How to enumerate FormCollection in ASP.NET MVC? Wednesday, Aug 31 2011 

Here are 5 ways to do it specifically with a FormCollection object.

public ActionResult SomeActionMethod(FormCollection formCollection)
{
  foreach (var key in formCollection.AllKeys)
  {
    var value = formCollection[key];
  }

  foreach (var key in formCollection.Keys)
  {
    var value = formCollection[key.ToString()];
  }

  // Using the ValueProvider
  var valueProvider = formCollection.ToValueProvider();
  foreach (var key in valueProvider.Keys)
  {
    var value = valueProvider[key];
  }


foreach(var key in Request.Form.AllKeys)
{
   var value = Request.Form[key];
}
foreach(KeyValuePair<string, ValueProviderResult> kvp in form.ToValueProvider())
{
    string htmlControlName = kvp.Key;
    string htmlControlValue = kvp.Value.AttemptedValue;
}
}







Advertisements

C# Razor Syntax Quick Reference Tuesday, Aug 30 2011 

I gave a presentation to another team at Microsoft yesterday on ASP.NET MVC and the Razor view engine and someone asked if there was a reference for the Razor syntax.

It turns out, there is a pretty good guide about Razor available, but it’s focused on covering the basics of web programming using Razor and inline pages and not just the Razor syntax.

So I thought it might be handy to write up a a really concise quick reference about the Razor syntax.

Syntax/Sample Razor Web Forms Equivalent (or remarks)
Code Block
@{ 
  int x = 123; 
  string y = "because.";
}
<%
  int x = 123; 
  string y = "because."; 
%>
Expression (Html Encoded)
<span>@model.Message</span>
<span><%: model.Message %></span>
Expression (Unencoded)
<span>
@Html.Raw(model.Message)
</span>
<span><%= model.Message %></span>
Combining Text and markup
@foreach(var item in items) {
  <span>@item.Prop</span> 
}
<% foreach(var item in items) { %>
  <span><%: item.Prop %></span>
<% } %>
Mixing code and Plain text
@if (foo) {
  <text>Plain Text</text> 
}
<% if (foo) { %> 
  Plain Text 
<% } %>
Mixing code and plain text (alternate)
@if (foo) {
  @:Plain Text is @bar
}
Same as above
Email Addresses
Hi philha@example.com
Razor recognizes basic email format and is smart enough not to treat the @ as a code delimiter
Explicit Expression
<span>ISBN@(isbnNumber)</span>
In this case, we need to be explicit about the expression by using parentheses.
Escaping the @ sign
<span>In Razor, you use the 
@@foo to display the value 
of foo</span>
@@ renders a single @ in the response.
Server side Comment
@*
This is a server side 
multiline comment 
*@
<%--
This is a server side 
multiline comment
--%>
Calling generic method
@(MyClass.MyMethod<AType>())
Use parentheses to be explicit about what the expression is.
Creating a Razor Delegate
@{
  Func<dynamic, object> b = 
   @<strong>@item</strong>;
}
@b("Bold this")
Generates a Func<T, HelperResult> that you can call from within Razor. See this blog post for more details.
Mixing expressions and text
Hello @title. @name.
Hello <%: title %>. <%: name %>.

Notice in the last example that Razor is smart enough to know that the ending period is a literal text punctuation and not meant to indicate that it’s trying to call a method or property of the expression.

Let me know if there are other examples you think should be placed in this guide. I hope you find this helpful.