Creating and using a Class File in C#

I will show you the steps to create and use a class file in .NET (C#)

Step 1:

Right Click Project >> Select Add New Item >> Class

Step 2:

Create two functions in your class file.

public DataTable ExecuteSlelectQry(string Query)

{

SqlConnection oSqlCon = new SqlConnection(FunGenerateConnectionString(StrCompanyCOde));

DataTable oSqldt = new DataTable();

try

{

using (SqlDataAdapter oSqlda = new SqlDataAdapter(Query, oSqlCon))

{

if (oSqlCon.State == ConnectionState.Closed)

{

oSqlCon.Open();

}

oSqlda.SelectCommand.CommandTimeout = 0;

oSqlda.Fill(oSqldt);

oSqlCon.Close();

}

}

catch (Exception ex)

{

if (oSqlCon.State == ConnectionState.Open)

{

oSqlCon.Close();

}

}

oSqldt.TableName = "RETURN";

return oSqldt;

}

public bool ExecuteNonSelectQry(string Query)

{

SqlConnection oSqlCon = new SqlConnection(FunGenerateConnectionString(StrCompanyCOde));

try

{

using (SqlCommand cmd = new SqlCommand(Query, oSqlCon))

{

if (oSqlCon.State == ConnectionState.Closed)

{

oSqlCon.Open();

}

cmd.CommandTimeout = 0;

cmd.ExecuteNonQuery();

oSqlCon.Close();

}

return true;

}

catch (Exception ex)

{

if (oSqlCon.State == ConnectionState.Open)

{

oSqlCon.Close();

}

return false;

}

}

Step 3:

Create the object of the class on your code behind page

Class oClsClass = new Class();

Step 4:

Access the class functions 1

Datatable oDT = new datatable
oDT = oClsClass.ExecuteSlelectQry("Select * from Employees")

Access the class functions 2

oClsClass.ExecuteNonSelectQry("Insert into Employees(EmpName) values("Abcd")"