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

Question

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

Satyapriya Nayak · Answer

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 If this post helps you mark it as answer

Satyapriya Nayak · Answer

Hi Hemant, Try this... Normal 0 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 Page title > 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

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

Answers (2)