how to multiply the value in gridview in asp.net

selvi subramanian

how to multiply the value in gridview.
this is my design


	onrowdatabound="GridView1_RowDataBound"> onselectedindexchanged="DropDownList1_SelectedIndexChanged"> Choose 1 2 3 4 5 6 7 8 9 10 >

code is

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;

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

{

SqlConnection con = new SqlConnection("Data Source=VALUED-HO1E64NO\\SQLEXPRESS;Initial Catalog=Agri;User ID=sa;Password=watt");

REMO sel = new REMO();

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

LoadData();

}

sno();

sg();

}

private void sno()

{

string bill = sel.getmaxid("BillNo", "cement1");

txtbillno.Text = bill.ToString();

}

void LoadData()

{

SqlConnection con = new SqlConnection("Data Source=VALUED-HO1E64NO\\SQLEXPRESS;Initial Catalog=Agri;User ID=sa;Password=watt");

SqlDataAdapter cmd=new SqlDataAdapter("select * from demo",con);

DataSet ds=new DataSet();

cmd.Fill(ds);

GridView1.DataSource = ds.Tables[0];

GridView1.DataBind();

}

private void sg()

{

ListItem sll = new ListItem();

DropDownList3.Items.Add("Cement");

DropDownList3.Items.Add("Seed");

DropDownList3.Items.Add("Pesticide");

DropDownList3.Items.Add("Fetilizer");

DropDownList3.Items.Add(sll.ToString());

}

protected void txtbillno_TextChanged(object sender, EventArgs e)

{

// DataTable dt;

//dt="select

}

// private void prr()

//{

// int s = 0;

// DataSet ds=new DataSet();

// ListItem lim = new ListItem();

// //lim.Text = "Select";

// //lim.Value = "0";

// //DropDownList1.Items.Add(lim.ToString());

// ds = sel.GETDS("select DISTINCT name from demo");

// //DropDownList1.Items.Insert(0, new ListItem("--Select--", "0"));

// foreach (DataRow dr in ds.Tables[0].Rows)

// {

// // DropDownList1.Items.Clear();

// ListItem ss = new ListItem();

// lim.Text = dr["name"].ToString();

// lim.Value = Convert.ToString(s + 1);

// DropDownList1.Items.Add(lim.ToString());

// }

//}

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)

{

if (e.Row.RowType == DataControlRowType.DataRow)

{

con.Open();

var ddl = (DropDownList)e.Row.FindControl("ddlw");

//int CountryId = Convert.ToInt32(e.Row.Cells[0].Text);

SqlCommand cmd = new SqlCommand("select weight from demo" , con);

SqlDataAdapter da = new SqlDataAdapter(cmd);

DataSet ds = new DataSet();

da.Fill(ds);

con.Close();

ddl.DataSource = ds;

ddl.DataTextField = "weight";

//ddl.DataValueField = "StateID";

ddl.DataBind();

ddl.Items.Insert(0, new ListItem("--Select--", "0"));

float sllv = Convert.ToInt32((TextBox)GridView1.FindControl("pprice"));

float scv = Convert.ToInt32((DropDownList)GridView1.FindControl("DropDownList1"));

((TextBox)e.Row.FindControl("bfvata")).Text = Convert.ToString(sllv * scv);

}

protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)

{

}

i need to multiply the value in (requiredno* productprice)=beforevat

11 Replies

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

Suthish Nair13y ago
First of all Control Name is "pprce" not "pprice".

Secondly, you must a null check before converting any value.

So change you code...

TextBox txtpprce = (TextBox)e.Row.FindControl("pprce");
if(txtpprce != null)
{
DropDownList ddlDropDownList1 = (DropDownList)e.Row.FindControl("DropDownList1");
if(ddlDropDownList1 != null)
{
TextBox txtbfvata = (TextBox)e.Row.FindControl("bfvata");
if(txtbfvata != null)
{
txtbfvata.Text = Convert.ToString(Convert.ToInt32(txtpprce.Text) * Convert.ToInt32(ddlDropDownList1.SelectedItem.Text));
}
}
}
Jignesh Trivedi13y ago
is it same error?

can please check what is value of (TextBox)e.Row.FindControl("pprce")? when you getting error.
selvi subramanian13y ago
its present pls u check it .it throw the error
Jignesh Trivedi13y ago
hi,
This error means...
your text box is not present on the currently accessed row...
Please check your code whether this text box present or not...
selvi subramanian13y ago
stil it contain error as System.NullReferenceException: Object reference not set to an instance of an object. show like this float sllv = Convert.ToInt32(((TextBox)GridView1.FindControl("pprce")).Text); in this line it shows as red colour
Jignesh Trivedi13y ago
hi,
I am not able to find pprice control on your grid code. i think it pprce....
also this multification is row by row so code must....
float sllv = Convert.ToInt32(((TextBox)e.Row.FindControl("pprce")).Text);
float scv = Convert.ToInt32(((DropDownList)e.Row.FindControl("DropDownList1")).SelectValue);
hope this will help you.
selvi subramanian13y ago
its not working
Jignesh Trivedi13y ago
hi,

I think, problem you code is, you are trying to convert textbox / dropdown in to int. but actually you must convert textbox / dropdown value into int...

try...
below two line replace with your code.

float sllv = Convert.ToInt32(((TextBox)GridView1.FindControl("pprice")).Text);
float scv = Convert.ToInt32(((DropDownList)GridView1.FindControl("DropDownList1")).SelectValue);

hope this will help you
selvi subramanian13y ago
but it cum zero only
Jignesh Trivedi13y ago
hi,

your code looks good and also it must work fine..
are you facing any problem with this code?
Anurag Sarkar13y ago
You just need to take them into string and then you can multiply them.