Asp.net: How to avoid duplicate record insert on page refresh

In this tutorial I am going to explain how to avoid (prevent) duplicate record insert on page refresh in asp.net using C#, VB.net

In the previous article I have explained how to auto generate and display Serial number (rownumber) in asp.net gridview, how to check uncheck OR select/deselect checkboxesin asp.net gridview control using Jquery and how to Check and uncheck allrecords or showing rows using checkbox control in Gridview asp.net usingJavascript. 

Description:

After insert the record when we refresh the page, it will reinsert (duplicate) the record with same values. In this article I am going to explain the solution to insert duplicate entries.

Implementation:

HTML Markup:

  <fieldset style="width:30%">

        <legend>Avoid Duplicate record Insert on page refresh</legend>

        <table>

            <tr><td>Movie name :</td><td>

                <asp:TextBox ID="txtname" runat="server"></asp:TextBox></td></tr>

            <tr><td>Genre :</td><td>

                <asp:TextBox ID="txtgenre" runat="server"></asp:TextBox></td></tr>

            <tr><td>Budget :</td><td>

                <asp:TextBox ID="txtbudget" runat="server"></asp:TextBox></td></tr>

            <tr><td></td><td></td></tr>

            <tr><td></td><td>

                <asp:Button ID="btninsert" runat="server" Text="Save"/></td></tr>

            <tr><td colspan="2">

                <asp:Label ID="lblmessage" runat="server"></asp:Label></td></tr>

        </table>

    </fieldset>

Import/add the namespace

C# code:

using System.Data.SqlClient;

using System.Configuration;

using System.Data;

VB.net code:

Imports System.Data

Imports System.Configuration

Imports System.Data.SqlClient

Solution 1: Check record already exist or not

We have to check the duplicate record before inserting the record. If the record with same value exists, it will not insert the record into database.

Create Store Procedure to check the record exist

Create PROCEDURE Sp_InsertMovie

(

@name varchar(50),

@genre varchar(50),

@budget int,

@outputmessage varchar(1000) out

)

AS

BEGIN

            SET NOCOUNT ON;

if not Exists (Select * from Tb_Movie where Name=@name and Genre=@genre and Budget=@budget)

Begin

Insert into Tb_Movie (Name,Genre,Budget) values(@name,@genre,@budget)

set @outputmessage = 'Record Insert Successfully'

END

else

begin

set @outputmessage = 'Record Already Exist'

end

End

On button click right the below given code:

C# code:

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["con"].ToString());

protected void btninsert_Click(object sender, EventArgs e)

    {

        try

        {

            SqlCommand cmd = new SqlCommand("Sp_InsertMovie", con);

            cmd.CommandType = CommandType.StoredProcedure;

            con.Open();

            cmd.Parameters.AddWithValue("@name", txtname.Text);

            cmd.Parameters.AddWithValue("@genre", txtgenre.Text);

            cmd.Parameters.AddWithValue("@budget", txtbudget.Text);

            cmd.Parameters.Add("@outputmessage", SqlDbType.Char, 500);

            cmd.Parameters["@outputmessage"].Direction = ParameterDirection.Output;

            string message = (string)cmd.Parameters["@outputmessage"].Value;

            cmd.ExecuteNonQuery();

            con.Close();

            lblmessage.Text = message;

        }

        catch (Exception ex) { }

    }

VB.net Code:

  Dim con As New SqlConnection(ConfigurationManager.ConnectionStrings("con").ToString())

    Protected Sub btninsert_Click(sender As Object, e As EventArgs) Handles btninsert.Click

        Try

            Dim cmd As New SqlCommand("Sp_InsertMovie", con)

            cmd.CommandType = CommandType.StoredProcedure

            con.Open()

            cmd.Parameters.AddWithValue("@name", txtname.Text)

            cmd.Parameters.AddWithValue("@genre", txtgenre.Text)

            cmd.Parameters.AddWithValue("@budget", txtbudget.Text)

            cmd.Parameters.Add("@outputmessage", SqlDbType.[Char], 500)

            cmd.Parameters("@outputmessage").Direction = ParameterDirection.Output

            Dim message As String = DirectCast(cmd.Parameters("@outputmessage").Value, String)

            cmd.ExecuteNonQuery()

            con.Close()

            lblmessage.Text = message

        Catch ex As Exception

        End Try

    End Sub

Create store Procedure:

Create PROCEDURE Sp_InsertMovie

(

@name varchar(50),

@genre varchar(50),

@budget int

)

AS

BEGIN

            SET NOCOUNT ON;

Insert into Tb_Movie (Name,Genre,Budget) values(@name,@genre,@budget)

END

Solution 2: Redirect to same page

After insert the record redirect the user to same page.

C# code:

protected void btninsert_Click(object sender, EventArgs e)

    {

        try

        {

            SqlCommand cmd = new SqlCommand("Sp_InsertMovie", con);

            cmd.CommandType = CommandType.StoredProcedure;

            con.Open();

            cmd.Parameters.AddWithValue("@name", txtname.Text);

            cmd.Parameters.AddWithValue("@genre", txtgenre.Text);

            cmd.Parameters.AddWithValue("@budget", txtbudget.Text);          

            cmd.ExecuteNonQuery();

            con.Close();

            Response.Write("<script>alert('Record Insert Successfully');window.location='Default.aspx';</script>");

          //  Response.Redirect(Request.Url.AbsoluteUri);

        }

        catch (Exception ex) { }

    }

Vb.net code:

Dim con As New SqlConnection(ConfigurationManager.ConnectionStrings("con").ToString())

    Protected Sub btninsert_Click(sender As Object, e As EventArgs) Handles btninsert.Click

      Try

            Dim cmd As New SqlCommand("Sp_InsertMovie", con)

            cmd.CommandType = CommandType.StoredProcedure

            con.Open()

            cmd.Parameters.AddWithValue("@name", txtname.Text)

            cmd.Parameters.AddWithValue("@genre", txtgenre.Text)

            cmd.Parameters.AddWithValue("@budget", txtbudget.Text)

            cmd.ExecuteNonQuery()

            con.Close()

            '  Response.Redirect(Request.Url.AbsoluteUri);

            Response.Write("<script>alert('Record Insert Successfully');window.location='Default.aspx';</script>")

        Catch ex As Exception

        End Try

    End Sub

Solution 3: Redirect to another page

After insert the record redirect the user to another (success) page.

C# code:

protected void btninsert_Click(object sender, EventArgs e)

    {

        try

        {

            SqlCommand cmd = new SqlCommand("Sp_InsertMovie", con);

            cmd.CommandType = CommandType.StoredProcedure;

            con.Open();

            cmd.Parameters.AddWithValue("@name", txtname.Text);

            cmd.Parameters.AddWithValue("@genre", txtgenre.Text);

            cmd.Parameters.AddWithValue("@budget", txtbudget.Text);          

            cmd.ExecuteNonQuery();

            con.Close();

            Response.Write("<script>alert('Record Insert Successfully');window.location='frmsuccess.aspx';</script>");

        }

        catch (Exception ex) { }

    }

Vb.net code:

Protected Sub btninsert_Click(sender As Object, e As EventArgs) Handles btninsert.Click

      Try

            Dim cmd As New SqlCommand("Sp_InsertMovie", con)

            cmd.CommandType = CommandType.StoredProcedure

            con.Open()

            cmd.Parameters.AddWithValue("@name", txtname.Text)

            cmd.Parameters.AddWithValue("@genre", txtgenre.Text)

            cmd.Parameters.AddWithValue("@budget", txtbudget.Text)

            cmd.ExecuteNonQuery()

            con.Close()

            Response.Write("<script>alert('Record Insert Successfully');window.location='frmsuccess.aspx';</script>")

        Catch ex As Exception

        End Try

    End Sub