Show/Hide buttons based on inline code while looping - asp.net

I'm trying to figure out how to use a temporary variable (created from a loop) to show/hide a button.
I have tabular data and some action buttons to the side of them. I need to be able to turn buttons off and on based on the state of that data.
f.IsFoo is a boolean
<table stuff here>
<% foreach (Foo f in listOfFoos) { %>
<tr>
<td>
<%= Fubar(f)%>
</td>
<td>
<%= Fubar1(f) %>
</td>
<td>
<%= Fubar2(f)%>
</td>
<td>
<%= Fubar3(f)%>
</td>
<td>
<%= Fuba4(f)%>
</td>
<td>
<%= Fubar5(f)%>
</td>
<td>
<asp:Button Text="Load" runat="server" OnClick="FooBar" Visible='<%= f.IsFoo%>'/>
</td>
</tr>
<%}%>
I'm pretty new to aspx and it's syntax and online searches have just confused me more.

Personally I tend to put logic like this in the code behind file - however I believe the code below should work,
I added an ID to your button - and I also removed the visibility property - I'm then referencing the button, by its ID - and setting its visibility equal to that of the f.IsFoo property
Possibly try this here:
<% btnFoo.Visible = f.IsFoo; %>
<asp:Button ID="btnFoo" Text="Load" runat="server" OnClick="FooBar" />

Related

ASP Nested Repeater IDs

I'm using bootstrap to collapse and expand a table, which is working fine but I'm using classes instead of IDs. With this, expanding one row expands all the rows rather than just that one. My question is how does my data-target point at a nested repeater id? The transactionCollapse ID is unable to be targeted directly and I've tried doing <%=transactionGroupedList.FindControl("transactionCollapse")%> but it threw an error.
<tbody>
<asp:Repeater runat="server" ID="transactionGroupedList" OnItemDataBound="TransactionGroupedDataList_ItemDataBound">
<ItemTemplate>
<tr>
<!-- This line should target the transactionCollapse ID below instead of the class -->
<td data-toggle="collapse" data-target=".transactionCollapse">
<span id="transactionGroupCollapseIcon" runat="server" class="fonticon-down-arrow"></span>
<custom:Label runat="server" ID="transactionActivityDataColumnLabel"></custom:Label>
</td>
<td>
<custom:Label runat="server" ID="transactionDateDataColumnLabel">
</custom:Label>
</td>
<td>
<custom:Label runat="server" ID="transactionNumberDataColumnLabel">
</custom:Label>
</td>
<td>
<custom:Label runat="server" ID="transactionAmountDataColumnLabel">
</custom:Label>
</td>
<td>
<custom:Label runat="server" ID="transactionStatusDataColumnLabel">
</custom:Label>
</td>
</tr>
<asp:Repeater runat="server" ID="transactionDetailList" OnItemDataBound="TransactionDetailsDataList_ItemDataBound">
<ItemTemplate>
<tr id="transactionCollapse" runat="server" class="collapse transactionCollapse">
<td colspan="2">
<custom:Label runat="server" ID="transactionDetail">
</custom:Label>
</td>
<td>
<custom:Label runat="server" ID="transactionDetailTransactionNumber">
</custom:Label>
</td>
<td>
<custom:Label runat="server" ID="transactionDetailAmount">
</custom:Label>
</td>
</tr>
</ItemTemplate>
</asp:Repeater>
</ItemTemplate>
</asp:Repeater>
</tbody>
The Online Payment row is what collapses/expands the Posting - and MP Payment rows below. This user only has one Online Payment, but many users will have multiple.
You have a couple of problems. First of all when using FindControl inside a Repeater/GridView etc is index based. So you need to use FindControl on the correct Item.
transactionGroupedList[i].FindControl("transactionCollapse")
However the above will still not work because transactionCollapse is in a nested Repeater that needs to be found first and then access the correct Item Index.
transactionGroupedList.Items[0].FindControl("transactionDetailList").Items[0]...
But this will also not work since FindControl does not know that transactionDetailList is a Repeater with index based Items. So you need to cast the nested Repeater first before you can access it's items. So it becomes this
<%= ((Repeater)transactionGroupedList.Items[i].FindControl("transactionDetailList")).Items[i].FindControl("transactionCollapse").ClientID %>

ASP.NET - IF Statement in Listview doesnt work on aspx page, is there an alternative?

I have bound a DataSet to a ListView. In the ListView ItemTemplate, if a row value is empty, I do not want it, or the <td> element it is enclosed in to display.
In my code, the first row value will display. However, when I try to use the If statement on the second <td> element, that will not display.
<asp:ListView ID="ListView1" runat="server" GroupPlaceholderID="groupPlaceHolder1" ItemPlaceholderID="itemPlaceHolder1">
<LayoutTemplate>
<table>
<asp:PlaceHolder runat="server" ID="groupPlaceHolder1"> </asp:PlaceHolder>
</table>
</LayoutTemplate>
<GroupTemplate>
<tr>
<asp:PlaceHolder runat="server" ID="itemPlaceHolder1"> </asp:PlaceHolder>
</tr>
</GroupTemplate>
<ItemTemplate>
<td>
<%# Eval("textItem1") %>
</td>
<% if (!String.IsNullOrEmpty(textItem2){ %>
<td>
<%# Eval("textItem2") %>
</td>
<%} %>
</ItemTemplate>
</asp:ListView>
That If statement works in an aspx page if its NOT being used in a ListView, Repeater, or GridView (or does it?). I need to be able to check if that string row value is empty and not display it or the <td> element it is enclosed in. I am not against a solution that uses code-behind. Is there another way to do this then my attempt?
I used a pretty simple method solution..
In the above code, I swapped out this...
<% if (!String.IsNullOrEmpty(textItem2){ %>
<td>
<%# Eval("textItem2") %>
</td>
<%} %>
For this...
<%# writeText(Eval("textItem2").ToString())%>
And placed this method in the code behind...
public string writeText(string kiss)
{
if (!String.IsNullOrEmpty(kiss))
return "<td> " + kiss + "</td>";
else
return null;
}

Don't render HTML element, if DataBinder.Eval(Container.DataItem, "someValue") == 0

I have a <asp:repeater> inside which i'm rendering a table with a few rows.
Each row - corresponding to a different value.
Question: how to "skip" the row, in case this value is empty?
here is evaluation statement:
<%# DataBinder.Eval(Container.DataItem, "Website") == ""? "" : /*render element*/ %>
and here is element i want to render in case statement if false:
<tr>
<td><span>Website address:</span></td>
<td>
<p><%#DataBinder.Eval(Container.DataItem, "Website") %></p>
</td>
</tr>
Try this:
<asp:Repeater runat="server" id="myRepeater">
<ItemTemplate>
<tr runat="server"
visible='<%#String.Format("{0}",DataBinder.Eval(Container.DataItem, "Website"))!="" %>'>
<td><span>Website address:</span></td>
<td>
<p><a href='<%#DataBinder.Eval(Container.DataItem, "Website") %>"
class="red-link'><%#DataBinder.Eval(Container.DataItem, "Website") %></a></p>
</td>
</tr>
</ItemTemplate>
</asp:Repeater>
It will set the row's visible attribute to false when the Website is empty or null.

ASp.Net repeater control : error showing on binding repeater

It shows error "Non-invocable member 'System.Web.UI.WebControls.RepeaterItem.DataItem' cannot be used like a method.
for the <%# Container.DataItem("CostPageDescription")%>
my code below,
<td> Cost Page Description</td>
<td> Vendor Name</td>
<td> Bill Type</td>
</tr>
</HeaderTemplate>
<ItemTemplate>
<tr>
<td> <%# Container.DataItem("CostPageDescription")%></td>
<td> <%# Container.DataItem("VendorName")%> </td>
<td> <%# Container.DataItem("BillType") %> </td>
</tr>
<tr>
USE LIKE THIS
<td> <%# eval("CostPageDescription")%></td>
and at one place u left it blank, so make that correct
Use this:
<%# Eval("CostPageDescription") %>
or this:
<%# DataBinder.Eval(Container.DataItem, "CostPageDescription") %>
First one is just a simplification of the second.

How to a use a web user control more than one time on the same page?

I have created web user control for calendar. I.e it has a textbox and a calendar image. By clicking on calendar popup the calendar opens. Then by selecting any date it stores the year of that date. I use this code:
<script language="javaScript" type="text/javascript" src="Scripts/Calendar.js"> </script>
<link href="Styles/Calendar.css" rel="stylesheet" type="text/css" />
<table>
<tr>
<td>
<input type="text" name="datum1"/>
</td>
<td>
<img id="Img1" src="images/calFinal.jpg" alt="" runat="server" onclick="setYears(1947, 2040);
showCalender(this, 'datum1');" />
</td>
</tr>
</table>
<div>
<!-- Calender Script -->
<table id="calenderTable">
<tbody id="calenderTableHead">
<tr>
<td colspan="4" align="center">
<select onchange="showCalenderBody(createCalender(document.getElementById('selectYear').value,
this.selectedIndex, false));" id="selectMonth">
<option value="0">Jan</option>
<option value="1">Feb</option>
<option value="2">Mar</option>
<option value="3">Apr</option>
<option value="4">May</option>
<option value="5">Jun</option>
<option value="6">Jul</option>
<option value="7">Aug</option>
<option value="8">Sep</option>
<option value="9">Oct</option>
<option value="10">Nov</option>
<option value="11">Dec</option>
</select>
</td>
<td colspan="2" align="center">
<select onchange="showCalenderBody(createCalender(this.value,
document.getElementById('selectMonth').selectedIndex, false));" id="selectYear">
</select>
</td>
<td align="center">
<font color="#003333" size="+1">X</font>
</td>
</tr>
</tbody>
<tbody id="calenderTableDays">
<tr style="">
<td>Sun</td>
<td>Mon</td>
<td>Tue</td>
<td>Wed</td>
<td>Thu</td>
<td>Fri</td>
<td>Sat</td>
</tr>
</tbody>
<tbody id="calender">
</tbody>
</table>
<!-- End Calender Script -->
</div>
The problem occurs when I use the user control twice on the same web form. I have registered the control. When I use it once, it works proper. But I want it at two places. So, please give some solution on how to use the user control more than one time on the same web form. I have given different IDs for the user control, but it still does not work.
Code for user control:
<tr>
<td class="directorytdWidth directorylabel">
School Name:
</td>
<td class="directoryTdPadding">
<asp:TextBox ID="txtSchoolName" runat="server" Width="120px" ForeColor="#FF9F00"></asp:TextBox>
</td>
</tr>
<tr>
<td class="directorytdWidth directorylabel">
School Passout Year:
</td>
<td class="directoryTdPadding">
<uc1:calendar ID="schoolPassout" runat="server" />
</td>
</tr>
<tr>
<td class="directorytdWidth directorylabel">
College Name:
</td>
<td class="directoryTdPadding">
<asp:TextBox ID="txtCollegeName" runat="server" Width="120px" ForeColor="#FF9F00"></asp:TextBox>
</td>
</tr>
<tr>
<td class="directorytdWidth directorylabel">
College Passout Year:
</td>
<td class="directoryTdPadding">
<uc1:calendar ID="collegePassout" runat="server" />
</td>
</tr>
Use the Same User control but With diferent ID. For example (See code below)
Reg Your User control in you Web page
<%# Register Src="~/Controls/SearchAffiliated.ascx" TagPrefix="uc" TagName="SearchAffiliated" %>
First User Control call
<uc:SearchAffiliated runat="server" ID="ucSearchAffiliated" />
Second User Control Call
<uc:SearchAffiliated runat="server" ID="SearchAffiliated1" />
See The Users Controls have diferents IDs, That Works For call The same UC in one web form.
Cheers.
Use the loop of how many times that u want the usercontrol to display:
for(int i=0;i < n; i++) //Define the number of time that u want to display
{
usercontrolname.id="UC"+i;//Assign the id for that usercontrol
//add line of code,that controls in placeholder or panel
}
You can use same user control in same page in N number of times. either it dynamically or statically. Only the thing is we need to give the different ID for the usercontrol
This need to add in your Reg
<%# Register Src="~/UserControls/Hello.ascx" TagPrefix="uc" TagName="Hello" %>
calling the user control 1
<uc:Hello runat="server" ID="ucHello1" />
calling the user control 2
<uc:Hello runat="server" ID="ucHello2" />
I faced same problem but the problem was not related with the ID you prefer to use inside the asp.net page. Because I guess asp.net automatically generates ID for each element in page if it doesn't have one.
The problem was I copied ascx files and forget to change their class names. Make sure you use different class names for each user control.
<%# Control Language="C#" ClassName="ucSchema2" %>
I know this i late to the game but maybe someone can use this answer anyway.
Using a static clientside id for a html element in a user control and then using that user control multiple times will results in invalid html.
You are only allowed to use an id once on a html page otherwise getElementById (which returns a single element) will not know which element to get and then you will probably not get any element whatsoever.
You need to make those clientside ids inside the user control truely unique, i.e. selectMonth, selectYear.
This might be done by appending the ClientID of the user control to the element id. Something like this (not sure if this approach really works but you get the idea):
<select onchange="showCalenderBody(createCalender(document.getElementById('selectYear_<%=this.ClientID%>').value,
this.selectedIndex, false));" id="selectMonth_<%=this.ClientID%>">
This way the clientside id should be a combination of locally unique ids and the page unique control ids.

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