Four popular properties of SqlDataReader object
4 important properties of SqlDataReader object in C#
In this article, we will discuss about
four important properties of SqlDataReader in ADO.NET C#.
We know SqlDataReader is very well
known ADO.NET class and it is used to read data in connected architecture. Let’s
see various properties of SqlDataReader one by one each of them.
FieldsCount to count number of columns in table.
Using this property we can count number
of column in fetched table. Here one table which has 3 columns is used.
using System;
using System.Collections;
using System.Globalization;
using System.Data.SqlClient;
using System.Data;
namespace Test1
{
class Program
{
static void Main(string[] args)
{
SqlConnection con = new SqlConnection();
con.ConnectionString="Data Source=SOURAV-PC\\SQL_INSTANCE2;Initial
Catalog=test;Integrated Security=True";
con.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = con;
cmd.CommandText = "select * from test";
SqlDataReader rd = cmd.ExecuteReader();
Console.WriteLine("Number of Colums :- " + rd.FieldCount);
Console.ReadLine();
}
}
}
Here is
sample output.
HasRows Property to check row if exists
or not.
Using this property we can check
whether any row is present or not in SqlDataReader. To check existence of any
row this property is useful. In below we can see sample code.
using System;
using System.Collections;
using System.Globalization;
using System.Data.SqlClient;
using System.Data;
namespace Test1
{
class Program
{
static void Main(string[] args)
{
SqlConnection con = new SqlConnection();
con.ConnectionString="Data Source=SOURAV-PC\\SQL_INSTANCE2;Initial
Catalog=test;Integrated Security=True";
con.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = con;
cmd.CommandText = "select * from test";
SqlDataReader rd = cmd.ExecuteReader();
Console.WriteLine("Rows present or not :- " + rd.HasRows);
Console.ReadLine();
}
}
}
Output is
here.
RecordsAffected
property to count number of record affected by query.
This
property works only with insert /update or deletes command and return number of
effected row(s). In below example we are inserting one record ,so the output is
1.
using System;
using System.Collections;
using System.Globalization;
using System.Data.SqlClient;
using System.Data;
namespace Test1
{
class Program
{
static void Main(string[] args)
{
SqlConnection con = new SqlConnection();
con.ConnectionString="Data Source=SOURAV-PC\\SQL_INSTANCE2;Initial
Catalog=test;Integrated Security=True";
con.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = con;
cmd.CommandText = "Insert into test values('test',20)";
SqlDataReader rd = cmd.ExecuteReader();
Console.WriteLine("Number of record effected: " + rd.RecordsAffected);
Console.ReadLine();
}
}
}
IsClosed
and IsOpen to check reader is open or close.
Using this
property we can check whether reader is open or close.
using System;
using System.Collections;
using System.Globalization;
using System.Data.SqlClient;
using System.Data;
namespace Test1
{
class Program
{
static void Main(string[] args)
{
SqlConnection con = new SqlConnection();
con.ConnectionString="Data Source=SOURAV-PC\\SQL_INSTANCE2;Initial
Catalog=test;Integrated Security=True";
con.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = con;
cmd.CommandText = "select * from test";
SqlDataReader rd = cmd.ExecuteReader();
Console.WriteLine("Status of Reader :- " + rd.IsClosed);
rd.Close();
Console.WriteLine("Status of Reader :- " + rd.IsClosed);
Console.ReadLine();
}
}
}
