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Custom Ext.Net component dynamically initialization

I am trying to create a custom component. The component should by dynamically initialized in code behind. The component presents a custom Window containing other components, like datefields, dropdown fields etc. I derived my class from Ext.Net.Window and added simple DateField. The date should than be used by a button click on the server (Date should not be passed over DirectMethod parameter). When I add this component to mark-up it works perfectly. But when I add the window in code behind, the value of the datefield is not set after the server call.
I am creating the window in the life cycle in OnInit event by "Controls.Add(mywindow)". It would be great if anybody could give me a hint. Here my window code (onExecuteButtonClick just calls the direct method and hides the window):
public sealed class WindowFilterComponent:Window
{
private const string Script = "MyProject.JavaScript.src.WindowFilterComponent.js";
public override string InstanceOf
{
get
{
return "MyProject.Filter.WindowFilterComponent";
}
}
public override string XType
{
get
{
return "windowfiltercomponent";
}
}
private Button _btnExecute;
private Button _btnCancel;
private DateField _dateField;
protected override void OnInit(EventArgs e)
{
AutoHeight = true;
_btnExecute = new Button("Execute Export");
_btnExecute.Listeners.Click.Handler = string.Format("#{{{0}}}.onExecuteButtonClick()", ID);
_btnCancel = new Button("Cancel");
_btnCancel.Listeners.Click.Handler = string.Format("#{{{0}}}.onCancelButtonClick()", ID);
Buttons.Add(_btnExecute);
Buttons.Add(_btnCancel);
_dateField = new DateField();
Items.Add(_dateField);
base.OnInit(e);
}
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
if (ExtNet.IsAjaxRequest || Page.IsCallback) return;
ResourceManager.GetInstance().AddDirectMethodControl(this);
}
[DirectMethod(ShowMask = true)]
public void ExecuteClick()
{
var date = _dateField.SelectedValue;
}
}
Now the useage in my page in the OnInit event:
protected override void OnInit(EventArgs e)
{
var myWindow = new WindowFilterComponent()
{
Hidden = false,
Width = 500
};
myWindow.ID = myWindow.ID + "MyComponent";
Controls.Add(myWindow);
base.OnInit(e);
}

I think the Window is rendered outside of the Form.
Please replace
Controls.Add(myWindow);
with
Form.Controls.Add(myWindow);
Also I would recommend to set up explicit IDs for the submittable fields (the DateField in your case) to ensure that the id key from POST data will match the control's ID on the server.

How to access user control properties from page?

I am having problem in accessing user control properties from page.
I have usercontrol on master page with some properties,but i am unable to access them from the codebehind of the page which uses that master page.i want to set some properties of usercontrol on page load.Can anyone suggest how can i access them from page.
E.G.
User Control
ucTabSystem.ascx has following properties:
public string TabName
{
get { return _tabName; }
set { _tabName = value; }
}
public string TabUrl
{
get { return _tabUrl; }
set { _tabUrl = value; }
}
Master Page
InHouseTPAMaster.master has this user control in it.
ClaimHomePage.aspx
Uses Master page InHouseTPAMaster.master and i want to set usercontrol properties in page load of this page.

You can use two methods.
The first is by using Page.Master.FindControl('controlID'). Then you can cast it to the type of your user control. The second method is by adding a <%# MasterType VirtualPath="" TypeName=""%> tag to your aspx page. In the VirtualPath add the virtual path to the master page, and the class in the TypeName. You can then access everything with intellisense

You can try this way to set your properties...
<%# Register TagPrefix="Tab" TagName="sys" Src="ucTabSystem.ascx" %>
<tab:sys id="mysys" runat="server" TabName="xxxxx" TabUrl = "yyyy" />

You need to define a public interface with two properties - TabName and TabUrl in separate code file.
public interface IUserControl
{
string TabName{get;set;}
string TabUrl {get;set;}
}
Implements the IUserControl interface to UserControl class. For instance, I've MyUserControl and its code-behind is:
public partial class MyUserControl : System.Web.UI.UserControl , IUserControl
{
public string TabName
{
get { return ViewState["TabName"] == null ? string.Empty : ViewState["TabName"].ToString(); }
set { ViewState["TabName"]= value; }
}
public string TabUrl
{
get { return ViewState["TabUrl"] == null ? string.Empty : ViewState["TabUrl"].ToString(); }
set { ViewState["TabUrl"] = value; }
}
protected void Page_Load(object sender, EventArgs e)
{
}
}
Register MyUserControl in MasterPage and it has following markup in it.(master page)
<%# Register src="MyUserControl.ascx" tagname="MyUserControl" tagprefix="uc1" %>
......
<uc1:MyUserControl ID="MyUserControl1" runat="server" />
In Page_Load event (or any other) handler of aspx page (Which is a content page of said master page).
protected void Page_Load(object sender, EventArgs e)
{
IUserControl control = Master.FindControl("MyUserControl1") as IUserControl;
control.TabName = "Something";
control.TabUrl = "http://www.example.com";
}

Accessing usercontrols in code-behind in ASP.NET

This question is for an ASP.NET guru. Its driving me nuts.
I have inherited an ASP.NET Web Forms application. This application uses a complex
structure of nested user controls. While complex, it does seem necessary in this case.
Regardless, I have a page that uses a single UserControl. We will call this UserControl
root control. This UserControl is defined as follows:
widget.ascx
<%# Control Language="C#" AutoEventWireup="true" CodeFile="widget.ascx.cs" Inherits="resources_userControls_widget" %>
<div>
<asp:Panel ID="bodyPanel" runat="server" />
</div>
widget.ascx.cs
public partial class resources_userControls_widget : System.Web.UI.UserControl
{
private string source = string.Empty;
public string Source
{
get { return source; }
set { source = value; }
}
private string parameter1 = string.Empty;
public string Parameter1
{
get { return parameter1; }
set { parameter1 = value; }
}
private DataTable records = new DataTable();
public DataTable Records
{
get { return records; }
set { records = value; }
}
protected override void OnPreRender(EventArgs e)
{
base.OnPreRender(e);
UserControl userControl = LoadControl(source) as UserControl;
if (parameter1.Length > 0)
userControl.Attributes.Add("parameter1", parameter1);
bodyPanel.Controls.Add(userControl);
}
private void InsertUserControl(string filename)
{
}
}
In my application, I am using widget.ascx in the following way:
page.aspx
<uc:Widget ID="myWidget" runat="server" Source="/userControls/widgets/info.ascx" />
page.aspx.cs
protected void Page_Load(object sender, EventArgs e)
{
DataTable table = GetData();
myWidget.Records = table;
}
Please notice how info.ascx is set as the UserControl we want to load in this case. This approach is necessary in this case. I've removed the extraneous code that justifies it to focus on the problem. Regardless, in info.ascx.cs I have the following:
info.ascx.cs
protected void Page_Load(object sender, EventArgs e)
{
// Here's the problem
// this.Parent.Parent is a widget.ascx instance.
// However, I cannot access the Widget class. I want to be able to do this
// Widget widget = (Widget)(this.Parent.Parent);
// DataTable table = widget.Records;
}
I really need to get the value of the "Records" property from the Parent user control. Unfortunately, I can't seem to access the Widget class from my code-behind. Are there some rules about UserControl visibility at compile time that I'm not aware of? How do I access the Widget class from the code-behind of info.ascx.cs?
Thank you!

Firstly you need to create an interface and implement it to the Widget user control class.
For instance,
public interface IRecord
{
DataTable Records {get;set;}
}
public partial class resources_userControls_widget : System.Web.UI.UserControl, IRecord
{
...
}
And in code behind of Info.ascx.cs,
protected void Page_Load(object sender, EventArgs e)
{
// Here's the problem
// this.Parent.Parent is a widget.ascx instance.
// However, I cannot access the Widget class. I want to be able to do this
// Widget widget = (Widget)(this.Parent.Parent);
// DataTable table = widget.Records;
IRecord record=this.Parent.Parent;
DataTable table = widget.Records;
}

In your case, maybe better to use some server object's like ViewState or Session. Fill it within DataTable on your page and get it in Page_load event handler on info.ascx user control.

How to use user control multiple times on single page(Asp.net C#)

I'm making one user control.
This user control is for to display advertisment from database.
Just we have to pass the place id and it will fetch the record from database and display on specific page.
It's working perfectly but when im draging this user control multiple time on same page then it doesn't work perfectly.
Means im passing different different place id for each usercontrol but both usercontrol takes only one place id and display same content in both usercontrol
Here is the code im using
public partial class Advertisment : System.Web.UI.UserControl
{
static int _Advertismentid;
#region Get Set Property
public int Placeid
{
get
{
return _Advertismentid;
}
set
{
_Advertismentid = value;
}
}
#endregion
#region Load Advertisment Function
public void FnLoadAdvetsiment()
{
DataTable dt = new cls_Advertisements().FnGetAdvertsimentContent(Convert.ToInt32(Placeid));
int i = 0;
DataView dv = new DataView();
if (dt.Rows.Count > Convert.ToInt32(Session["rowno"]))
{
i = Convert.ToInt32(Session["rowno"]);
ltrAdvertisment.Text = (dt.Rows[i]["Content"].ToString());
AdTimer.Interval = Convert.ToInt32(dt.Rows[i]["Timer"].ToString());
Session["rowno"] = Convert.ToInt32(Session["rowno"]) + 1;
}
else
{
Session["rowno"] = i = 0;
ltrAdvertisment.Text = dt.Rows[i]["Content"].ToString();
AdTimer.Interval = Convert.ToInt32(dt.Rows[i]["Timer"].ToString());
}
}
#endregion
#region Page Load Event
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
FnLoadAdvetsiment();
if (Session["rowno"] == null)
{
Session["rowno"] = 0;
}
}
}
#endregion
#region Timer Tick Event
protected void Timer1_Tick(object sender, EventArgs e)
{
FnLoadAdvetsiment();
}
#endregion
}

I assume your problem is that both ads are displaying the same content.
Its likely this is because you are using the same sessions variables to store the data in. Try prefixing the session key with the id of the control or something else unique or even better try to not sure session at all if you can.

When you declare a variable as "static" then only a single instance of the variable is referenced across all different instances of your control class.
Effectively, the last value you set the "_Advertismentid" variable to will be the same value for all controls.
Declare your variable as;
int _Advertismentid;

Web Controls within UserControl null?

I've built a small User Control which is essentially a DropDownList with some preset Values based on what the Target-Property is set on.
Here's the Code:
public partial class Selector : System.Web.UI.UserControl
{
public string SelectedValue { get {return this.ddl.SelectedValue; } }
public int SelectedIndex { get { return this.ddl.SelectedIndex; } }
public ListItem SelectedItem { get { return this.ddl.SelectedItem; } }
private string target;
public string Target { get { return this.target; } set { this.target = value; } }
protected void Page_Load(object sender, EventArgs e)
{
ddl.DataSource = target=="Group"?Util.GetAllGroups(Session["sessionId"].ToString()):Util.GetAllUsers(Session["sessionId"].ToString());
ddl.DataBind();
}
}
ASP-Markup:
<%# Control Language="C#" AutoEventWireup="true" CodeBehind="Selector.ascx.cs" Inherits="InspireClient.CustomControls.Selector" %>
<asp:DropDownList runat="server" ID="ddl">
</asp:DropDownList>
If I insert my Selector into an aspx-Page it works just fine.
Example:
<SCL:Selector Target="Group" runat="server" />
However, If I programmatically add it like this
ctrl = new Selector();
ctrl.Target = "User";
the DropDownList "ddl" is null and the application (logically) throws an error. Is Page_Load the wrong Method to do such a thing? What am I doing wrong?
I should add, "ctrl" is of type dynamic, not sure if this has anything to do with it.
Thanks in advance!
Dennis

Since you're dynamically adding a user control and not a "simple" web control, you should use the LoadControl() method to instantiate it:
protected void Page_Load(object sender, EventArgs e)
{
Selector yourControl = (Selector) LoadControl("Selector.ascx");
yourControl.Target = "User";
Controls.Add(yourControl);
}