I databing array of User objects to GridView control. Last column contains "action" anchors (edit, remove):
<asp:TemplateField HeaderText="Actions">
<ItemTemplate>
Remove
Edit
</ItemTemplate>
</asp:TemplateField>
However I would like not to output first anchor to Remove action if currently binded User object has the same id as use logged in (available with this.SessionUser.Id).Something like this:
<asp:TemplateField HeaderText="Actions">
<ItemTemplate>
Remove
if (this.SessionUser.Id <> Eval("user_id") { Edit }
</ItemTemplate>
</asp:TemplateField>
How can I do it?
Thanks!
You can use a runat="server" control for this
<asp:TemplateField HeaderText="Actions">
<ItemTemplate>
Remove
<a href="Edit.aspx?id=<%# Eval("user_id") %>" runat="server"
visible='<%# this.SessionUser.Id <> Eval("user_id") %>'>Edit</a>
</ItemTemplate>
</asp:TemplateField>
All server controls, even HTML tags with runat="server" have this Visible property, which omits the control from the final HTML when it is false.
not supported :( you need to write another function passing it user_id and get the appripriate string from it like this:
//in cs file
protected string GetLink(object o)
{
if(!SessionUser.Id.Equals(o)) //or anyother way to compare equality
return string.Format("<a href=\"Edit.aspx?id={0}\">",0);
return "";
}
//in aspx file
<ItemTemplate>
Remove
<%# GetLink(Eval("user_id"))%>
</ItemTemplate>
you can use CSS:
<a style='visible:<%# this.SessionUser.Id <> Eval("user_id") %>' > ... </a>
make sure that this.SessionUser.Id is a public variable in your .cs file
Related
I have seen many resources on SO that say that I can use following syntax to pass value to CommandArguement of `LinkButton'
<%forearch(var comment in Comments){%>
<asp:LinkButton ID="del" CommandArguement='<%= comment.CommentId%>' onCommand="delete_click" Text="Delete"/>
<%}%>
But when I write this in my ascx file and click on the link the value passed to command argument is "<%=comment.CommentId%>" instead of commentId itself. Please guide what am I doing wrong?
Edit 1
based on answers and comments, I have moved to use repeater instead of foreach and plain code. Here is the code I have come up with
<asp:Repeater ID="commRepeater" SelectMethod="GetPageComments" runat="server">
<ItemTemplate>
<p>
<%#Eval("Comment") %>
<%if(Page.User.Identity.IsAuthenticated && Page.User.Identity.GetUserId() == Eval("UserId")){ %>
<span>
<asp:LinkButton Text="Edit" runat="server" ID="EditLink" CommandArgument='<%#Eval("CommentId")%>' OnClick="Update_Comment" />
<asp:LinkButton Text="Delete" runat="server" ID="DeleteLink" CommandArgument='<%#Eval("CommentId")%>' OnClientClick="if (!confirm('Are you sure you want delete?')) return false;" OnCommand="Delete_Comment" />
</span>
<%} %>
</p>
</ItemTemplate> </asp:Repeater>
you can see that I am trying to show the edit and delete links if user is logged in and his Id matches with user who commented but it tells me that I can on use Eval in databound controls. how would I hide/show edit/delete links conditionally within repeater
You could simply use codebehind, for example in Page_Load:
protected void Page_Load(Object sender, EventArgs e)
{
if(!IsPostBack)
{
del.CommandArgument = comment.CommentId;
}
}
Maybe a better approach would be to use the Comments-collection(which seems to be a list or array of a custom class) as DataSource of a Repeater(or other web-databound control). Then you can add the LinkButtons to the Itemtemplate.
You can then either use ItemCreated or ItemDataBound events of the repeater in codebehind or inline ASP.NET tags to bind the CommandArgument.
For example:
CommandArguement='<%# DataBinder.Eval( Container.DataItem, "CommentId" ) %>'
What you are doing currently is not recommended and is highly error prone. You can easily achieve this with ASP.NET Repeater control like this:-
<asp:Repeater ID="MyRepeater" runat="server">
<ItemTemplate>
<asp:LinkButton ID="del" CommandArguement='<%# Eval("CommentId") %>'
OnCommand="del_Command" Text="Delete" runat="server" />
</ItemTemplate>
</asp:Repeater>
In Page_Load simply bind it:-
if (!Page.IsPostBack)
{
MyRepeater.DataSource = CommentsRepository();
MyRepeater.DataBind();
}
Or Else if you are have ASP.NET 4.5 then use strongly type Data Bound controls like this:-
<asp:Repeater ID="MyRepeater" runat="server" ItemType="MyNamespace.Comment"
SelectMethod="MyRepeater_GetData">
<ItemTemplate>
<asp:LinkButton ID="del" CommandArguement='<%# Item.CommentId %>'
OnCommand="del_Command" Text="Delete" runat="server" />
</ItemTemplate>
</asp:Repeater>
And you method in code behind should be something like this(just for Demo):-
public IEnumerable<MyNamespace.Comment> MyRepeater_GetData()
{
return new List<Comment>
{
new Comment { CommentId =1, Name= "foo"},
new Comment { CommentId =2, Name= "bar"},
};
}
I have a label within an Edit Template for a gridview which goes like this:
<asp:Label ID="lblProjectID" runat="server" Text='<%# Bind("Project_ID") %>'></asp:Label>
I would like to turn that label text into a http link like so:
<asp:Label ID="lblProjectID" runat="server" Text='<a href=http://intranet/?<%# Bind("Project_ID") %>> <%# Bind("Project_ID") %></a>'></asp:Label>
So the link would look something like http://intranet/?Project_ID
But that syntax is incorrect. What is the correct way to write that?
This is what you can do on your Label tag.
<asp:TemplateField>
<ItemTemplate>
<a href='<%# String.Format("http://intranet/?Project_ID={0}", Eval("Project_ID")) %>'><%# Eval("Project_ID")%></a>
</ItemTemplate>
</asp:TemplateField>
If you want it to be a link... then just use a link, not a label:
<a href='http://intranet/?<%# Eval("Project_ID") %>'><%# Eval("Project_ID")%></a>
or same thing with HyperLinkField (if you want to use it as a column and not inside EditItemTemplate:
<asp:HyperLinkField DataTextField="Project_ID" DataNavigateUrlFields="Project_ID" DataNavigateUrlFormatString="http://intranet/?{0}" />
I want to show "N/A" text in grid view label if value is not available in database and if it is available, then the value should be displayed instead of "N/A".
How can I customize my label?
This is the code that I have written to get the value.
<asp:Label ID="lblCineRunFrom" runat="server" Text='<%# Eval("CineRunFrom") %>'></asp:Label>
This works:
<asp:Label id="dada" runat="server" Text='<%# string.Format("{0}",string.IsNullOrEmpty(Eval("CineRunFrom").ToString())?"N/A":Eval("CineRunFrom")) %>' ></asp:Label>
You may use this: Text='<%# Eval("CineRunFrom")?? "N/A" %>'
Add a new function in code behind & call it from HTML code, check sample code below.
Code
Private Function GetDisplayText(ByVal CineRunFrom As String) As String
'Do whatever you want here and return text to dispaly as required
End Function
HTML
<asp:Label ID="lblCineRunFrom" runat="server" Text='<%# GetDisplayText(Eval("CineRunFrom")) %>'></asp:Label>
I have a gridview with a hyperlink inside an TemplateField. The NavigateUrlFormat will be populated from the Web.Config file, it has the following format:
mysite.com/{0}
Where {0} will be populated from the gridview datasource, however, my current code doesn't work:
<asp:TemplateField HeaderText="WorkOrder #">
<ItemTemplate>
<asp:HyperLink ID="HyperLink1" runat="server"
NavigateUrl='<%# Eval("WorkOrderKey", "<%$ AppSettings:DispatchLink %>") %>'
Text='<%# Eval("WorkOrderKey") %>'></asp:HyperLink>
</ItemTemplate>
</asp:TemplateField>
The problem is right after "AppSettings:DispatchLink", it closes the tag when it see "%>". Is there a way around this problem?
Thank you,
Kenny.
You cannot nest <%# and other tags. Use ConfigurationManager.AppSettings["DispatchLink"] (pls. lookup correkt Class/Property in MSDN) instead.
Or: If your are using that HyperLink Control more than once I would suggest that you create an own MYHyperLink derived from System.Web.UI.WebControls.HyperLink and set the Property NavigateUrlFormatString in your Constructor.
Something like this:
public class DispatchLink : System.Web.UI.WebControls.HyperLink
{
public DispatchLink()
{
this. NavigateUrlFormatString = ConfigurationManager.AppSettings["DispatchLink"]
}
}
OK I have a GridView and there is a column that I want to be a link if a file exists, otherwise I just want it to be a label. Right now I am changing the controls on RowDataBound event handler using the Row passed in the args. I am not a big fan of this as I am hard coding the column ID, and if it ever changes I will need to remember to change this code. I was hoping I could do a conditional in the asp code to add a link if a property value is not null otherwise add a label. Is this possible? Any different solutions?
I would like something like this:
<asp:TemplateField HeaderText="Status">
<ItemTemplate>
<%# if (Eval("LogFileName") == null)
<%#{
<asp:LinkButton ID="LogFileLink" runat="server" CommandArgument='<% #Eval("LogFileName") %>' CommandName="DownloadLogFile" Text='<%# Blah.NDQA.Core.Utilities.GetEnumerationDescription(typeof(Blah.NDQA.Core.BatchStatus), Eval("Status")) %>'>
<%# }
<%# else
<%#{
<asp:Label ID="LogFileLabel" runat="server"Text='<%# Blah.NDQA.Core.Utilities.GetEnumerationDescription(typeof(Blah.NDQA.Core.BatchStatus), Eval("Status")) %>'>
</asp:Label>
</ItemTemplate>
</asp:TemplateField>
You can continue to use RowDataBound event but in your aspx you add:
<asp:PlaceHolder ID="PlaceHolder1" runat="server"></asp:PlaceHolder>
In your C# code something like that:
if (LogFileName) {
LinkButton ctrl = new LinkButton();
ctrl.CommandArgument= ...;
ctrl.CommandName= ...;
} else {
Label ctrl = new Label();
ctrl.Text= ...;
}
// You have to find the PlaceHolder1
PlaceHolder1.Controls.Add(ctrl);
In this way you don't have to hard coding the column ID
I know this is a little old now but just in case someone else stumbles across this as I did when looking for an answer to a similar question, I found you can do something like this:
<ItemTemplate>
<asp:ImageButton ID="btnDownload" runat="server"
CommandName="Download"
CommandArgument='<%# Eval("Document_ID") & "," & Eval("Document_Name") %>'
ImageUrl="download.png" ToolTip='<%#"Download " & Eval("Document_Name") %>'
Visible='<%# Not(Eval("Document_ID") = -1) %>' />
</ItemTemplate>
i.e. set the Visible property to evaluate a boolean expression based on your field. If you wanted to display something instead of the download link or button, such as a "Not available" label, then you would just set its Visible property to the opposite boolean expression to your download link. (This is VB.NET not C#, but you get the idea.)
If you're going to be doing this a lot, I suggest writing your own field. The simplest approach is probably to make a NullableHyperlinkField inheriting from HyperlinkField, and render out a plain string if the anchor's URL would otherwise be null.
Use properties on the page to determine if you want to show the label or the link
<asp:GridView ID="gv" runat="server">
<Columns>
<asp:TemplateField HeaderText="Status">
<ItemTemplate>
<asp:LinkButton runat="server" Visible='<%# ShowLink %>' PostBackUrl="~/Aliases.aspx" >This is the link</asp:LinkButton>
<asp:Label runat="server" Visible='<%# ShowLabel %>'>Aliases label</asp:Label>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
The add the properties ShowLink and ShowLable toyour code behind
public bool ShowLabel
{
get
{
//determine if the label should be shown
return false;
}
private set
{
//do nothing
}
}
public bool ShowLink
{
get
{
//determine if the link should be shown
return true;
}
private set
{
//do nothing
}
}