Can Distinct be expressed using so-called embedded query rather than a method call

given the following code:

string[]  colors = {"red","green","blue","red","green","blue"};
var distinctColors = (f开发者_如何转开发rom c in colors select c).Distinct();
distinctColors.Dump();

Is it possible to fold the call .Distinct() into the embedded query syntax?

something like int T-SQL

select distinct color from TableofColors

C#'s query expression syntax doesn't include "distinct". VB's does, however - for example, from the MSDN docs for VB's Distinct clause:

// VB
Dim customerOrders = From cust In customers, ord In orders _
                     Where cust.CustomerID = ord.CustomerID _
                     Select cust.CompanyName, ord.OrderDate _
                     Distinct

The C# equivalent would have to explicitly call Distinct() in dot notation.

However, your example can still be simplified:

string[]  colors = {"red","green","blue","red","green","blue"};
var distinctColors = colors.Distinct();
distinctColors.Dump();

Don't think you have to use query expressions to use LINQ :)

There's no distinct embedded query syntax in C# as far as I'm aware. This is as close as it gets:

var distinctColors = (from color in colors
                      select color).Distinct()

Query comprehension syntax does not support the Distinct method.

In your case, you could simply write colors.Distinct(); you're not doing anything with the query expression.

You can try this

var dis = from c in colors
   group c by c;

foreach (var cVal in dis)
   {
      string s = cVal.Key;
   }