Render control as ASP not HTML - asp.net

I'm in the need to take an object of WebControls type and generate the ASP.NET markup.
Dim lblTest as New Label
lblTest.ID = "lblTest"
lblTest.Text = "Text Here"
lblTest.CssClass = "myClass"
Would generate the following string.
<asp:Label id="lblTest" runat="server" CssClass="myClass" Text="Text Here" />
I'm hoping to expand this idea to numerous controls that have the flexibility to handle numerous attributes. The end result would be to take a collection of objects and to generate either a .ascx or .aspx based upon the user's input.

If you use a Placeholder, you could then add as many controls to it as you'd like.
Dim lblTest As New Label
lblTest.ID = "lblTest"
lblTest.Text = "Text Here"
lblTest.CssClass = "myClass"
PlaceHolder1.Controls.Add(lblTest)

Related

ASP.NET v2 - RadGridView

I have a grid that I need to add columns to dynamically (programatically).
I have been browsing Telerik forums as well as Google and im not able to find anything. Decompiling GridTemplateColumn shows that there should be ItemTemplate property however my VS throws an error.
Dim col As GridColumn = New GridButtonColumn()
col.UniqueName = stockLocation("LocationID").ToString()
col.HeaderText = stockLocation("Name").ToString()
col.ItemTemplate = ERROR HERE
rgGridCombinations.Columns.Add(col)
I'm trying to create a column that will look like following ASPX code.
<radg:GridTemplateColumn HeaderText="Stock" UniqueName="Stock" Visible="true" HeaderStyle-Width="10%">
<ItemTemplate>
<asp:TextBox ID="tbStock" runat="server" Width="100%" />
</ItemTemplate>
</radg:GridTemplateColumn>
How would I create this?
1) GridColumn does not have ItemTemplate property
2) You were assigning GridButtonColumn. Use GridTemplateColumn instead
Try this
Dim col = As New GridTemplateColumn()
col.UniqueName = "Stock"
col.HeaderText = "Stock"
col.ItemTemplate = <something here> 'should be an ITemplate
rgGridCombinations.Columns.Add(col)
For more information on how to create template, check here

Hide / unhide Label, textbox depending on the db results in asp.net

I need to hide /unhide the labels and textbox depending on db results , I tried something like this but it doesnt works, the condition should be like if the db field is empty for that field , then the label associated with that field should hidden (not visible) , following is the code i tried :
<asp:Label ID="lblBirth" Text="DOB:" runat="server" ViewStateMode="Disabled" CssClass="lbl" />
<asp:Label ID="DOB" runat="server" CssClass="lblResult" Visible='<%# Eval("Berth") == DBNull.Value %>'></asp:Label>
Code behind:
protected void showDetails(int makeID)
{// get all the details of the selected caravan and populate the empty fields
DataTable dt = new DataTable();
DataTableReader dtr = caravans.GetCaravanDetailsByMakeID(makeID);
while (dtr.Read())
{
//spec
string value = dtr["Price"].ToString();
lblModel.Text = dtr["model"].ToString();
birthResult.Text = dtr["Berth"].ToString(); }}
To make your aspx version work your control should be data bound to data source that contains "Berth" property. As I can see from code behind, you prefer to use c# to populate controls. In this case you may just do the following:
DOB.Visible = dtr["Berth"] == DBNull.Value;
I think that using data binding is more preferable solution.

Create labels dynamicly on ASP.NET (VB)

I want to create labels in my page dynamicly, for example the user will choose in a textbox the number of labels, and I will display the number of this label with .text = "XYZ".
Thanks.
The quick and dirty method (this example adds 10 labels and literals to a PlaceHolder on an ASP.NET page:
Dim c As Integer = 0
While c < 10
Dim lab As New Label()
Dim ltr As New Literal()
lab.Text = c.ToString()
ltr.Text = "<br/>"
PlaceHolder1.Controls.Add(lab)
PlaceHolder1.Controls.Add(ltr)
C+=1
End While
Look at using a Repeater control:
Using the ASP.NET Repeater Control
Data Repeater Controls in ASP.NET
There's a number of things that will need to be done to make this work, but to simply dynamically create controls and add them to the page, you will need a Placeholder on your ASPX page:
<asp:TextBox ID="txtLabelCount" runat="server" />
<asp:Button ID="btnCreate" runat="server" Text="Create" /><br />
<asp:Placeholder ID="PlaceHolder1" runat="server" />
Then, in btnCreate's click event handler:
' Number of labels to create. txtLabelCount should be validated to ensure only integers are passed into it
Dim labelCount As Integer = txtLabelCount.Text
For i As Integer = 0 To labelCount - 1
' Create the label control and set its text attribute
Dim Label1 As New Label
Label1.Text = "XYZ"
Dim Literal1 As New Literal
Literal1.Text = "<br />"
' Add the control to the placeholder
PlaceHolder1.Controls.Add(Label1)
PlaceHolder1.Controls.Add(Literal1)
Next

Setting LinkButton Title in ASP.Net Wizard Sidebar Template

Playing around with customizing the appearance of the Wizard control in ASP.Net, and I've found out how to disable the sidebar buttons using the SideBarTemplate and catching the OnItemDataBound event. All pretty easy. What I want to do now is to modify the text of the rendered LinkButton to prefix the step name with something like ">>" for the current step.
So, in my ItemDataBound event handler for the SideBarList, I have the following code:
Dim stepCurrent As WizardStep = e.Item.DataItem
Dim linkCurrent As LinkButton = e.Item.FindControl("SideBarButton")
If Not stepCurrent Is Nothing Then
Trace.Write("SideBar", "Current Step = " & stepCurrent.Wizard.ActiveStep.Name)
Trace.Write("Sidebar", "Link Button = " & linkCurrent.Text)
linkCurrent.Enabled = False
If stepCurrent.Wizard.ActiveStepIndex = e.Item.ItemIndex Then
linkCurrent.Style.Add(HtmlTextWriterStyle.Color, "#000000")
linkCurrent.Style.Add(HtmlTextWriterStyle.FontWeight, "bold")
linkCurrent.Text.Insert(0, ">> ")
End If
End If
However, what I find is the trace output is showing an empty string for the lunkbutton text, but the style changes work.
Am I trying to set the text in the wrong place?
Thanks
I did not find any way to change "SideBarButton" text property that is why I added
another link button control in SelectedItemTemplate to DataList and set visible="fasle" in SideBarButton. SelectedItemTemplate will be used to render item in sidebar for current wizard step.
<ItemTemplate>
<asp:LinkButton ID="SideBarButton" runat="server"/>
</ItemTemplate>
<SelectedItemTemplate>
<asp:LinkButton ID="ActiveSideBarButton" runat="server">
<asp:LinkButton Visible="false" ID="SideBarButton"unat="server"/>
</SelectedItemTemplate>
In OnItemDataBound event do something like
Dim stepCurrent As WizardStep = e.Item.DataItem
If stepCurrent.Wizard.ActiveStepIndex = e.Item.ItemIndex Then
Dim linkCurrent As LinkButton = e.Item.FindControl("ActiveSideBarButton")
linkCurrent.Style.Add(HtmlTextWriterStyle.Color, "#000000")
linkCurrent.Style.Add(HtmlTextWriterStyle.FontWeight, "bold")
LinkCurrent.Text = stepCurrent.Title;
linkCurrent.Text.Insert(0, ">> ")
End If
SideBarButton will not be rendered because of visible="false" and only ActiveSideBarButton for current step will be rendered with parameters you need.

AutoCompleteExtender control in a repeater

I have an AutoCompleteExtender AjaxControlToolkit control inside a repeater and need to get a name and a value from the web service. The auto complete field needs to store the name and there is a hidden field that needs to store the value. When trying to do this outside of a repeater I normally have the event OnClientItemSelected call a javascript function similiar to
function GetItemId(source, eventArgs)
{
document.getElementById('<%= ddItemId.ClientID %>').value = eventArgs.get_value();
}
However since the value needs to be stored in a control in a repeater I need some other way for the javascript function to "get at" the component to store the value.
I've got some JavaScript that might help you. My ASP.Net AutoComplete extender is not in a repeater, but I've modified that code to detect the ID of the TextBox you are going to write the erturned ID to, it should work (but I haven't tested it all the way through to post back).
Use the value from 'source' parameter in the client side ItemSelected method. That is the ID of the calling AutoComplete extender. Just make sure that you assign an ID the hidden TextBox in the Repeater Item that is similar to the ID of the extender.
Something like this:
<asp:Repeater ID="RepeaterCompareItems" runat="server">
<ItemTemplate>
<ajaxToolkit:AutoCompleteExtender runat="server"
ID="ACE_Item"
TargetControlID="ACE_Item_Input"
...other properties...
OnClientItemSelected="ACEUpdate_RepeaterItems" />
<asp:TextBox ID="ACE_Item_Input" runat="server" />
<asp:TextBox ID="ACE_Item_IDValue" runat="server" style="display: none;" />
</ItemTemplate>
</asp:Repeater>
Then the JS method would look like this:
function ACEUpdate_CustomerEmail(source, eventArgs) {
UpdateTextBox = document.getElementById(source.get_id() + '_IDValue');
//alert('debug = ' + UserIDTextBox);
UpdateTextBox.value = eventArgs.get_value();
//alert('customer id = ' + UpdateTextBox.value);
}
There are extra alert method calls that you can uncomment for testing and remove for production. In a simple and incomplete test page, I got IDs that looked like this: RepeaterCompareItems_ctl06_ACE_Item_IDValue (for the text box to store the value) and RepeaterCompareItems_ctl07_ACE_Item (for the AC Extender) - yours may be a little different, but it looks practical.
Good Luck.
If I understand the problem correctly, you should be able to do what you normally do, but instead of embeding the ClientId, use the 'source' argument. That should allow you to get access to the control you want to update.
Since you are using a Repeater I suggest wiring the OnItemDataBound function...
<asp:Repeater id="rptResults" OnItemDataBound="FormatResults" runat="server">
<ItemTemplate>
<asp:PlaceHolder id="phResults" runat="server" />
</ItemTemplate>
</asp:Repeater>
Then in the code behind use something like
`Private Sub FormatResults(ByVal sender As Object, ByVal e As RepeaterItemEventArgs)
Dim dr As DataRow = CType(CType(e.Item.DataItem, DataRowView).Row, DataRow) 'gives you access to all the data being bound to the row ex. dr("ID").ToString
Dim ph As PlaceHolder = CType(e.Item.FindControl("phResults"), PlaceHolder)
' programmatically create AutoCompleteExtender && set properties
' programmatically create button that fires desired JavaScript
' use "ph.Controls.Add(ctrl) to add controls to PlaceHolder
End Sub`
Voila

Resources