It's been a while since I worked on WebForms so I need a refresher when working on an old site.
I have a userControl on the page that I need to programatically set the enabled state
<%# Register Src="CalandarControl.ascx" TagName="CalandarControl" TagPrefix="uc" %>
I have this at the C# code but Enabled is not available here. What am I missing?
if (c is UserControl)
{
var x = c.GetType();
if (x.Name == "calendarcontrol_ascx")
{
((UserControl)c).Enabled = true;
}
}
Thanks
You should have something on the code-front that places the control on the page, like:
<uc:CalendarControl ID="dtePrepaymentExpiresDate" FieldName="Prepayment expires date" runat="server" Enabled="false" />
Then in the code behind, you can set this custom property as follows:
dtePrepaymentExpiresDate.Enabled = true;
If you really need to do it in the loop, then you need to cast c as the CalendarControl and not UserControl because CalendarControl has the property Enabled while a normal UserControl does not.
((CalandarControl)c).Enabled = true;
you can define a panel in usercontrol witch cotaines all of controls of the user control, then define a property Enabled named as bool (panelMain.Enabled;) and from ur page set it,
in user control ascx
<asp:panel runat="server" id="panelMain" Enabled="false">
<!-- define ur other controls between panel-->
</asp:panel>
in usercontrol ascx.cs
public bool Enabled
{
get { return panelMain.Enabled; }
set { panelMain.Enabled = value; }
}
in page first register ur usercontrol and then set Enabled property from code behind ....
for example
protected void Page_load(object sender,EventArgs e )
{
panelMain.Enabled = true;
}
as simple as drink water :))
Related
I have a ASP.NET page called customer.aspx which has a user control customerdetails.ascx inside of it. This user control reads data from the database and populate some fields. If the loading is successful (if there is some data), the user should stay on the page. Otherwise the page should be redirected to a different page. This redirection is done in the container customer.aspx page and not in the control.
What are the ASP.NET page cycle events (Page_Load Vs Page_Init) that I should use for customer.aspx and customerdetails.ascx for the above logic to work?
If you've established that both options work functionally, then, for performance, you should prefer Page_Init.
If you might end up with a redirect, then you want to give the server the chance to do that redirect as soon as possible in the page lifecycle, to avoid using resources on lifecycle steps that might not be necessary.
I was rereading this - https://web.archive.org/web/20210330142645/http://www.4guysfromrolla.com/articles/092904-1.aspx, old, but good. I think you should be able to do what you need from the Page_Load event of customer.aspx because user controls are loaded by then. simply check the user control's controls for values and redirect, or not.
edit:
Actually, I think it depends. controls prob have to be preloaded, which changes things.
If we need our dynamically added controls to maintain their view state it is paramount that these controls be added before the Load View State stage. That is, these controls must exist within the page's control hierarchy before the view state is loaded. There's only one stage before Load View State - Initialization. That means, if we want our dynamic controls to persist view state we must add them to the control hierarchy in the page's Init event.
One way to make the user control accessible (answer at bottom): https://forums.asp.net/t/1674095.aspx?Loop+through+User+Controls+in+Content+Page
edit:
User Control
<h4>The User Control</h4>
<div>
<asp:Label ID="lblUserCtrl" runat="server" Text="Label"></asp:Label>
</div>
.cs
public partial class Testing_Controls_TestCtrl : System.Web.UI.UserControl
{
// public properties
public Label lbl
{
get { return lblUserCtrl; }
set { lblUserCtrl = value; }
}
public bool isLoaded;
// end public properties.
protected void Page_Init(object sender, System.EventArgs e)
{
lblUserCtrl.Text = "User ctrl loaded at: " + DateTime.Now;
isLoaded = true;
}
protected void Page_Load(object sender, EventArgs e)
{
}
}
container page:
note: I still had to register the control even though I loaded it from code.
<%# Register Src="~/Testing/Controls/TestCtrl.ascx" TagPrefix="uc1" TagName="TestCtrl" %>
...etc...
<form id="form1" runat="server">
<h4>The Container Page</h4>
<div>
<asp:Label ID="lblContainerLabel" runat="server" Text="Label"></asp:Label>
</div>
<br />
<hr />
<asp:PlaceHolder ID="ph1" runat="server"></asp:PlaceHolder>
</form>
.cs
public partial class Testing_user_control_test : System.Web.UI.Page
{
private bool ucIsLoaded;
protected void Page_Init(object sender, System.EventArgs e)
{
Testing_Controls_TestCtrl c = (Testing_Controls_TestCtrl)Page.LoadControl("~/Testing/Controls/TestCtrl.ascx");
ph1.Controls.Add(c);
c.lbl.Text += "<br />This is text appended to the user control by the container page.";
ucIsLoaded = c.isLoaded;
}
protected void Page_Load(object sender, EventArgs e)
{
lblContainerLabel.Text = "Container page loaded at: " + DateTime.Now + "<br />The user control is loaded: " + ucIsLoaded.ToString().ToUpper();
}
}
I have the following HiddenField controls on my client pages:
<asp:HiddenField ID="hidRecordEditMode" runat="server" />
<asp:HiddenField ID="hidRecordEditId" runat="server" />
I am trying to access their value from a method located on my master page, using this code (sample):
protected string GetValue()
{
Page page = (Page)HttpContext.Current.Handler;
Control ctrlEditId;
ctrlEditId = (HiddenField)page.FindControl("hidRecordEditId");
return ctrlEditId.Value;
}
I'm being told the Value property doesn't exist. I've tried with and without casting (HiddenField), and setting the method static, to no avail.
How can I get this to work?
protected string GetValue()
{
var hfEditId = (HiddenField)ContentPlaceHolder1.FindControl("hidRecordEditId");
return hfEditId != null ? hfEditId.Value : string.Empty;
}
Where ContentPlaceHolder1 is the ID of the ContentPlaceHolder displaying your content page.
I'm trying to access a hiddenfield value from my masterpage that is set in my child aspx page, but cannot access it the masterpage codebehind page_load event.
Child aspx page:
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="Server">
<telerik:RadStyleSheetManager ID="RadStyleSheetManager1" runat="server">
</telerik:RadStyleSheetManager>
<div class="center_content">
<div style="text-align: left">
<h2>
</h2>
</div>
<div style="text-align: left">
<uc1:Chart ID="Chart1" runat="server" />
</div>
</div>
<asp:HiddenField ID="hid1" runat="server" Value="Satellite Availability % Report" />
Master page:
<asp:Label runat="server" ID="Label1" Style="text-align: right; font-size: xx-large; color: #808080"></asp:Label>
Master page code behind: This is where I want to set the text value of the report from the child page.
protected void Page_Load(object sender, EventArgs e)
{
HiddenField hid1 = (HiddenField)MainContent.FindControl("MainContent_hid1");
if (hid1 != null)
{
Label1.Text = hid1.Value;
} }
<input type="hidden" name="ctl00$MainContent$hdnRptTitle" id="MainContent_hdnRptTitle" value="Satellite Availability % Report" />
There is no intellisense for the hdnRptTitle variable.
How can I get this to work? It seems simple enough, but don't know why it not working...
You can add the below code in your MasterPage:
HiddenField hid1 = (HiddenField)MainContent.FindControl("hid1");
if (hid1 != null)
{
Label1.Text = hid1.Value;
}
EDIT: Make sure your Label on the MasterPage is outside your ContentPlaceHolder, as I made this mistake when I first tested.
The above code should work as provided, with your control names, I'm not sure why you are using:
.FindControl("MainContent_hid1");
instead of
.FindControl("hid1");
You can use like this.
There can be multiple conterntPlaceHolder on your master page.
use the id which contains your hidden field in this case I assume that it is ContentPlaceHolder1
HiddenField hid1 = (HiddenField)ContentPlaceHolder1.FindControl("hdnRptTitle");
if (hid1 != null)
{
Label1.Text = hid1.Value;
}
There is a similar post on so
How to access content page controls from master page in asp.net
You can reference a master page and get the control like this:
VB.Net:
Dim te As HiddenField
Dim val As String
te = Me.Page.Master.FindControl("hdnRptTitle")
val = te.Value
c#:
HiddenField te = default(HiddenField);
string val = null;
te = this.Page.Master.FindControl("hdnRptTitle");
val = te.Value;
Why do you think that you can access a control in a content-page of a master-page? A MasterPage is used for multiple pages, why do you want to hardlink it with a specific page, it won't work anymore without it. If the HiddenField is essential for the operation of the master you should declare it there.
For every child page, there is a different rpt title which needs to
show up on the master page. How can I accomplish this?
Then the content page can access it's master to set the text but not vice-versa.
You could provide a public property in the master, e.g.:
public string ReportTitle
{
get { return this.LblReportTitle.Text; }
set { this.LblReportTitle.Text = value; }
}
and in the ContentPage, for example in it's Page_Load:
protected void Page_Load(object sender, EventArgs e)
{
// assuming the type of your master is SiteMaster
var master = this.Master as SiteMaster;
if (master != null)
master.ReportTitle = hdnRptTitle.Value;
}
This approach is still linking the master with one (or multiple) of it's childs, but it would still "work" if the content-page would use a different master-type. You'd also be informed with a compiler error if somebody remove or change the property.
However, where the content stores the report-type or where the master displays it is an implementation detail and can be changed in future without breaking anything.
This is my ascx Code:
<%# Control Language="C#" AutoEventWireup="true" CodeFile="Demo.ascx.cs"
Inherits="Demo" %>
<asp:HiddenField ID="hidden" runat="server" Value="" />
And the aspx:
<%# Register TagName="Hidden" TagPrefix="CRS" Src="~/Demo.ascx" %>
<div>
<CRS:Hidden ID="hid" runat="server" />
</div>
Now How to access Hidden variable ID From ascx page to this cs page backend
Do you mean the actual ID? or the Value within the hidden field?
You can access the value using the FindControl method
HiddenField hf = (HiddenField)this.hid.FindControl("hidden");
string theValue = hf.Value;
Not sure if this is exactly what you are looking for.
Alternatively, you can declare some public properties in the UserControl in which you can access directly
In the ascx code:
public string theValue { get; set; }
In the aspx code:
string theValue = this.hid.theValue;
To access the HiddenField inside the UserControl from the asp.net web page you will need to wire up something called a Public Property.
This code should be added to the UserControl ascx.cs code behind:
public string Value
{
get { return hidden.Value; }
set { hidden.Value = value; }
}
You could then write code like this in your asp.net page:
string SomeHiddenValue = hid.Value;
hid.Value = "Its a secret!";
Note: I haven't compiled this so I am not sure if the public property name of Value will compile. I am also not sure if the second value in set { hidden.Value = value; } needs capitalising. Try changing these two values if you encounter problems.
I am loading a control to a page dynamically with LoadControl("src to file").
In the usercontrol i have a validator and some other controls that i would like to access from my page. I canät get it to work, null pointer exception.
Scenario is like this. I have a Edit.aspx page which loads the EditTemplate.ascx usercontroll. I would like to get information or find the controls in the EditTemplate from the Edit.aspx site.
I have tried exposing the controls and validators as properties but how do i access them from my Edit.aspx?
Example code:
Edit.aspx, the control is later added into a
Control control = LoadControl("src to ascx");
TemplatePlaceHolder.Controls.Add(control);
EditTemplate.ascx
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="CompanyImageFile" ErrorMessage="RequiredFieldValidator"></asp:RequiredFieldValidator>
CodeBehind
public partial class EditTemplate : System.Web.UI.UserControl, IEditTemplate {
public RequiredFieldValidator Validator {
get { return this.RequiredFieldValidator1; }
set { this.RequiredFieldValidator1 = value; }
}
From the Edit.aspx site i would like to check the validators isValid property. Isvalid is set in a Save method.
The save button that saves the template is located in edit.aspx, so the post in done from that page.
So the question is how to get a hold of the property from the usercontrol in the edit.aspx page, where and how should this be done?
Thanks again.
Easiest way is to have the user control define properties like:
public IValidator SomeValidator {
get { return this.cuvValidator; }
set { this.cuvValidator = value; }
}
public string Text {
get { return this.txtText.Text; }
set { this.txtText.Text = value; }
}
Which your edit page can use.
HTH.
You can always use recursive approach. Check the solution on Steve Smith's blog:
Recursive-FindControl.
As mentioned in previous answers, I would expose any validators you must access from the parent ASPX page as properties in the user control.
public RequiredFieldValidator ValidatorToCheck
{
get { return this.rfvMyField; }
}
Then, you can dynamically add your user control to some placeholder (being sure to assign an ID to the user control).
// In my example, this is occurring in the Page_Load event
Control control = LoadControl("~/Controls/EditTemplate.ascx");
control.ID = "ucEditTemplate";
pnlControlHolder.Controls.Add(control); // the placeholder in my example is a panel
When you want to access the IsValid property on the given validator (presumably in your save action) you can do so as follows (being sure to cast the control to the appropriate type and using the ID you originally assigned to the user control):
EditTemplate control = (EditTemplate)pnlControlHolder.FindControl("ucEditTemplate");
if (control.ValidatorToCheck.IsValid)
{
// Some action
}