checking values weather it is present in database or not??

hemant kumar

hiiii i have designed one window application i want to add feature in it it should check data in database before deleting updating n inserting records

2 Replies

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Satyapriya Nayak14y ago
Hi Hemant,

For windows app using Msaccess db

Try this...

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.OleDb;
namespace Insert_data_ifnot_exits_csharp
{
    public partial class Form1 : Form
    {
        string ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["dsn"];
        OleDbCommand com;
        OleDbDataAdapter oledbda;
        DataSet ds;
        string str;
        DataTable dt;

        public Form1()
        {
            InitializeComponent();
        }

        private void btn_insert_Click(object sender, EventArgs e)
        {
            namecheck();
        }

        public void namecheck()
        {
            OleDbConnection con = new OleDbConnection(ConnectionString);
            con.Open();
            str = "select count(*)from employee where ename='" + txtUserName.Text + "'";
            com = new OleDbCommand(str, con);
            int count = Convert.ToInt32(com.ExecuteScalar());
            con.Close();
            if (count > 0)
            {
                lblMessage.Text = "Sorry! you can't take this username";
            }
            else
            {
                lblMessage.Text = "You can take this username";
                con.Open();
                str = "insert into employee(ename) values('" + txtUserName.Text + "')";
                com = new OleDbCommand(str, con);
                com.ExecuteNonQuery();
                con.Close();

            }

        }



    }
}

Thanks
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Satyapriya Nayak14y ago
Hi Hemant,

Try this...

Table

create table employee (eid int primary key identity,ename varchar(50),eaddress varchar(50))

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="Insert_data_ifnot_exits._Default" %>

DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >

<head runat="server">

    <title>Untitled Pagetitle>

head>

<body>

    <form id="form1" runat="server">

    <div>



    div>

    <asp:Button ID="Button1" runat="server" Text="Availability of name from the database"

        BackColor="#FF99FF" Font-Bold="True" Width="329px"

        onclick="Button1_Click" /><br />

    <asp:Label ID="Labelcheck" Text="Ename" runat="server" BackColor="#FFFF99"

        Width="197px" ForeColor="#FF3300">asp:Label>

        <asp:TextBox ID="txtUserName" runat="server" Width="197px">asp:TextBox>



    <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server"

        ControlToValidate="txtUserName" ErrorMessage="*Name Required">asp:RequiredFieldValidator><br />





        <asp:Label ID="Label1" Text="Eaddress" runat="server" BackColor="#FFFF99"

        Width="197px" ForeColor="#FF3300">asp:Label>

        <asp:TextBox ID="txtUserAddress" runat="server" Width="197px">asp:TextBox>



    <asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server"

        ControlToValidate="txtUserAddress" ErrorMessage="*Address Required">asp:RequiredFieldValidator>



    <br />

    <asp:Label ID="lblMessage" runat="server" BackColor="#FF3300"

        ForeColor="Black">asp:Label>

    form>

body>

html>

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 Insert_data_ifnot_exits

{

    public partial class _Default : System.Web.UI.Page

    {

        string connStr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;

        SqlCommand com;

        string str = null;



        protected void Button1_Click(object sender, EventArgs e)

        {

            namecheck();

        }

        public void namecheck()

        {

            SqlConnection con = new SqlConnection(connStr);

            con.Open();

            str = "select count(*)from employee where ename='" + txtUserName.Text + "'";

            com = new SqlCommand(str, con);

            int count = Convert.ToInt32(com.ExecuteScalar());

            con.Close();

            if (count > 0)

            {

                lblMessage.Text = "Sorry! you can't take this username";

            }

            else

            {

                lblMessage.Text = "You can take this username";

                con.Open();

                str = "insert into employee(ename,eaddress) values('" + txtUserName.Text + "','" + txtUserAddress.Text + "')";

                com = new SqlCommand(str, con);

                com.ExecuteNonQuery();

                con.Close();

            }



        }

    }

}

Thanks
If this post helps you mark it as answer
0

checking values weather it is present in database or not??

Table