Step 01 : mapping linq collection class with sql dataTabel
i.) import following namespace
using System.Data.Linq;
using System.Data.Linq.Mapping;
ex :- [Table(Name = "D01_Invoice")] //data table Name
public class Invoice
{
private int _invoiceID;
[Column(IsPrimaryKey = true, Storage = "_invoiceID", Name = "D01_id")] //data mapping column Name
public int InvoiceID
{
get
{ return this._invoiceID; }
set { this._invoiceID = value; }
}
private string _invoiceNumber;
[Column(Storage = "_invoiceNumber", Name = "D01_InvoiceNumber", DbType = "numeric(18, 0)")]
public string InvoiceNumber
{
get
{
return this._invoiceNumber;
}
set
{
this._invoiceNumber = value;
}
}
}
step 2:
Create "DataContex" object . so that u have to give connection string or file store path
//string ConnSQL = ConfigurationManager.ConnectionStrings["ConnSQL"].ToString();
// SqlConnection sqlConnection = new SqlConnection(ConnSQL);
//sqlConnection.Open();
DataContext dataContex = new DataContext(sqlConnection);
step 3:
call linq query
IEnumerable invoice = dataContex.GetTable(); //it can be list
those are the basic step to mapping data table and getting data table using linq
step 4 :
if u need select data from linq data collection use following way
select query
IEnumerable empQuery =
from emp in Invoice
select emp;
filter Query
IEnumerable empQuery =
from emp in employees
where emp.Department == "IT Department" &&
emp.City == "Redmond"
select emp;
Order Query
IEnumerable empQuery =
from emp in employees
orderby emp.Department
select emp;
Sample code for Group
Sample of C# Code
Sample Code for Join
IEnumerable invoice = dataContex.GetTable();
IEnumerable invoiceDetails = dataContex.GetTable();
var invo = from inv in invoice
join details in invoiceDetails on inv.InvoiceNumber equals details.InvoiceNumberDetails into invDetails
select new { id= inv.InvoiceID,
invoiceNum = inv.InvoiceNumber,
invoiceDetails = invDetails};
foreach (var inv in invo)
{
Console.WriteLine(inv.invoiceNum);
foreach (var indetails in inv.invoiceDetails)
{
Console.WriteLine(indetails.InvoiceNumberDetails + indetails.ItemCode);
}
}
