I've run into a couple different exceptions with this block of code in one of my views:
<% if (Model.Book.ReviewReference == null)
{%>
<%=Html.ActionLink("Rate / review this book", "Create", "Review", null, new { id = "reviewLink" }) %>
<% Html.RenderPartial("CreateReview");
}
else
{%>
<%= Html.ActionLink("Edit this开发者_如何转开发 book's rating / review","Edit", "Review", new { reviewID = Model.Book.ReviewID}, new {id = "reviewLink"}) %>
<% Html.RenderPartial("EditReview", Model.Book.Review, new ViewDataDictionary());
} %>
The first error I encountered was described here: link text
thus the Html.RenderPartial("EditReview", Model.Book.Review, new ViewDataDictionary())
you see towards the end there.
Another problem I encountered is when the if condition is evaluated for a ReviewReference
that is in fact null
, the else statement is still being reached somehow, and the second partial view is making an unsuccessful attempt to render itself.
Have I used these alternating inline-code tags in an incorrect manner? How does one go back and forth between <% %>
and <%= %>
properly?
Thank you.
Edit:
OK, I marked an answer too soon. I just tried it with the given code from the answer, and that else block is still being evaluated, and trying to pass null objects to the partial view...darn it.
You are correct in your usage of the tags there.
They aren't 2 alternating styles, but differences in how the view engine deals with different statements. It's not surprising that it can get confusing.
<%=
: Think of this as Response.Write()
. You supply it with a string.
<% Html.RenderPartial
- this is a command given to the view engine to actually render a partial view. You're not giving it a string, but rather telling the view to go get another snippet (partial view), and write it out.
Missing a couple of closing %>
<% if (Model.Book.ReviewReference == null)
{%>
<%=Html.ActionLink("Rate / review this book", "Create", "Review", null, new { id = "reviewLink" }) %>
<% Html.RenderPartial("CreateReview"); %>
<%}
else
{%>
<%= Html.ActionLink("Edit this book's rating / review","Edit", "Review", new { reviewID = Model.Book.ReviewID}, new {id = "reviewLink"}) %>
<% Html.RenderPartial("EditReview", Model.Book.Review, new ViewDataDictionary()); %>
<% } %>
OK, so it turns out my tag usage was fine, but my if condition was off. It needed to be:
if (Model.Book.ReviewReference.EntityKey == null)
I was missing the EntityKey property.
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