Preventing repeated data into the gridview

Question

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.

Dennis Myers · Answer

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 Suresh · Answer

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 S · Answer

Vishnu  Please Post the BindData Method as well. Thanks Priyan

Vishnu Suresh · Answer

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=' '> Text=' '> ontextchanged=txtSlno_TextChanged Width=70px /> Text=' ' Width=70px> Text=' '> onkeyup=javascript:__doPostBack('UpdatePanel1''') ontextchanged=txtcode_TextChanged ReadOnly=false Width=70px />

Priyaranjan K S · Answer

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 Suresh · Answer

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 S · Answer

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 Suresh · Answer

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 S · Answer

Hi Vishnu You have put the code I gave inside a for loop . for (int i = 0; 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 Suresh · Answer

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 { 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 S · Answer

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 Suresh · Answer

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 S · Answer

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 Menoth · Answer

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 Suresh · Answer

@Priyaranjan I have tried the above code u gave. But its always displaying data repeated. for (int i = 0; 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 S · Answer

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 Menoth · Answer

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