Preventing repeated data into the gridview

Vishnu Suresh

I have a .net program in which datas are to be inserted through gridview. If I am adding the same data twice then I need to show error message that data repeated. How can I do this. I have used one code but it shows error.

for (int i = 0; i < GridView1.Rows.Count; i++)

{

TextBox txtSlno = (TextBox)GridView1.Rows[i].Cells[1].FindControl("txtSlno");

if (txtSlno.Text != "" || txtSlno.Text != null)

{

if (txtSlno.Text == dt.Rows[i]["SlNo"].ToString())

{

Label1.Text = "already exist";

break;

}

else

{

Label1.Text = "";

}

It shows error there is no row at position zero.

17 Replies

Know the answer? Post it — somebody with the same question will find it here.

Dennis Myers9y ago
Protected void gv_GridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
if (e.Row.DataItemIndex != 0)
{
foreach(GridViewRow row in gv_GridView.Rows)
{
if (e.Row.Cells[5].Text == row.Cells[5].Text)
{
e.Row.Cells[5].ForeColor = (e.Row.Cells[5].Text != row.Cells[5].Text) ? Color.Green : Color.Red;
MessageBox3.ShowError("You have entered the same person twice, please delete the second entry.");
}
}
}

}
}
Vishnu Suresh11y ago
Hi Priyan,

This is my code

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.Net;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
using System.IO;
using System.Collections.Generic;
public partial class Default4 : System.Web.UI.Page
{
SqlConnection con = new SqlConnection("Data Source=xxxxx;Initial Catalog=xxxxx;User ID=xxxx;Password=xxxxx");
SqlCommand cmd = new SqlCommand();
SqlDataReader dr;
DataTable dt = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
BindData();
}
private void BindData()
{
string strQuery = "select * from dbtble2
SqlCommand cmd = new SqlCommand(strQuery);
GridView1.DataSource = GetData(cmd);
GridView1.DataBind();
}
private DataTable GetData(SqlCommand cmd)
{
DataTable dt = new DataTable();
SqlConnection con = new SqlConnection("Data Source=xxx;Initial Catalog=xxxx;User ID=xx;Password=xx");
SqlDataAdapter sda = new SqlDataAdapter();
cmd.CommandType = CommandType.Text;
cmd.Connection = con;
con.Open();
sda.SelectCommand = cmd;
sda.Fill(dt);
return dt;
}
protected void AddNewCustomer(object sender, EventArgs e)
{
Control control = null;
if (GridView1.FooterRow != null)
{
control = GridView1.FooterRow;
}
else
{
control = GridView1.Controls[0].Controls[0];
}
string SlNo = (control.FindControl("txtSlNo") as TextBox).Text;
string Code = (control.FindControl("txtcode") as TextBox).Text;
string details = (control.FindControl("txtdetails") as TextBox).Text;
using (SqlConnection con = new SqlConnection("Data Source=xxxxx;Initial Catalog=xxxx;User ID=xxxx;Password=xxxxx"))
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = con;
cmd.CommandType = CommandType.Text;
cmd.CommandText = "INSERT INTO [dbtble2] VALUES(@Code,@details,@SlNo)";
cmd.Parameters.AddWithValue("@SlNo", SlNo);
cmd.Parameters.AddWithValue("@Code", Code)
cmd.Parameters.AddWithValue("@details", details);
con.Open();
cmd.ExecuteNonQuery();
GridView1.DataBind();
BindData();
con.Close();
} }} } } }
protected void txtcode_TextChanged(object sender, EventArgs e)
{
Control control = null;
if (GridView1.FooterRow != null)
{
control = GridView1.FooterRow;
}
else
{
control = GridView1.Controls[0].Controls[0];
}
string CODE = (control.FindControl("txtcode") as TextBox).Text;
String str = "select top 10 * from dbtble1 where (CODE like + @search + '%')ORDER BY CODE ASC ;";
SqlCommand xp = new SqlCommand(str, con);
xp.Parameters.Add("@search", SqlDbType.VarChar).Value = (control.FindControl("txtcode") as TextBox).Text;
cmd.Parameters.AddWithValue("@CODE", CODE);
con.Open();
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = xp;
DataSet ds = new DataSet();
da.Fill(ds, "CODE");
GridView2.DataSource = ds;
GridView2.DataBind();
con.Close();
(control.FindControl("txtcode") as TextBox).Text = GridView2.Rows[0].Cells[1].Text.Replace(" ", " ");
(control.FindControl("txtdetails") as TextBox).Text = GridView2.Rows[0].Cells[5].Text.Replace(" ", " ");
}

}
Priyaranjan K S11y ago
Vishnu ,

Please Post the BindData Method as well.

Thanks,
Priyan
Vishnu Suresh11y ago
This is my gridview aspx code, I have placed textboxes inside the gridview and an add button in the gridview through which I am inserting the data.

onrowdatabound="GridView1_RowDataBound" onrowdeleting="GridView1_RowDeleting"
onrowediting="GridView1_RowEditing" onrowupdated="GridView1_RowUpdated"
onrowupdating="GridView1_RowUpdating"
onselectedindexchanged="GridView1_SelectedIndexChanged" ShowFooter="True"
onpageindexchanged="GridView1_PageIndexChanged"
onpageindexchanging="GridView1_PageIndexChanging"
onselectedindexchanging="GridView1_SelectedIndexChanging">

Text='<%#Container.DataItemIndex+1 %>'>

Text='<%# Eval("Slno")%>'>

ontextchanged="txtSlno_TextChanged" Width="70px" />

Text='<%# Eval("Code")%>' Width="70px">

Text='<%# Eval("Code")%>'>

onkeyup="javascript:__doPostBack('UpdatePanel1','')"
ontextchanged="txtcode_TextChanged" ReadOnly="false" Width="70px" />
Priyaranjan K S11y ago
From where are you entering this new data ? Is it directly into GVCell or is it a textbox placed in a Windows Form or any other input method ?

If you have an aspx mark up .Post that as well .
Vishnu Suresh11y ago
i am adding the data one by one. so if fist I add data eg slno 1 and code a1 then add slno 2 and code a2, then the gridview need to show error that the code u are entering is already exist.
Priyaranjan K S11y ago
Vishnu ,

In your case are you trying to update the Grid View table only if the 'new txtcode' is not already present in the table ?

Also How is this new record that has to be added to the Grid View obtained ? Is it entered by the user one at a time or a bulk of records are read from the back end and added to the Grid View which already has some data ?

Thanks,
Priyan
Vishnu Suresh11y ago
Hi Priyaranjan
I have removed that for loop. But here I am defining i in Rows
TextBox txtcode = (TextBox)GridView1.Rows[i].Cells[1].FindControl("txtcode");

so I added 1 in position of i and executed. But it will not displaying.
Priyaranjan K S11y ago
Hi Vishnu,

You have put the code I gave inside a for loop .

for (int i = 0; i < GridView1.Rows.Count; i++) // Comment this line
{
DataTable dataTable = (DataTable)GridView1.DataSource;
bool present = false;

You don't need that for loop . Try testing it now .

Thanks,
Priyan

If you found this useful Please mark this as answer
Vishnu Suresh11y ago
This is my code for adding the new data

protected void AddNew(object sender, EventArgs e)
{
Control control = null;
if (GridView1.FooterRow != null)
{
control = GridView1.FooterRow;
}
else
{
control = GridView1.Controls[0].Controls[0];
}
string SlNo = (control.FindControl("txtSlNo") as TextBox).Text;
string Code = (control.FindControl("txtcode") as TextBox).Text;
string details = (control.FindControl("txtdetails") as TextBox).Text;
string Qty = (control.FindControl("txtqty") as TextBox).Text;
string UPrice = (control.FindControl("txtuprice") as TextBox).Text;
using (SqlConnection con = new SqlConnection("Data Source=xxxxx;Initial Catalog=xxxxx;User ID=xx;Password=xxxxx"))
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = con;
cmd.CommandType = CommandType.Text;
cmd.CommandText = "INSERT INTO [qtable] VALUES(@Code,@details,@Qty,@UPrice)";
cmd.Parameters.AddWithValue("@SlNo", SlNo);
cmd.Parameters.AddWithValue("@Code", Code);
cmd.Parameters.AddWithValue("@details", details);
cmd.Parameters.AddWithValue("@Qty", Qty);
cmd.Parameters.AddWithValue("@UPrice", UPrice);
con.Open();
cmd.ExecuteNonQuery();
GridView1.DataBind();
BindData();
con.Close();
}
for (int i = 0; i < GridView1.Rows.Count; i++)
{
DataTable dataTable = (DataTable)GridView1.DataSource;
bool present = false;
foreach (DataRow dr in dataTable.Rows)
{
TextBox txtcode = (TextBox)GridView1.Rows[i].Cells[1].FindControl("txtcode");
if (dr["Code"].ToString() == txtcode.Text)
{
Label1.Text = "already exist";
present = true;
}
}
if (!present)
{
Label1.Text = "new code";
}
}
Priyaranjan K S11y ago
I tried the above code with my environment variables and it was not allowing duplicate data entry . Can you please post the updated code you are using now .

Thanks,
Priyan
Vishnu Suresh11y ago
Sir I executed this code also, but its not successfull, I couldnt find the error. Is there any other method is available for this.
Priyaranjan K S11y ago
Hi Vishnu ,

Please try out the below working code . Change the variables and grid view names as per your requirement .

DataTable dataTable = (DataTable)dataGridView1.DataSource;
bool present=false;
foreach (DataRow dr in dataTable.Rows)
{
if (dr["CustomerId"].ToString() == ID.Text)
{
Message.Text = "already exist";
present = true;
}
}
if (!present)
{
//Do the assignment here
}

Thanks,
Priyan

If you found this useful Please mark this as answer
Rajeesh Menoth11y ago
Hi,

Check these examples :

1) http://stackoverflow.com/questions/4415519/best-way-to-remove-duplicate-entries-from-a-data-table

2) http://www.aspsnippets.com/Articles/Remove-Delete-Duplicate-Rows-Records-from-DataTable-using-C-and-VBNet.aspx
Vishnu Suresh11y ago
@Priyaranjan I have tried the above code u gave. But its always displaying data repeated.

for (int i = 0; i < GridView1.Rows.Count; i++)
{
DataTable dataTable = (DataTable) GridView1.DataSource;
foreach(DataRow dr in dataTable.Rows)
{
TextBox txtslno = (TextBox)GridView1.Rows[i].Cells[1].FindControl("txtslno");
if (dr["slno"].ToString() == txtslno.Text)
{
Label1.Text = "already exist";
break;
}
else
{
Label1.Text = "";
}
}
Priyaranjan K S11y ago
Hi Vishnu,

Please try out the below code.

DataTable dataTable = (DataTable) GridView1.DataSource;
foreach(DataRow dr in dataTable.Rows)
{
if(dr["SlNo"].ToString() == txtSlno.Text )
{
Label1.Text = "already exist";
break;
}
else
{
Label1.Text = "";
}

}
Thanks,
Priyan

If you found this useful Please mark this as answer
Rajeesh Menoth11y ago
Hi,

Read this article :

http://www.codeproject.com/Articles/36697/Eliminate-Duplicate-Values-from-the-Grid-View