What is the difference between <% %> and <%= %> in ASP.NET MVC [duplicate]

Answer 1

<%= %> tag prints the output of the code in it, <% %> just runs the code.

Answer 2

<% %> is a generic code block.

<%= expression %> is equivalent to <% Response.Write(expression); %>.

Answer 3

Mehrdad's comment about <%$ piqued my curiosity, so I found this inline asp.net tags list by googling "asp.net inline code" (sans quotes). It has msdn links and descriptions of all the inline tags (<%, <%=, <%#, <%$, <%@, <%--).

Answer 4

It is confusing, and it takes a good deal of repetition to get comfortable with.

The <%= syntax is used for evaluating expressions whose returned values are intended to be included within HTML markup. For example:

<%= DateTime.Now.ToShortDateString() %>

This will include the current date in the HTML markup.

The <% is for inline statements, where you want to execute one or more commands at a specific point during the page rendering. I've used Html Helpers in the past by executing the helper method using <%. For example,

<% Html.TextBox("txtBox"); %>

Note that the statements used here have to be terminated with a semicolon in C# code.

EDIT: Removed erroneous details about Html helpers and void returns.

Answer 5

This post lists all the varieties nicely: ASP.NET "special" tags.

I would normally post this as a comment but there are a number of other dupes. I recall someone referring to them as "bee stings" (not official terminology) and the keywords I used to search for them were asp.net bee stings.

That said, here are some other dupes:

• What is the difference between <% %> and <%=%>?
• <%$, <%@, <%=, <%#…what’s the deal?
• When should I use # and = in ASP.NET controls?