How do i counter check data from the database using c#in Asp.net

Question

Hi Team how do i counter check the data which am entering through the textbox with the data in the current database. for instance if i have store code 001 in the database then i try entering the same code001 using c# in asp.net it should give me an error like this the code already exist regard George

Satyapriya Nayak · Answer

Hi George Try this... Table Create table product(code varchar(50)) Untitled Page BackColor=#FF99FF Font-Bold=True Width=329px onclick=btn_code_Click /> Width=197px ForeColor=#FF3300> ControlToValidate=txtCode ErrorMessage=*Code Required> ForeColor=Black> using System; using System.Collections; using System.Configuration; using System.Data; using System.Linq; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.HtmlControls; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Xml.Linq; using System.Data.SqlClient; namespace Counter_check_data { public partial class _Default : System.Web.UI.Page { string connStr = ConfigurationManager.ConnectionStrings[ConnectionString].ConnectionString; SqlCommand com; string str = null; protected void btn_code_Click(object sender EventArgs e) { Codecheck(); } public void Codecheck() { SqlConnection con = new SqlConnection(connStr); con.Open(); str = select count(*)from product where code=' + txtCode.Text + '; com = new SqlCommand(str con); int count = Convert.ToInt32(com.ExecuteScalar()); if (count > 0) { lblMessage.Text = Sorry! you can't take this code; } else { lblMessage.Text = You can take this code; } } } } Thanks If this post helps you mark it as answer

Senthilkumar · Answer

Hi George If you want to do this explicitly then you can use the select statement with passed value SELECT * FROM Products WHERE code=001 If you use the stored procedure then IF EXISTS(SELECT * FROM Products WHERE Code=1) BEGIN SELECT 1 END ELSE BEGIN SELECT 0 END I suggest you to use the auto increment value if you want to do serial number Code INT IDENTITY(11) Hope this will help you.