDbCommand(cmdstr con) con.Open() com.Parameters.AddWithValue(@id id) Dim r As OleDbDataReader = com.ExecuteReader GridView1.DataSource = r GridView1.DataBind() r.Close() con.Close() End Sub I have created this code in VB.Net. If you need the project mail me at r_deopura@rediffmail.com. Happy Coding!