LINQ had provided attribute based XML mapping. So you can have your pure .NET class like the ‘clsCustomer’ class shown below and you can define the LINQ mapping in a XML file. LINQ engine can then read the mapping from a XML file and apply the same to your simple .NET classes.
public class clsCustomer
{
private int _intCustomerId;
private string _strCustomerName;
private string _strCustomerCode;
public int CustomerId
{
set
{
_intCustomerId = value;
}
get
{
return _intCustomerId;
}
}
public string CustomerName
{
set
{
_strCustomerName = value;
}
get
{
return _strCustomerName;
}
}
public string CustomerCode
{
set
{
_strCustomerCode = value;
}
get
{
return _strCustomerCode;
}
}}
We need to then create a simple XML file which defines the mapping with the class members.
<?xml version="1.0" encoding="utf-8"?>
<Database Name="TstServer" xmlns="http://schemas.microsoft.com/linqtosql/mapping/2007">
<Table Name="dbo.Customer" Member="WebAppMappingXML.clsCustomer">
<Type Name="WebAppMappingXML.clsCustomer">
<Column Name="CustomerId" Member="CustomerId" />
<Column Name="CustomerName" Member="CustomerName" />
<Column Name="CustomerCode" Member="CustomerCode" />
</Type>
</Table>
</Database>
To bind the XML mapping with the simple .NET class we need to first create the XMLMappingSource object as shown in the below code snippet.
XmlMappingSource xms = XmlMappingSource.FromUrl(physicalPath + "Mapping.xml");
We need to pass the XMLMappingSource object to the datacontext class shown in the below code snippet.
DataContext objContext = new DataContext(strConn, xms);
Finally we can get the table and loop through the entity objects.
var query = from customer in objContext.GetTable<clsCustomer>()
select customer;
foreach (var item in query)
{
Response.Write(item.CustomerCode + "<br>");
}
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