How to write linq query for DataTable in c#?

How to write linq query for DataTable in c#?

To query datatable using linq we call the AsEnumerable() method of the DataTable. Calling this method on the DataTable returns an object which implements the IEnumerable interface. Now we can perform LINQ queries on this object. Add a reference to the System.

Can we use LINQ to query against a DataTable?

Can we use linq to query against a DataTable? Explanation: We cannot use query against the DataTable’s Rows collection, since DataRowCollection doesn’t implement IEnumerable. We need to use the AsEnumerable() extension for DataTable.

What is the use of AsEnumerable in C#?

AsEnumerable() in C# To cast a specific type to its IEnumerable equivalent, use the AsEnumerable() method. It is an extension method. int[] arr = new int[5]; arr[0] = 10; arr[1] = 20; arr[2] = 30; arr[3] = 40; arr[4] = 50; Now, get the IEnumerable equivalent.

How return DataTable from LINQ?

1. public DataTable LINQResultToDataTable(IEnumerable Linqlist)
2. {
3. DataTable dt = new DataTable();
4. PropertyInfo[] columns = null;
5. if (Linqlist == null) return dt;
6. foreach (T Record in Linqlist)
7. {
8. if (columns == null)

Which method creates a DataTable from an existing one and includes the data?

ADO.NET enables us to create DataTable objects and add them to an existing DataSet. We can set constraint information for a DataTable by using the PrimaryKey and Unique properties of DataColumn objects, which are added to the Columns collection of the DataTable.

What is DataTable AsEnumerable?

The enumerable object returned by the AsEnumerable method is permanently bound to the DataTable that produced it. Multiple calls to the AsEnumerable method will return multiple, independent queryable objects that are all bound to the source DataTable.

What is the difference between AsEnumerable and AsQueryable?

The major difference is that IEnumerable will enumerate all elements, while IQueryable will enumerate elements based on query only.

How do you add reference system data DataSetExtensions?

How to add a reference to System. Data. DataSetExtensions to a Web Site ascx. cs file?

1. Find the assembly path.
2. Open a Visual Studio Command Prompt and run sn.exe -T “full\path. dll”
3. Add the following to the web. config based on the Public key token.

How can I get distinct values of a column in a DataTable using LINQ?

LINQ: Read Distinct Record from Data Table

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). ToList();
7. return new JsonResult.
8. {

What is the difference between DataTable and DataSet in C#?

A DataTable is an in-memory representation of a single database table. You can think of it as having columns and rows in the same way. A dataset is an in-memory representation of a database-like structure. It can have one or more DataTables and define relations between them, key or any fields etc.