ok, I'm working on a custom control that can contain some javascript, and read this out of the page into a string field.
This is a workaround for dynamic javascript inside an updatepanel.
At the moment, I've got it working, but if I try to put a server tag inside the block:
<custom:control ID="Custom" runat="server">
<%= ControlName.ClientID %>
</custom:control>
The compiler does not like it. I know these are generated at runtime, and so might not be compatible with what I'm doing, but does anyone have any idea how I can get that working?
EDIT
Error message is: Code blocks are not supported in this context
EDIT 2
The control:
[DataBindingHandler("System.Web.UI.Design.TextDataBindingHandler, System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"), ControlValueProperty("Text"), DefaultProperty("Text"), ParseChildren(true, "Text"), AspNetHostingPermission(SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal), AspNetHostingPermission(SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
public class CustomControl : Control, ITextControl
{
[DefaultValue(""), Bindable(true), Localizable(true)]
public string Text
{
get
{
return (string)(ViewState["Text"] ?? string.Empty);
}
set
{
ViewState["Text"] = value;
}
}
}
The compiler is write, server side code blocks are only supported within the context of an ITemplate.
The "Text" property should be set like this ...
<custom:control ID="Custom" runat="server" Text="YourText">
Using ITemplate you can declare it in the codebehind as ...
public ITemplate Text
{
get;
set;
}
But then you would need to do this ...
<custom:control ID="Custom" runat="server">
<Text><%= ControlName.ClientID %></Text>
</custom:control>
Having said that, if you have a custom control why not just do this in the code behind ...
this.text = ((ITextControl)Page.FindControl(controlName)).Text;
Trouble is, it's not very dynamic.
I would favour the templated option.
Harder to implement though.
Related
I am having a problem passing a variable to a user control.
When I pass a hard-coded value, my control works fine. However passing a variable is not working.
My ASPX code:
<% System.Console.Out.WriteLine("Operate Flag is set to: " + operateFlag); %>
<uc:menu ID="navigationMenu" runat="server" operate="<%# operateFlag %>" />
From debug output, it is clear that operateFlag is set to 'true'.
My control codebehind only has synthesized methods as below:
public partial class MenuControl : System.Web.UI.UserControl
{
public bool operate { get; set; }
}
I also print out the received value from inside the control:
<% System.Console.Out.WriteLine("Operate Flag is received as: \'" + operate + "\'"); %>
Here, operate is received by the control as False.
I figured out a way to get my page working. Still do not understand what was wrong with the original "form."
Now, as before from OnLoad(), I set the property of the control instead of passing a variable as:
navigationMenu.operate = false;
It solves my need.
What I would like to do, is be able to pass two attributes to a user control, a ListName and a Permission, like so:
<uc:check id="uc" List="Shared Documents" Permission="OpenItems" runat="server">
<!-- have some HTML content here that is rendered if the permission is true -->
</uc:check>
Then in the actual check user control, have something similar to:
<%# Control language="C#" ClassName="check" %>
<%
// determine permission magic placeholder
if (DoesUserHavePermissions(perm))
{
// render nested HTML content
}
else
{
// abort rendering as to not show nested HTML content
}
%>
I have read the page on creating a templated control on MSDN, and while that would work - it really seems to be a bit overkill for what I am trying to do. Is there a control that already renders content based on a boolean expression or a simpler template example?
http://msdn.microsoft.com/en-us/library/36574bf6.aspx
Update:
The following code can be used in the ascx to model a very simple version of this:
<%# Control Language="C#" ClassName="PermissionCheck" %>
<%# Import Namespace="System.ComponentModel" %>
<script runat="server">
void Page_Init()
{
if (Allowed != null)
{
Panel container = new Panel();
Allowed.InstantiateIn(container);
PermissionBasedMessage.Controls.Add(container);
}
}
[PersistenceMode(PersistenceMode.InnerProperty)]
public ITemplate Allowed { get; set; }
</script>
<asp:Placeholder runat="server" ID="PermissionBasedMessage" />
Note: I oversimplified the check in the Page_Init method for this sample code. Additional logic checks can be added as needed.
And reference it in the calling HTML page:
<%# Register src="PermissionCheck.ascx" tagname="PermissionCheck" tagprefix="uc1" %>
<uc1:PermissionCheck ID="PermissionCheck1" runat="server">
<Allowed>Allowed Access</Allowed>
</uc1:PermissionCheck>
You could create a custom control instead of a user control: derive from the asp.net panel, add your two properties, then only render the control if the user has the required permission. E.g. something like this:
The control (put this in App_Code for example):
namespace MyControls
{
public class MyPanel : Panel
{
public string Permission { get; set; }
public string List { get; set; }
protected override void Render(System.Web.UI.HtmlTextWriter writer)
{
if (UserHasPermission()) base.Render(writer);
}
}
}
Using the control:
<%# Page ... %>
<%# Register Namespace="MyControls" TagPrefix="mc" %>
<html>
...
<mc:MyPanel runat="server" List="Shared Documents" Permission="OpenItems">
put content and/or other controls here
</mc:MyPanel>
...
Why don't you extend the LiteralControl, add properties for your settings, then render html to the .Value of the LieralControl? Seems pretty simple and a lot less of a headache than using Templated controls
The other answers are good for the generic form of your question, but for checking permissions SPSecurityTrimmedControl might do what you need.
Wrap your content with a place holder control and set the control's visibility to true or false (controls that have .Visible = false won't render any html)
<asp:PlaceHolder id="phWrapper" runat="server">
...
</asp:PlaceHolder>
Then in your code-behind set phWrapper.Visible = DoesUserHavePermissions(perm);
Hope that helps!
I want to build a user control suppose MyDiv.ascx.
This control renders the div tag and do few more code behind stuff like adding few attributes etc which is not a matter of concern here.
The problem is I want text between the opening and closing tags of the user control. Eg:
The text goes here with some other HTML tags.
So when do something like this I get a parsing error while running the website.
Also VS2008 warns me by saying "Content is not allowed between the opening and closing tags for element MyDiv".
Question 1: Can I do something like this i.e. text/markup between opening
and closing tags of a user control?
Question 2: If yes, how
The suggested solutions did not work for me. I found the following solutions:
Either make your user control inherit from Panel instead of only UserControl, or if you have more than one content like in my case, make your content fields be PlaceHolders instead of simple Controls.
The [PersistenceMode(PersistenceMode.InnerProperty)] is added to avoid XHTML validation warning.
public partial class DrawerControl : UserControl
{
[PersistenceMode(PersistenceMode.InnerProperty)]
public PlaceHolder BodyContent { get; set; }
[PersistenceMode(PersistenceMode.InnerProperty)]
public PlaceHolder GripContent { get; set; }
protected override void OnInit(EventArgs e)
{
base.OnInit(e);
phBodyContent.Controls.Add(BodyContent);
phGripContent.Controls.Add(GripContent);
}
}
phBodyContentand phGripContent being PlaceHolders.
This way I can use my control with any content in ASPX:
<local:Drawer ID="ctlDrawer" runat="server">
<BodyContent>
<!--Insert any ASP content here-->
</BodyContent>
<GripContent>
<!--Insert any ASP content here-->
</GripContent>
</local:Drawer>
I believe you just need to apply a couple of attributes to the control:
[ParseChildren(false)]
[PersistChildren(true)]
public class MyDiv : UserControl
{
...
You may then need to override AddedControl - I'm not sure.
Put it this way - that's what works for the one and only user control I've ever written :)
I also wanted to create a custom control with "innerHtml". This is what I ended up with (based partially on some of the earlier answers/comments)...
div.ascx.cs:
[ParseChildren(true, "Text")] //Store inner content in Text property
public partial class div : System.Web.UI.UserControl
{
public string Text { get; set; }
protected void Page_Load(object sender, EventArgs e)
{
litText.Text = Text; //Render it however you want
}
}
div.ascx:
<%# Control Language="C#" AutoEventWireup="true" CodeBehind="div.ascx.cs" Inherits="TestApp.Controls.div" %>
<div>
<asp:Literal ID="litText" runat="server" />
</div>
Test page:
<%# register src="~/Controls/div.ascx" tagname="div" tagprefix="uc" %>
<uc:div ID="div1" runat="server">Test data</uc:div>
I found this:
ASP.Net: User control with content area, it's clearly possible but I need some details
Works like a charm, but I wish I could suppress the design time message, content is not allowed between opening and closing tags, but it works at run time.
[ParseChildren(true, "Content")]
[PersistChildren(false)]
public partial class CollapsiblePanelControl : UserControl
{
private Control content;
// add the content
this.MainContent.Controls.Add(content);
// if this is not a post back
if (!this.IsPostBack)
{
// set to true;
this.Expanded = true;
}
}
The markup is like this:
<asp:Panel ID="CollapsiblePanelMainPanel" runat="server" CssClass="collapsiblepanel">
<asp:Panel ID="CollapsibleHeaderPanel" runat="server" CssClass="collapsibleheaderpanel">
<asp:ImageButton ID="CollapseButton" ImageUrl="~/Images/BlueArrowDown.png" runat="server" OnClick="ExpandButton_Click" CssClass="expandbutton" />
<asp:Label ID="CollapsiblePanelHeaderLabel" runat="server" Text="Collapsed" CssClass="collapsiblelabel"></asp:Label>
</asp:Panel>
<asp:Panel ID="MainContent" runat="server">
</asp:Panel>
</asp:Panel>
And then in the client:
<dc:CollapsiblePanelControl ID="CheckOnMePanel" runat="server" CssClass="checkonmepanel" EnableViewState="true"
CollapsedHeight="20px" ExpandedHeight="300px" Expanded="true" HeaderText="Check On Me Email Service" >
<Content>
...[Your Content Goes Here]
</Content>
</dc:CollapsiblePanelControl>
Add a Text property to your control and linked this text property to a label run at server that will be between the opening and closing div.
You might want to be careful, what if you put a server control in the content area...
You might just want to make a control inherit from a panel and override any methods you need to adjust? Might be easier or harder depending on what you need to customize
public class MyDiv : Panel
{
}
My User Control has the following properties:
private String _requestIP;
public String RequestIP
{
get { return _requestIP; }
set { _requestIP = value; }
}
When adding a instance of the Control to an aspx page at design time it's easy to assign the attributes which can be utilized in the codebehind file...
<uc:Item ID="Testing" runat="server" RequestIP="127.0.0.1" />
However, if I try to create the control at runtime in the aspx.cs file, how am I able to assign values to these attributes?
Control ItemX = (Control)Page.LoadControl("/controls/item.ascx");
There is no ItemX.Attributes.Add() method which I would expect to be there, and no ItemX.RequestIP property to set.
Is there a way to set this dynamically in the aspx page using <%= Users_IP_Address %> tags or some other method?
Well, you just need to cast it to the appropriate type (whatever the class name of your user control is).
I have a custom control which includes a property of the following definition:
[PersistenceMode(PersistenceMode.InnerProperty)]
public ITemplate Template {
get { return template; }
set { template = value; }
}
The control overrides CreateChildControls(), and adds several HtmlGenericControls and an asp:Panel control.
The actual actual implementation of the control looks something like this:
<user:Frame runat="server">
<Template>
<asp:Literal runat="server" ID="SomeControl" Text="SomeValue" />
</Template>
</user:Frame>
While the page renders as intended, it has a number of consequences of varying severity, including:
Controls enclosed within the Template cannot be referenced directly, and FindControl is required. This is fine.
I've been unable to use validation controls on them.
Is there a better way to design my custom control? Or perhaps just a way to get validation working?
By default the framework assumes that you may have more than one template in a control, like say in a Repeater. In your case you have to tell it that you intend to have a single template by using the TemplateInstance property. E.g.
[PersistenceMode(PersistenceMode.InnerProperty)]
[TemplateInstance(TemplateInstance.Single)]
public ITemplate Template {
get { return template; }
set { template = value; }
}
This will allow you to reference the templated controls directly, and should fix your validation problems as well.
One way to get validation to work in this case is to add the validation controls programatically. For example:
var c = parentControl.FindControl("id");
parentControl.Controls.AddAt(
parentControl.Controls.IndexOf(c) + 1,
new RequiredFieldValidator() { ControlToValidate = c.D });