ASP.NET - Cross Page Posting From Custom Control - asp.net

Can I get some help posting across different pages from a custom control?
I've created a custom button that raises it's own click event through the following code:
Private Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Const EventName As String = "button_click"
Const ArgName As String = "__EVENTARGUMENT"
If Page.IsPostBack _
AndAlso Request.Params IsNot Nothing _
AndAlso Request.Params(ArgName).Trim = EventName Then
Me.OnClick(Me.this_button, New EventArgs)
Else
Me.this_button.Attributes.Add("OnClick", Page.ClientScript.GetPostBackEventReference(Me.this_button, EventName))
End If
End Sub
How would I go about modifying this to let me post to a different page?
I'd like it to act as close as possible to the System.Web.UI.WebControls.Button property PostBackUrl.

You can use Cross Page Postbacks.
You can also use the WebForm_DoPostBackWithOptions js method to postback the current page to another page.

Related

how to redirect to another page, that generates a gridview, after clicking a button in the first page

i have some different buttons in a page after clicking them i want them to redirect me to a page that has a gridview , but for each button it gives a different gridview which are generated by datatables . may you help to find ,how can i do that in asp.net, vb ??
i did two pages at the gridview page i made methods that are binding different gridviews for each button , and in the first page where i have the button click events i did the redirecting to this gridview page and called the corresponding methods. it redirects me but doen't give me any gridview at all :(
Call in button action
Response.Redirect("Your Page Name.aspx")
and call in that page a BindGrid Function that you create to bind the gridview
You can redirect by using
Response.Redirect("GridView.aspx")
At the same time you can use only one aspx by using session
Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Session.Add("CheckButton", Button1Clicked)
Response.Redirect("GridView.aspx")
End Sub
Protected Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
Session.Add("CheckButton", Button2Clicked)
Response.Redirect("GridView.aspx")
End Sub
After that at your GridView.aspx on your pageload
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim CheckButton As String = Session("CheckButton")
Dim query As String
If (CheckButton = "Button1Clicked") Then
query = "SELECT * FROM Table1"
Else If (CheckButton = "Button2Clicked") Then
query = "SELECT * FROM Table2"
Else
Response.Write("<script>alert('Error!')</script>")
End If
SqlDataSource1.SelectCommand = query
SqlDataSource1.DataBind()
End Sub

CommandArgument on SQLDatasource Inserted?

I'm wishing to redirect to two different pages depending on which button is pressed on my form.
Both buttons call the Insert method of the Datasource, but only one of them needs to get hold of the newly inserted GUID and redirect using that GUID.
I'm doing it using this code
Protected Sub DSCustomers_Inserted(sender As Object, e As SqlDataSourceStatusEventArgs) Handles DSCustomers.Inserted
Response.Redirect("~/addTicket.aspx?step=2&customerID=" & e.Command.Parameters("#customerID").Value.ToString)
End Sub
But how can I know if it's the other button that has been pressed and doesn't need to redirect?
I can't get access to the CommandArgument otherwise I would just check which button has been pressed using that and then redirect accordingly.
Thanks
You can't just use a global private boolean?
Dim RedirectButtonPressed As Boolean = false
Protected Sub RedirectButton_Click(sender As Object, e As EventArgs) Handles RedirectButton.Clicked
// code code code
RedirectButtonPressed = True
End Sub
Protected Sub DSCustomers_Inserted(sender As Object, e As SqlDataSourceStatusEventArgs) Handles DSCustomers.Inserted
If RedirectButtonPressed Then
Response.Redirect("~/addTicket.aspx?step=2&customerID=" & e.Command.Parameters("#customerID").Value.ToString)
RedirectButtonPressed = False
End If
End Sub

Failure to update textbox.text

I have a relatively simple ASP.NET problem (I should think) that regrettably I am unable to solve by myself. What I am trying to do is the following:
On a page I load a number of controls (Text Boxes) programmatically;
following this load the user should be able to select a value to load into the Textbox from a panel control that is added to the page following the click of a button
Once the panel is closed, the selected text from the panel should be loaded into the textbox
However, in the vb.net statements below when run the "test" string never makes it to the textbox - any help with resolving this would be greatly appreciated.
Public Class test
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Controls_Load()
End Sub
Public Sub Controls_Load()
Dim ttf_tb As New TextBox With {.ID = "ttf_tb"}
Master_Panel.Controls.Add(ttf_tb)
Dim ttf_button As New Button
Master_Panel.Controls.Add(ttf_button)
AddHandler ttf_button.Click, AddressOf TTF_BUTTON_CLICK
End Sub
Public Sub TTF_BUTTON_CLICK(sender As Object, e As EventArgs)
Dim str As String = sender.id
Dim panel As New Panel
panel.ID = "TTF_Panel"
panel.Width = 300
panel.Height = 300
Master_Panel.Controls.Add(panel)
panel.BackColor = Drawing.Color.Black
panel.Style.Add(HtmlTextWriterStyle.Position, "absolute")
panel.Style.Add(HtmlTextWriterStyle.Left, "200px")
panel.Style.Add(HtmlTextWriterStyle.Top, "100px")
panel.Style.Add(HtmlTextWriterStyle.ZIndex, "100")
Dim CL_Button As New Button
CL_Button.ID = "TTF_Close_" & Replace(str, "TTF_Button_", "")
panel.Controls.Add(CL_Button)
AddHandler CL_Button.Click, AddressOf TTF_Close_Button_Click
End Sub
Public Sub TTF_Close_Button_Click(sender As Object, e As EventArgs)
Dim ttf_tb As TextBox = Master_Panel.FindControl("ttf_tb")
ttf_tb.Text = "Test"
Dim panel As Panel = FindControl("TTF_Panel")
Master_Panel.Controls.Remove(panel)
End Sub
End Class
I think you need to re-create your controls in the Page_Init method. It's been a while since I've done web forms but I think it's something like:
When a user clicks the button a post back is fired. This re-creates a new instance of your class, creates the controls on the page, assigns any form values then calls your Page_Load event.
The problem is you are creating your controls too late, so the forms values are never assigned correctly.
You should create / recreate your dynamic controls in the Init event:
Protected Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
Controls_Load()
End Sub
This should allow you to maintain their state across PostBacks.
For more information about this topic, see the MSDN article on the ASP.NET Page Life Cycle.

Items.Count returning 0 for a list box

I am trying to use the code below to store the items from the list into a session. For some reason when I debug the code the count is returning 0 even though there are multiple items in the list box? Any ideas what I am doing wrong here?
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
NameTextBox_AutoCompleteExtender.OnClientItemSelected = "getSelected"
End Sub
Protected Sub cmdNext_Click(sender As Object, e As System.Web.UI.ImageClickEventArgs) Handles cmdNext.Click
Dim n As Integer = NPListbox.Items.Count
Dim arr As String() = New String(n - 1) {}
For i As Integer = 0 To arr.Length - 1
arr(i) = NPListbox.Items(i).ToString()
Next
Session("arr") = arr
Response.Redirect("~/frmDescription.aspx")
End Sub
<script language="javascript" type="text/javascript">
function getSelected(source, eventArgs) {
var s = $get("<%=NameTextBox.ClientID %>").value;
var opt = document.createElement("option");
opt.text = s.substring(s.length - 10);
opt.value = s.substring(s.length - 10);
document.getElementById('<%= NPListbox.ClientID %>').options.add(opt);
}
I am going to guess that you do not have any logic in your Page_Load to populate the listbox, based upon what it had when you finished the autocomplete extender logic. Since, you do not, then when the click event fires after the Page_Load your values are gone.
Put the logic that executes on selection of the autocomplete extender in a method and have your Page_Load call that, like this:
Protected Sub Page_Load(sender As Object, e As EventArgs)
' Put call here to populate the listbox results from autocomplete extender selection
PopulateListBox()
End Sub
Private Sub PopulateListBox()
' Go to whatever resource you are using to get the values for the list box
End Sub
UPDATE:
Since you are depending upon using a client-side function to grab the values from the autocomplete extender and populating the listbox that way, you need to mimic that logic in your Page_Load on the server-side, because it will be too late if you try to use the client-side one, since you need the data server-side and all of the server-side events happen before the client-side logic in a server post back.
You need to do something like this:
Protected Sub Page_Load(sender As Object, e As EventArgs)
' Only do this when page has posted back to the server, not the first load of the page
If IsPostBack Then
' Put call here to populate the listbox results from autocomplete extender selection
PopulateListBox()
End If
End Sub
Private Sub PopulateListBox()
' Get value from text box
Dim textBoxValue As String = Me.NameTextBox.Text
' Create new item to add to list box
Dim newItem As New ListItem(textBoxValue)
' Add item to list box and set selected index
NPListbox.Items.Add(newItem)
NPListbox.SelectedIndex = NPListbox.Items.Count - 1
End Sub

Web Controls Not Talking to Each other in ASP.NET using VB.NET

I have an asp.net page that loads two controls, Control A and Control B. Control A has some generic form submit and clear buttons that trigger click events in its' own code behind which use reflection to call the update function in Control B which has a few input fields. I have debugged this and everything seems to be in order, however; when the update function in control B is called the input fields are not returning a value when using inputname.text or me.inputname.text. Does anyone have any ideas why this is not working? Any guidance would be appreciated.
This is the code in Control A's codebehind which calls the update method in Control B's code behind
Protected Sub btnSave_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnSave.Click
Try
Dim lctlControl = Session("SelectedQstnCtl")
Dim methodObj = lctlControl.GetType().GetMethod("UpdateGenInfo", BindingFlags.NonPublic Or BindingFlags.Instance)
' Execute UpdateGenInfo method to update the data
methodObj.Invoke(lctlControl, Nothing)
Catch ex As Exception
'TODO: check for concurrency error here
End Try
End Sub
This is the update function in Control B that is being called. The session values are being passed, but the form fields are not.
Protected Sub UpdateGenInfo()
Dim lclUtil As New clUtility
Dim genInfo As New clGenInfo
Try
Dim dt As Integer
'Update Data for 1-2
dt = genInfo.UpdateGenInfo_E1_01_02(Session("ConnStrEP"), Me.varLastUpdate, Session("AppNo"), Session("RevNo"), _
Me.txtPrName.Text, Me.txtPrAddr1.Text, Me.txtPrAddr2.Text, _
Me.txtPrCity.Text, Me.txtPrState.Text, Me.txtPrZip.Text)
Catch ex As Exception
'Display error
lclUtil.DisplayMsg(Me.lblErrMsg, String.Format("Error Location: Sub LoadGenInfo (ctlE1_01_02) {0}", ex.Message))
End Try
End Sub
The most likely cause is that the control instance stored in the session is not the control instance on the current page. For example, if you're storing the control instance in the session when the page is first loaded, and retrieving it on post-back, it will be a different instance.
If you can't give Control A a direct reference to Control B, then change your code to store the reference in the Page.Items collection:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
Page.Items("SelectedQstnCtl") = TheSelectedQstnCtl
End Sub
Protected Sub btnSave_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnSave.Click
Dim lctlControl = DirectCast(Page.Items("SelectedQstnCtl"), YourControlClass)
lctlControl.UpdateGenInfo()
End Sub
I see you are using reflection which might be an overkill for that task.Try referencing the method in the control directly.Make then method UpdateGenInfo public and then reference it like this.
Protected Sub btnSave_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnSave.Click
Try
Dim lctlControl = CType(Session("SelectedQstnCtl"),YourControlClass)
lctlControl.UpdateGenInfo()
Catch ex As Exception
End Sub
Public Function UpdateGenInfo()
'your code here
Catch ex As Exception
End Try
End Function
This way you can easily trace where your values are getting lost.Let me know how it goes.
Try yet another simple approach working demo here
In control a
Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim testb1 = CType(Me.NamingContainer.FindControl("testb1"), testb)
testb1.UpdateGenInfo()
End Sub
In control b
Public Function UpdateGenInfo()
Try
Dim a = Me.TextBox1.Text
Catch ex As Exception
End Try
End Function
Aspx Parent Page
<uc1:testa ID="testa1" runat="server" />
<uc2:testb ID="testb1" runat="server" />
The controls in testb are in an update panel.Try this and let me know if this works.

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