How to use Distinct in LINQ?

C# Linq Distinct() method removes the duplicate elements from a sequence (list) and returns the distinct elements from a single data source. It comes under the Set operators’ category in LINQ query operators, and the method works the same way as the DISTINCT directive in Structured Query Language (SQL).

How to get Distinct values from LINQ in c#?

By Using LINQ we can read distinct values….Now write your code like below:

  1. public JsonResult getEmpCity()
  2. {
  3. using (CompanyDBEntities dc = new CompanyDBEntities())
  4. {
  5. var query = (from p in dc. Emp_Information.
  6. select p. City). Distinct(). ToList();
  7. return new JsonResult.
  8. {

Why distinct is not working in LINQ?

LINQ Distinct is not that smart when it comes to custom objects. All it does is look at your list and see that it has two different objects (it doesn’t care that they have the same values for the member fields). One workaround is to implement the IEquatable interface as shown here.

Does LINQ distinct use equals?

c# – Linq distinct doesn’t call Equals method – Stack Overflow. Stack Overflow for Teams – Start collaborating and sharing organizational knowledge.

How do I get distinct values in lambda expression?

“how to get distinct values from list in c# using lambda” Code Answer

  1. if (! IsPostBack) {
  2. GridView1. DataSource = GetProducts()
  3. . GroupBy(o => new { o. Make, o. Model })
  4. . Select(o => o. FirstOrDefault());
  5. GridView1. DataBind();
  6. }

How do I select distinct values in LINQ query?

  1. The Distinct() method is used to remove the duplicate values from the list and gives the unique values.
  2. The Distinct() function in LINQ can be applied by the properties.
  3. When you use reference type object, LINQ will treat the values as unique even the property values are same.

What is IEquatable in C#?

The IEquatable interface is used by generic collection objects such as Dictionary, List, and LinkedList when testing for equality in such methods as Contains , IndexOf , LastIndexOf , and Remove . It should be implemented for any object that might be stored in a generic collection.

How do I use distinct in SELECT?

DISTINCT keyword in SQL is used to fetch only unique records from a database table. It is usually used in conjunction with the SELECT statement. For the uninitiated, the SELECT statement is used to fetch desired records from the datatable. Distinct keyword removes all duplicate records and fetches only unique ones.

How do you use distinct in a SELECT statement?

The distinct keyword is used with select keyword in conjunction. It is helpful when we avoid duplicate values present in the specific columns/tables. The unique values are fetched when we use the distinct keyword. SELECT DISTINCT returns only distinct (different) values.