Ado.net with sql 2008

As i got you can use this string

string str = "select count(Field_Name) from Table-Name where Field_Name='"+ComboBox2.Selectedvalue+"'";

if this is not according per you requirement then please elaborate your query..............

sir, i don't want to  check entire table values . just i want to check the for pariticular field in the table data is already exist or not. please answer to this.


example:


i have 4 number of combobox just i want to check 2nd combobox only whether it is already exist or not.

Hello mem for it you can use count method like:


con.Open();
            string str = "select count(*) from pankaj where take='"+textBox2.Text+"'";
            SqlCommand com = new SqlCommand(str, con);
            int Num;
           Num= int.Parse( com.ExecuteScalar().ToString());

           if (Num > 0)
               MessageBox.Show("Data is already exist");
           else
           {
             //  Here you can perform your Operation
           }
            com.ExecuteNonQuery();
            con.Close();

Hi,
Before saving data into database you may check whether this value already exist in database or not
SqlCommand cmd = new SqlCommand("SELECT COUNT(*) FROM Employee where name ='jignesh' ", Connection);
int Records = int.Parse(cmd.ExecuteScalar().ToString());
if(Records >0)
{
 //Record already Exist
}
else
{
 // insert data...
}
hope this will help you.