This is a pretty simple question I can’t find the answer to…
Obviously <%= %> directs the output of all the commands inside the block
to the html file being generated.
that works fine with rails helpers and variables, but what if I simply
want to output a string if a certain condition was met?
e.g:
<%= @user.nil? “not logged in” : @user.name%>
so if the user is not logged an appropraite text is echoed.
I’ve tried print (which ends up doing strange things) and puts (which
gives me a 500 error no less).
How is this done?
Thanks,
Ehud
PS - I know I can break this up so the text would no be inside the erb
code, but that ends up with some really ugly code.
This should do it:
<%= “non logged in” unless @user -%>
Or you could create a helper method in application_helper:
def log_on_status(user=nil)
if user
return “Logged on as #{user.name}”
else
return “User not logged on”
end
end
And then in the view enter
<%= log_on_status(@user) -%>
Rob N. wrote:
This should do it:
<%= “non logged in” unless @user -%>
Or you could create a helper method in application_helper:
def log_on_status(user=nil)
if user
return “Logged on as #{user.name}”
else
return “User not logged on”
end
end
And then in the view enter
<%= log_on_status(@user) -%>
the “-” at the end ( -%> ) makes this possible?
Is there no way to just echo a string to the screen?
Hi,
<%= @user.nil? “not logged in” : @user.name%>
so if the user is not logged an appropraite text is echoed.
I’ve tried print (which ends up doing strange things) and puts (which
gives me a 500 error no less). How is this done?
your approach is good, but you got misleaded by the question mark.
nil? is a method of object, so the whole name of the method is nil?,
with the question mark included.
if you want to use the operator ? the syntax is
condition ? result_if_true : result_if_false
the trick here is that in your case the condition would be @user.nil?
and then the syntax would be
<%= @user.nil? ? “not logged in” : @user.name%>
notice the extra ? you didn’t have before. So… you were really close.
Because of ruby accepting ? as a method name i had a hard time at the
beginning using the ? operator coming from other languages. Finally I
got used to use it always like
(condition) ? (if_true) : (if_false)
this way, by using the brackets, it makes easier to have the right
syntax at the first try 
And, anyway, to complete the answer to your question… for really
really really special cases where you cannot just use <%=%> syntax for
some obscure reason (usually complex helpers with blocks), you could use
the concat method. As documentation says, the <%=%> standard erb syntax
is preferred.
Regards,
javier ramirez
–
Estamos de estreno… si necesitas llevar el control de tus gastos
visita http://www.gastosgem.com !!Es gratis!!
Matthew I. wrote:
Ehud R. wrote:
the “-” at the end ( -%> ) makes this possible?
Is there no way to just echo a string to the screen?
The “-” is just supressing a newline in the HTML output. It has no
affect on the logic.
This echoes a string:
<%= “string” %>
The use of -%> is a style thing. I tend to use it situations like this
where just a small bit of text is being dynamically inserted. I use it
because I think the resulting HTML is neater, easier to read and
therefore easier to debug. If you don’t use it a newline gets added
after each dynamic entry. For example:
<%= "string" %>
outputs:
string
Whereas
<%= "string" -%>
outputs:
string
Ehud R. wrote:
Rob N. wrote:
This should do it:
<%= “non logged in” unless @user -%>
Or you could create a helper method in application_helper:
def log_on_status(user=nil)
if user
return “Logged on as #{user.name}”
else
return “User not logged on”
end
end
And then in the view enter
<%= log_on_status(@user) -%>
the “-” at the end ( -%> ) makes this possible?
Is there no way to just echo a string to the screen?
The “-” is just supressing a newline in the HTML output. It has no
affect on the logic.
This echoes a string:
<%= “string” %>
(thought it isn’t very useful, obviously because it is just a static
string)
This conditionally echoes a string:
<%= “string” if @user %>
-matthew