How to use ternary operator in razor specifically on HTML attributes

Question

With the WebForms view engine  I ll commonly use the ternary operator for very simple conditionals  especially within HTML attributes  For example    lt a class   lt   User Identity IsAuthenticated    auth     anon    gt   gt My link here lt  a gt    The above code will give the  lt a gt  tag a class of auth or anon depending on whether the user is authenticated   What is the equivalent syntax with the Razor view engine  Because Razor requires HTML tags to  know  when to jump in and out of code and markup  I m currently stuck with the following    if User Identity IsAuthenticated      lt a class  auth  gt My link here lt  a gt    else    lt a class  anon  gt My link here lt  a gt      This is  to put it mildly  terrible    I would love to do something like this  but am struggling to understand how in Razor    lt a class    User Identity IsAuthenticated    auth     anon    gt My link here lt  a gt    --  Update   In the meantime  I ve created this HtmlHelper   public static MvcHtmlString Conditional this HtmlHelper html  Boolean condition  String ifTrue  String ifFalse      return MvcHtmlString Create condition   ifTrue   ifFalse       which can be called like this from Razor    lt a class   Html Conditional User Identity IsAuthenticated   auth    anon    gt My link here lt  a gt    Still  I am hoping there s a way to use the ternary operator without falling back to wrapping it in an extension method

User · Accepted Answer

You should be able to use the     expression syntax   lt a class  quot   User Identity IsAuthenticated    quot auth quot     quot anon quot   quot  gt My link here lt  a gt

User · Answer

Addendum   The important concept is that you are evaluating an expression in your Razor code   The best way to do this  if  for example  you are in a foreach loop  is using a generic method     The syntax for calling a generic method in Razor is     expression    In this case  the expression is   User Identity IsAuthenticated    auth     anon    Therefore  the solution is     User Identity IsAuthenticated    auth     anon     This code can be used anywhere in Razor  not just for an html attribute   See  Kyralessa  s comment for C  Razor Syntax Quick Reference  Phil Haack s blog

User · Answer

A simpler version  for easy eyes     true  yes   no

User · Answer

You can also use this method    lt input type  text  class     mvccondition    true-class     false-class    gt    Try this    Good luck Thanks

User · Answer

in my problem I want the text of anchor  lt a gt text lt  a gt  inside my view to be based on some value and that text is retrieved form App string Resources  so  this     is the solution    lt a href     gt          Model ID    0   Resource en Back   Resource en Department View DescartChanges   lt  a gt    if the text is not from App string Resources use this    Model ID    0    Back    Descart Changes

User · Answer

For those of you who use ASP net with VB razor the ternary operator is also possible   It must be  as well  inside a razor expression      Razor Expression    and the ternary operator works as follows   If BooleanTestExpression   TruePart    FalsePart     The same code example shown here with VB razor looks like this     lt a class    If User Identity IsAuthenticated   auth    anon     gt My link here lt  a gt    Note  when writing a TextExpression remember that Boolean symbols are not the same between C  and VB

User · Answer

I have a field named IsActive in table rows that s True when an item has been deleted  This code applies a CSS class named strikethrough only to deleted items  You can see how it uses the C  Ternary Operator   lt tr class  quot    businesstypes IsActive    quot  quot     quot strikethrough quot   quot  gt

[razor] How to use ternary operator in razor (specifically on HTML attributes)?

Examples related to razor

Examples related to asp.net-mvc-3